Adding upstream version 0.37.0.upstream/0.37.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 2050 insertions, 0 deletions

diff --git a/player/javascript.c b/player/javascript.c
new file mode 100644
index 0000000..5be7277
--- /dev/null
+++ b/player/javascript.c
@@ -0,0 +1,1262 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <math.h>
+#include <stdint.h>
+
+#include <mujs.h>
+
+#include "osdep/io.h"
+#include "mpv_talloc.h"
+#include "common/common.h"
+#include "options/m_property.h"
+#include "common/msg.h"
+#include "common/msg_control.h"
+#include "common/stats.h"
+#include "options/m_option.h"
+#include "input/input.h"
+#include "options/path.h"
+#include "misc/bstr.h"
+#include "osdep/timer.h"
+#include "osdep/threads.h"
+#include "stream/stream.h"
+#include "sub/osd.h"
+#include "core.h"
+#include "command.h"
+#include "client.h"
+#include "libmpv/client.h"
+
+// List of builtin modules and their contents as strings.
+// All these are generated from player/javascript/*.js
+static const char *const builtin_files[][3] = {
+    {"@/defaults.js",
+#   include "player/javascript/defaults.js.inc"
+    },
+    {0}
+};
+
+// Represents a loaded script. Each has its own js state.
+struct script_ctx {
+    const char *filename;
+    const char *path; // NULL if single file
+    struct mpv_handle *client;
+    struct MPContext *mpctx;
+    struct mp_log *log;
+    char *last_error_str;
+    size_t js_malloc_size;
+    struct stats_ctx *stats;
+};
+
+static struct script_ctx *jctx(js_State *J)
+{
+    return (struct script_ctx *)js_getcontext(J);
+}
+
+static mpv_handle *jclient(js_State *J)
+{
+    return jctx(J)->client;
+}
+
+static void pushnode(js_State *J, mpv_node *node);
+static void makenode(void *ta_ctx, mpv_node *dst, js_State *J, int idx);
+static int jsL_checkint(js_State *J, int idx);
+static uint64_t jsL_checkuint64(js_State *J, int idx);
+
+/**********************************************************************
+ *  conventions, MuJS notes and vm errors
+ *********************************************************************/
+// - push_foo functions are called from C and push a value to the vm stack.
+//
+// - JavaScript C functions are code which the vm can call as a js function.
+//   By convention, script_bar and script__baz are js C functions. The former
+//   is exposed to end users as bar, and _baz is for internal use.
+//
+// - js C functions get a fresh vm stack with their arguments, and may
+//   manipulate their stack as they see fit. On exit, the vm considers the
+//   top value of their stack as their return value, and GC the rest.
+//
+// - js C function's stack[0] is "this", and the rest (1, 2, ...) are the args.
+//   On entry the stack has at least the number of args defined for the func,
+//   padded with undefined if called with less, or bigger if called with more.
+//
+// - Almost all vm APIs (js_*) may throw an error - a longjmp to the last
+//   recovery/catch point, which could skip releasing resources. This includes
+//   js_try itself(!), except at the outer-most [1] js_try which is always
+//   entering the try part (and the catch part if the try part throws).
+//   The assumption should be that anything can throw and needs careful setup.
+//   One such automated setup is the autofree mechanism. Details later.
+//
+// - Unless named s_foo, all the functions at this file (inc. init) which
+//   touch the vm may throw, but either cleanup resources regardless (mostly
+//   autofree) or leave allocated resources on caller-provided talloc context
+//   which the caller should release, typically with autofree (e.g. makenode).
+//
+// - Functions named s_foo (safe foo) never throw if called at the outer-most
+//   try-levels, or, inside JS C functions - never throw after allocating.
+//   If they didn't throw then they return 0 on success, 1 on js-errors.
+//
+// [1] In practice the N outer-most (nested) tries are guaranteed to enter the
+//     try/carch code, where N is the mujs try-stack size (64 with mujs 1.1.3).
+//     But because we can't track try-level at (called-back) JS C functions,
+//     it's only guaranteed when we know we're near the outer-most try level.
+
+/**********************************************************************
+ *  mpv scripting API error handling
+ *********************************************************************/
+// - Errors may be thrown on some cases - the reason is at the exception.
+//
+// - Some APIs also set last error which can be fetched with mp.last_error(),
+//   where empty string (false-y) is success, or an error string otherwise.
+//
+// - The rest of the APIs are guaranteed to return undefined on error or a
+//   true-thy value on success and may or may not set last error.
+//
+// - push_success, push_failure, push_status and pushed_error set last error.
+
+// iserr as true indicates an error, and if so, str may indicate a reason.
+// Internally ctx->last_error_str is never NULL, and empty indicates success.
+static void set_last_error(struct script_ctx *ctx, bool iserr, const char *str)
+{
+    ctx->last_error_str[0] = 0;
+    if (!iserr)
+        return;
+    if (!str || !str[0])
+        str = "Error";
+    ctx->last_error_str = talloc_strdup_append(ctx->last_error_str, str);
+}
+
+// For use only by wrappers at defaults.js.
+// arg: error string. Use empty string to indicate success.
+static void script__set_last_error(js_State *J)
+{
+    const char *e = js_tostring(J, 1);
+    set_last_error(jctx(J), e[0], e);
+}
+
+// mp.last_error() . args: none. return the last error without modifying it.
+static void script_last_error(js_State *J)
+{
+    js_pushstring(J, jctx(J)->last_error_str);
+}
+
+// Generic success for APIs which don't return an actual value.
+static void push_success(js_State *J)
+{
+    set_last_error(jctx(J), 0, NULL);
+    js_pushboolean(J, true);
+}
+
+// Doesn't (intentionally) throw. Just sets last_error and pushes undefined
+static void push_failure(js_State *J, const char *str)
+{
+    set_last_error(jctx(J), 1, str);
+    js_pushundefined(J);
+}
+
+// Most of the scripting APIs are either sending some values and getting status
+// code in return, or requesting some value while providing a default in case an
+// error happened. These simplify the C code for that and always set last_error.
+
+static void push_status(js_State *J, int err)
+{
+    if (err >= 0) {
+        push_success(J);
+    } else {
+        push_failure(J, mpv_error_string(err));
+    }
+}
+
+ // If err is success then return 0, else push the item at def and return 1
+static bool pushed_error(js_State *J, int err, int def)
+{
+    bool iserr = err < 0;
+    set_last_error(jctx(J), iserr, iserr ? mpv_error_string(err) : NULL);
+    if (!iserr)
+        return false;
+
+    js_copy(J, def);
+    return true;
+}
+
+/**********************************************************************
+ *  Autofree - care-free resource deallocation on vm errors, and otherwise
+ *********************************************************************/
+// - Autofree (af) functions are called with a talloc context argument which is
+//   freed after the function exits - either normally or because it threw an
+//   error, on the latter case it then re-throws the error after the cleanup.
+//
+//   Autofree js C functions should have an additional void* talloc arg and
+//   inserted into the vm using af_newcfunction, but otherwise used normally.
+//
+//  To wrap an autofree function af_TARGET in C:
+//  1. Create a wrapper s_TARGET which does this:
+//      if (js_try(J))
+//          return 1;
+//      *af = talloc_new(NULL);
+//      af_TARGET(J, ..., *af);
+//      js_endtry(J);
+//      return 0;
+//  2. Use s_TARGET like so (frees if allocated, throws if {s,af}_TARGET threw):
+//       void *af = NULL;
+//       int r = s_TARGET(J, ..., &af);  // use J, af where the callee expects.
+//       talloc_free(af);
+//       if (r)
+//           js_throw(J);
+//
+//  The reason that the allocation happens inside try/catch is that js_try
+//  itself can throw (if it runs out of try-stack) and therefore the code
+//  inside the try part is not reached - but neither is the catch part(!),
+//  and instead it throws to the next outer catch - but before we've allocated
+//  anything, hence no leaks on such case. If js_try did get entered, then the
+//  allocation happened, and then if af_TARGET threw then s_TARGET will catch
+//  it (and return 1) and we'll free if afterwards.
+
+// add_af_file, add_af_dir, add_af_mpv_alloc take a valid FILE*/DIR*/char* value
+// respectively, and fclose/closedir/mpv_free it when the parent is freed.
+
+static void destruct_af_file(void *p)
+{
+    fclose(*(FILE**)p);
+}
+
+static void add_af_file(void *parent, FILE *f)
+{
+    FILE **pf = talloc(parent, FILE*);
+    *pf = f;
+    talloc_set_destructor(pf, destruct_af_file);
+}
+
+static void destruct_af_dir(void *p)
+{
+    closedir(*(DIR**)p);
+}
+
+static void add_af_dir(void *parent, DIR *d)
+{
+    DIR **pd = talloc(parent, DIR*);
+    *pd = d;
+    talloc_set_destructor(pd, destruct_af_dir);
+}
+
+static void destruct_af_mpv_alloc(void *p)
+{
+    mpv_free(*(char**)p);
+}
+
+static void add_af_mpv_alloc(void *parent, char *ma)
+{
+    char **p = talloc(parent, char*);
+    *p = ma;
+    talloc_set_destructor(p, destruct_af_mpv_alloc);
+}
+
+static void destruct_af_mpv_node(void *p)
+{
+    mpv_free_node_contents((mpv_node*)p);  // does nothing for MPV_FORMAT_NONE
+}
+
+// returns a new zeroed allocated struct mpv_node, and free it and its content
+// when the parent is freed.
+static mpv_node *new_af_mpv_node(void *parent)
+{
+    mpv_node *p = talloc_zero(parent, mpv_node);  // .format == MPV_FORMAT_NONE
+    talloc_set_destructor(p, destruct_af_mpv_node);
+    return p;
+}
+
+// Prototype for autofree functions which can be called from inside the vm.
+typedef void (*af_CFunction)(js_State*, void*);
+
+// safely run autofree js c function directly
+static int s_run_af_jsc(js_State *J, af_CFunction fn, void **af)
+{
+    if (js_try(J))
+        return 1;
+    *af = talloc_new(NULL);
+    fn(J, *af);
+    js_endtry(J);
+    return 0;
+}
+
+// The trampoline function through which all autofree functions are called from
+// inside the vm. Obtains the target function address and autofree-call it.
+static void script__autofree(js_State *J)
+{
+    // The target function is at the "af_" property of this function instance.
+    js_currentfunction(J);
+    js_getproperty(J, -1, "af_");
+    af_CFunction fn = (af_CFunction)js_touserdata(J, -1, "af_fn");
+    js_pop(J, 2);
+
+    void *af = NULL;
+    int r = s_run_af_jsc(J, fn, &af);
+    talloc_free(af);
+    if (r)
+        js_throw(J);
+}
+
+// Identical to js_newcfunction, but the function is inserted with an autofree
+// wrapper, and its prototype should have the additional af argument.
+static void af_newcfunction(js_State *J, af_CFunction fn, const char *name,
+                            int length)
+{
+    js_newcfunction(J, script__autofree, name, length);
+    js_pushnull(J);  // a prototype for the userdata object
+    js_newuserdata(J, "af_fn", fn, NULL);  // uses a "af_fn" verification tag
+    js_defproperty(J, -2, "af_", JS_READONLY | JS_DONTENUM | JS_DONTCONF);
+}
+
+/**********************************************************************
+ *  Initialization and file loading
+ *********************************************************************/
+
+static const char *get_builtin_file(const char *name)
+{
+    for (int n = 0; builtin_files[n][0]; n++) {
+        if (strcmp(builtin_files[n][0], name) == 0)
+            return builtin_files[n][1];
+    }
+    return NULL;
+}
+
+// Push up to limit bytes of file fname: from builtin_files, else from the OS.
+static void af_push_file(js_State *J, const char *fname, int limit, void *af)
+{
+    char *filename = mp_get_user_path(af, jctx(J)->mpctx->global, fname);
+    MP_VERBOSE(jctx(J), "Reading file '%s'\n", filename);
+    if (limit < 0)
+        limit = INT_MAX - 1;
+
+    const char *builtin = get_builtin_file(filename);
+    if (builtin) {
+        js_pushlstring(J, builtin, MPMIN(limit, strlen(builtin)));
+        return;
+    }
+
+    FILE *f = fopen(filename, "rb");
+    if (!f)
+        js_error(J, "cannot open file: '%s'", filename);
+    add_af_file(af, f);
+
+    int len = MPMIN(limit, 32 * 1024);  // initial allocation, size*2 strategy
+    int got = 0;
+    char *s = NULL;
+    while ((s = talloc_realloc(af, s, char, len))) {
+        int want = len - got;
+        int r = fread(s + got, 1, want, f);
+
+        if (feof(f) || (len == limit && r == want)) {
+            js_pushlstring(J, s, got + r);
+            return;
+        }
+        if (r != want)
+            js_error(J, "cannot read data from file: '%s'", filename);
+
+        got = got + r;
+        len = MPMIN(limit, len * 2);
+    }
+
+    js_error(J, "cannot allocate %d bytes for file: '%s'", len, filename);
+}
+
+// Safely run af_push_file.
+static int s_push_file(js_State *J, const char *fname, int limit, void **af)
+{
+    if (js_try(J))
+        return 1;
+    *af = talloc_new(NULL);
+    af_push_file(J, fname, limit, *af);
+    js_endtry(J);
+    return 0;
+}
+
+// Called directly, push up to limit bytes of file fname (from builtin/os).
+static void push_file_content(js_State *J, const char *fname, int limit)
+{
+    void *af = NULL;
+    int r = s_push_file(J, fname, limit, &af);
+    talloc_free(af);
+    if (r)
+        js_throw(J);
+}
+
+// utils.read_file(..). args: fname [,max]. returns [up to max] bytes as string.
+static void script_read_file(js_State *J)
+{
+    int limit = js_isundefined(J, 2) ? -1 : jsL_checkint(J, 2);
+    push_file_content(J, js_tostring(J, 1), limit);
+}
+
+// Runs a file with the caller's this, leaves the stack as is.
+static void run_file(js_State *J, const char *fname)
+{
+    MP_VERBOSE(jctx(J), "Loading file %s\n", fname);
+    push_file_content(J, fname, -1);
+    js_loadstring(J, fname, js_tostring(J, -1));
+    js_copy(J, 0);  // use the caller's this
+    js_call(J, 0);
+    js_pop(J, 2);  // result, file content
+}
+
+// The spec defines .name and .message for Error objects. Most engines also set
+// a very convenient .stack = name + message + trace, but MuJS instead sets
+// .stackTrace = trace only. Normalize by adding such .stack if required.
+// Run this before anything such that we can get traces on any following errors.
+static const char *norm_err_proto_js = "\
+    if (Error().stackTrace && !Error().stack) {\
+        Object.defineProperty(Error.prototype, 'stack', {\
+            get: function() {\
+                return this.name + ': ' + this.message + this.stackTrace;\
+            }\
+        });\
+    }\
+";
+
+static void add_functions(js_State*, struct script_ctx*);
+
+// args: none. called as script, setup and run the main script
+static void script__run_script(js_State *J)
+{
+    js_loadstring(J, "@/norm_err.js", norm_err_proto_js);
+    js_copy(J, 0);
+    js_pcall(J, 0);
+
+    struct script_ctx *ctx = jctx(J);
+    add_functions(J, ctx);
+    run_file(J, "@/defaults.js");
+    run_file(J, ctx->filename);  // the main file to run
+
+    if (!js_hasproperty(J, 0, "mp_event_loop") || !js_iscallable(J, -1))
+        js_error(J, "no event loop function");
+    js_copy(J, 0);
+    js_call(J, 0); // mp_event_loop
+}
+
+// Safely set last error from stack top: stack trace or toString or generic.
+// May leave items on stack - the caller should detect and pop if it cares.
+static void s_top_to_last_error(struct script_ctx *ctx, js_State *J)
+{
+    set_last_error(ctx, 1, "unknown error");
+    if (js_try(J))
+        return;
+    if (js_isobject(J, -1))
+        js_hasproperty(J, -1, "stack");  // fetches it if exists
+    set_last_error(ctx, 1, js_tostring(J, -1));
+    js_endtry(J);
+}
+
+// MuJS can report warnings through this.
+static void report_handler(js_State *J, const char *msg)
+{
+    MP_WARN(jctx(J), "[JS] %s\n", msg);
+}
+
+// Safely setup the js vm for calling run_script.
+static int s_init_js(js_State *J, struct script_ctx *ctx)
+{
+    if (js_try(J))
+        return 1;
+    js_setcontext(J, ctx);
+    js_setreport(J, report_handler);
+    js_newcfunction(J, script__run_script, "run_script", 0);
+    js_pushglobal(J);  // 'this' for script__run_script
+    js_endtry(J);
+    return 0;
+}
+
+static void *mp_js_alloc(void *actx, void *ptr, int size_)
+{
+    if (size_ < 0)
+        return NULL;
+
+    struct script_ctx* ctx = actx;
+    size_t size = size_, osize = 0;
+    if (ptr)  // free/realloc
+        osize = ta_get_size(ptr);
+
+    void *ret = talloc_realloc_size(actx, ptr, size);
+
+    if (!size || ret) {  // free / successful realloc/malloc
+        ctx->js_malloc_size = ctx->js_malloc_size - osize + size;
+        stats_size_value(ctx->stats, "mem", ctx->js_malloc_size);
+    }
+    return ret;
+}
+
+/**********************************************************************
+ *  Initialization - booting the script
+ *********************************************************************/
+// s_load_javascript: (entry point) creates the js vm, runs the script, returns
+//                    on script exit or uncaught js errors. Never throws.
+// script__run_script: - loads the built in functions and vars into the vm
+//                     - runs the default file[s] and the main script file
+//                     - calls mp_event_loop, returns on script-exit or throws.
+//
+// Note: init functions don't need autofree. They can use ctx as a talloc
+// context and free normally. If they throw - ctx is freed right afterwards.
+static int s_load_javascript(struct mp_script_args *args)
+{
+    struct script_ctx *ctx = talloc_ptrtype(NULL, ctx);
+    *ctx = (struct script_ctx) {
+        .client = args->client,
+        .mpctx = args->mpctx,
+        .log = args->log,
+        .last_error_str = talloc_strdup(ctx, "Cannot initialize JavaScript"),
+        .filename = args->filename,
+        .path = args->path,
+        .js_malloc_size = 0,
+        .stats = stats_ctx_create(ctx, args->mpctx->global,
+                    mp_tprintf(80, "script/%s", mpv_client_name(args->client))),
+    };
+
+    stats_register_thread_cputime(ctx->stats, "cpu");
+
+    js_Alloc alloc_fn = NULL;
+    void *actx = NULL;
+
+    if (args->mpctx->opts->js_memory_report) {
+        alloc_fn = mp_js_alloc;
+        actx = ctx;
+    }
+
+    int r = -1;
+    js_State *J = js_newstate(alloc_fn, actx, 0);
+    if (!J || s_init_js(J, ctx))
+        goto error_out;
+
+    set_last_error(ctx, 0, NULL);
+    if (js_pcall(J, 0)) {  // script__run_script
+        s_top_to_last_error(ctx, J);
+        goto error_out;
+    }
+
+    r = 0;
+
+error_out:
+    if (r)
+        MP_FATAL(ctx, "%s\n", ctx->last_error_str);
+    if (J)
+        js_freestate(J);
+
+    talloc_free(ctx);
+    return r;
+}
+
+/**********************************************************************
+ *  Main mp.* scripting APIs and helpers
+ *********************************************************************/
+// Return the index in opts of stack[idx] (or of def if undefined), else throws.
+static int checkopt(js_State *J, int idx, const char *def, const char *opts[],
+                    const char *desc)
+{
+    const char *opt = js_isundefined(J, idx) ? def : js_tostring(J, idx);
+    for (int i = 0; opts[i]; i++) {
+        if (strcmp(opt, opts[i]) == 0)
+            return i;
+    }
+    js_error(J, "Invalid %s '%s'", desc, opt);
+}
+
+// args: level as string and a variable numbers of args to print. adds final \n
+static void script_log(js_State *J)
+{
+    const char *level = js_tostring(J, 1);
+    int msgl = mp_msg_find_level(level);
+    if (msgl < 0)
+        js_error(J, "Invalid log level '%s'", level);
+
+    struct mp_log *log = jctx(J)->log;
+    for (int top = js_gettop(J), i = 2; i < top; i++)
+        mp_msg(log, msgl, (i == 2 ? "%s" : " %s"), js_tostring(J, i));
+    mp_msg(log, msgl, "\n");
+    push_success(J);
+}
+
+static void script_find_config_file(js_State *J, void *af)
+{
+    const char *fname = js_tostring(J, 1);
+    char *path = mp_find_config_file(af, jctx(J)->mpctx->global, fname);
+    if (path) {
+        js_pushstring(J, path);
+    } else {
+        push_failure(J, "not found");
+    }
+}
+
+static void script__request_event(js_State *J)
+{
+    const char *event = js_tostring(J, 1);
+    bool enable = js_toboolean(J, 2);
+
+    for (int n = 0; n < 256; n++) {
+        // some n's may be missing ("holes"), returning NULL
+        const char *name = mpv_event_name(n);
+        if (name && strcmp(name, event) == 0) {
+            push_status(J, mpv_request_event(jclient(J), n, enable));
+            return;
+        }
+    }
+    push_failure(J, "Unknown event name");
+}
+
+static void script_enable_messages(js_State *J)
+{
+    const char *level = js_tostring(J, 1);
+    int e = mpv_request_log_messages(jclient(J), level);
+    if (e == MPV_ERROR_INVALID_PARAMETER)
+        js_error(J, "Invalid log level '%s'", level);
+    push_status(J, e);
+}
+
+// args - command [with arguments] as string
+static void script_command(js_State *J)
+{
+    push_status(J, mpv_command_string(jclient(J), js_tostring(J, 1)));
+}
+
+// args: strings of command and then variable number of arguments
+static void script_commandv(js_State *J)
+{
+    const char *argv[MP_CMD_MAX_ARGS + 1];
+    int length = js_gettop(J) - 1;
+    if (length >= MP_ARRAY_SIZE(argv))
+        js_error(J, "Too many arguments");
+
+    for (int i = 0; i < length; i++)
+        argv[i] = js_tostring(J, 1 + i);
+    argv[length] = NULL;
+    push_status(J, mpv_command(jclient(J), argv));
+}
+
+// args: name, string value
+static void script_set_property(js_State *J)
+{
+    int e = mpv_set_property_string(jclient(J), js_tostring(J, 1),
+                                                js_tostring(J, 2));
+    push_status(J, e);
+}
+
+// args: name, boolean
+static void script_set_property_bool(js_State *J)
+{
+    int v = js_toboolean(J, 2);
+    int e = mpv_set_property(jclient(J), js_tostring(J, 1), MPV_FORMAT_FLAG, &v);
+    push_status(J, e);
+}
+
+// args: name [,def]
+static void script_get_property_number(js_State *J)
+{
+    double result;
+    const char *name = js_tostring(J, 1);
+    int e = mpv_get_property(jclient(J), name, MPV_FORMAT_DOUBLE, &result);
+    if (!pushed_error(J, e, 2))
+        js_pushnumber(J, result);
+}
+
+// args: name, native value
+static void script_set_property_native(js_State *J, void *af)
+{
+    mpv_node node;
+    makenode(af, &node, J, 2);
+    mpv_handle *h = jclient(J);
+    int e = mpv_set_property(h, js_tostring(J, 1), MPV_FORMAT_NODE, &node);
+    push_status(J, e);
+}
+
+// args: name [,def]
+static void script_get_property(js_State *J, void *af)
+{
+    mpv_handle *h = jclient(J);
+    char *res = NULL;
+    int e = mpv_get_property(h, js_tostring(J, 1), MPV_FORMAT_STRING, &res);
+    if (e >= 0)
+        add_af_mpv_alloc(af, res);
+    if (!pushed_error(J, e, 2))
+        js_pushstring(J, res);
+}
+
+// args: name
+static void script_del_property(js_State *J)
+{
+    int e = mpv_del_property(jclient(J), js_tostring(J, 1));
+    push_status(J, e);
+}
+
+// args: name [,def]
+static void script_get_property_bool(js_State *J)
+{
+    int result;
+    mpv_handle *h = jclient(J);
+    int e = mpv_get_property(h, js_tostring(J, 1), MPV_FORMAT_FLAG, &result);
+    if (!pushed_error(J, e, 2))
+        js_pushboolean(J, result);
+}
+
+// args: name, number
+static void script_set_property_number(js_State *J)
+{
+    double v = js_tonumber(J, 2);
+    mpv_handle *h = jclient(J);
+    int e = mpv_set_property(h, js_tostring(J, 1), MPV_FORMAT_DOUBLE, &v);
+    push_status(J, e);
+}
+
+// args: name [,def]
+static void script_get_property_native(js_State *J, void *af)
+{
+    const char *name = js_tostring(J, 1);
+    mpv_handle *h = jclient(J);
+    mpv_node *presult_node = new_af_mpv_node(af);
+    int e = mpv_get_property(h, name, MPV_FORMAT_NODE, presult_node);
+    if (!pushed_error(J, e, 2))
+        pushnode(J, presult_node);
+}
+
+// args: name [,def]
+static void script_get_property_osd(js_State *J, void *af)
+{
+    const char *name = js_tostring(J, 1);
+    mpv_handle *h = jclient(J);
+    char *res = NULL;
+    int e = mpv_get_property(h, name, MPV_FORMAT_OSD_STRING, &res);
+    if (e >= 0)
+        add_af_mpv_alloc(af, res);
+    if (!pushed_error(J, e, 2))
+        js_pushstring(J, res);
+}
+
+// args: id, name, type
+static void script__observe_property(js_State *J)
+{
+    const char *fmts[] = {"none", "native", "bool", "string", "number", NULL};
+    const mpv_format mf[] = {MPV_FORMAT_NONE, MPV_FORMAT_NODE, MPV_FORMAT_FLAG,
+                             MPV_FORMAT_STRING, MPV_FORMAT_DOUBLE};
+
+    mpv_format f = mf[checkopt(J, 3, "none", fmts, "observe type")];
+    int e = mpv_observe_property(jclient(J), jsL_checkuint64(J, 1),
+                                             js_tostring(J, 2),
+                                             f);
+    push_status(J, e);
+}
+
+// args: id
+static void script__unobserve_property(js_State *J)
+{
+    int e = mpv_unobserve_property(jclient(J), jsL_checkuint64(J, 1));
+    push_status(J, e);
+}
+
+// args: native (array of command and args, similar to commandv) [,def]
+static void script_command_native(js_State *J, void *af)
+{
+    mpv_node cmd;
+    makenode(af, &cmd, J, 1);
+    mpv_node *presult_node = new_af_mpv_node(af);
+    int e = mpv_command_node(jclient(J), &cmd, presult_node);
+    if (!pushed_error(J, e, 2))
+        pushnode(J, presult_node);
+}
+
+// args: async-command-id, native-command
+static void script__command_native_async(js_State *J, void *af)
+{
+    uint64_t id = jsL_checkuint64(J, 1);
+    struct mpv_node node;
+    makenode(af, &node, J, 2);
+    push_status(J, mpv_command_node_async(jclient(J), id, &node));
+}
+
+// args: async-command-id
+static void script__abort_async_command(js_State *J)
+{
+    mpv_abort_async_command(jclient(J), jsL_checkuint64(J, 1));
+    push_success(J);
+}
+
+// args: none, result in millisec
+static void script_get_time_ms(js_State *J)
+{
+    js_pushnumber(J, mpv_get_time_us(jclient(J)) / (double)(1000));
+}
+
+// push object with properties names (NULL terminated) with respective vals
+static void push_nums_obj(js_State *J, const char * const names[],
+                          const double vals[])
+{
+    js_newobject(J);
+    for (int i = 0; names[i]; i++) {
+        js_pushnumber(J, vals[i]);
+        js_setproperty(J, -2, names[i]);
+    }
+}
+
+// args: input-section-name, x0, y0, x1, y1
+static void script_input_set_section_mouse_area(js_State *J)
+{
+    char *section = (char *)js_tostring(J, 1);
+    mp_input_set_section_mouse_area(jctx(J)->mpctx->input, section,
+        jsL_checkint(J, 2), jsL_checkint(J, 3),   // x0, y0
+        jsL_checkint(J, 4), jsL_checkint(J, 5));  // x1, y1
+    push_success(J);
+}
+
+// args: time-in-ms [,format-string]
+static void script_format_time(js_State *J, void *af)
+{
+    double t = js_tonumber(J, 1);
+    const char *fmt = js_isundefined(J, 2) ? "%H:%M:%S" : js_tostring(J, 2);
+    char *r = talloc_steal(af, mp_format_time_fmt(fmt, t));
+    if (!r)
+        js_error(J, "Invalid time format string '%s'", fmt);
+    js_pushstring(J, r);
+}
+
+// TODO: untested
+static void script_get_wakeup_pipe(js_State *J)
+{
+    js_pushnumber(J, mpv_get_wakeup_pipe(jclient(J)));
+}
+
+// args: name (str), priority (int), id (uint)
+static void script__hook_add(js_State *J)
+{
+    const char *name = js_tostring(J, 1);
+    int pri = jsL_checkint(J, 2);
+    uint64_t id = jsL_checkuint64(J, 3);
+    push_status(J, mpv_hook_add(jclient(J), id, name, pri));
+}
+
+// args: id (uint)
+static void script__hook_continue(js_State *J)
+{
+    push_status(J, mpv_hook_continue(jclient(J), jsL_checkuint64(J, 1)));
+}
+
+/**********************************************************************
+ *  mp.utils
+ *********************************************************************/
+
+// args: [path [,filter]]
+static void script_readdir(js_State *J, void *af)
+{
+    //                    0      1        2       3
+    const char *filters[] = {"all", "files", "dirs", "normal", NULL};
+    const char *path = js_isundefined(J, 1) ? "." : js_tostring(J, 1);
+    int t = checkopt(J, 2, "normal", filters, "listing filter");
+
+    DIR *dir = opendir(path);
+    if (!dir) {
+        push_failure(J, "Cannot open dir");
+        return;
+    }
+    add_af_dir(af, dir);
+    set_last_error(jctx(J), 0, NULL);
+    js_newarray(J);  // the return value
+    char *fullpath = talloc_strdup(af, "");
+    struct dirent *e;
+    int n = 0;
+    while ((e = readdir(dir))) {
+        char *name = e->d_name;
+        if (t) {
+            if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
+                continue;
+            if (fullpath)
+                fullpath[0] = '\0';
+            fullpath = talloc_asprintf_append(fullpath, "%s/%s", path, name);
+            struct stat st;
+            if (stat(fullpath, &st))
+                continue;
+            if (!(((t & 1) && S_ISREG(st.st_mode)) ||
+                  ((t & 2) && S_ISDIR(st.st_mode))))
+            {
+                continue;
+            }
+        }
+        js_pushstring(J, name);
+        js_setindex(J, -2, n++);
+    }
+}
+
+static void script_file_info(js_State *J)
+{
+    const char *path = js_tostring(J, 1);
+
+    struct stat statbuf;
+    if (stat(path, &statbuf) != 0) {
+        push_failure(J, "Cannot stat path");
+        return;
+    }
+    // Clear last error
+    set_last_error(jctx(J), 0, NULL);
+
+    const char * stat_names[] = {
+        "mode", "size",
+        "atime", "mtime", "ctime", NULL
+    };
+    const double stat_values[] = {
+        statbuf.st_mode,
+        statbuf.st_size,
+        statbuf.st_atime,
+        statbuf.st_mtime,
+        statbuf.st_ctime
+    };
+    // Create an object and add all fields
+    push_nums_obj(J, stat_names, stat_values);
+
+    // Convenience booleans
+    js_pushboolean(J, S_ISREG(statbuf.st_mode));
+    js_setproperty(J, -2, "is_file");
+
+    js_pushboolean(J, S_ISDIR(statbuf.st_mode));
+    js_setproperty(J, -2, "is_dir");
+}
+
+
+static void script_split_path(js_State *J)
+{
+    const char *p = js_tostring(J, 1);
+    bstr fname = mp_dirname(p);
+    js_newarray(J);
+    js_pushlstring(J, fname.start, fname.len);
+    js_setindex(J, -2, 0);
+    js_pushstring(J, mp_basename(p));
+    js_setindex(J, -2, 1);
+}
+
+static void script_join_path(js_State *J, void *af)
+{
+    js_pushstring(J, mp_path_join(af, js_tostring(J, 1), js_tostring(J, 2)));
+}
+
+// args: is_append, prefixed file name, data (c-str)
+static void script__write_file(js_State *J, void *af)
+{
+    static const char *prefix = "file://";
+    bool append = js_toboolean(J, 1);
+    const char *fname = js_tostring(J, 2);
+    const char *data = js_tostring(J, 3);
+    const char *opstr = append ? "append" : "write";
+
+    if (strstr(fname, prefix) != fname)  // simple protection for incorrect use
+        js_error(J, "File name must be prefixed with '%s'", prefix);
+    fname += strlen(prefix);
+    fname = mp_get_user_path(af, jctx(J)->mpctx->global, fname);
+    MP_VERBOSE(jctx(J), "%s file '%s'\n", opstr, fname);
+
+    FILE *f = fopen(fname, append ? "ab" : "wb");
+    if (!f)
+        js_error(J, "Cannot open (%s) file: '%s'", opstr, fname);
+    add_af_file(af, f);
+
+    int len = strlen(data);  // limited by terminating null
+    int wrote = fwrite(data, 1, len, f);
+    if (len != wrote)
+        js_error(J, "Cannot %s to file: '%s'", opstr, fname);
+    js_pushboolean(J, 1);  // success. doesn't touch last_error
+}
+
+// args: env var name
+static void script_getenv(js_State *J)
+{
+    const char *v = getenv(js_tostring(J, 1));
+    if (v) {
+        js_pushstring(J, v);
+    } else {
+        js_pushundefined(J);
+    }
+}
+
+// args: none
+static void script_get_env_list(js_State *J)
+{
+    js_newarray(J);
+    for (int n = 0; environ && environ[n]; n++) {
+        js_pushstring(J, environ[n]);
+        js_setindex(J, -2, n);
+    }
+}
+
+// args: as-filename, content-string, returns the compiled result as a function
+static void script_compile_js(js_State *J)
+{
+    js_loadstring(J, js_tostring(J, 1), js_tostring(J, 2));
+}
+
+// args: true = print info (with the warning report function - no info report)
+static void script__gc(js_State *J)
+{
+    js_gc(J, js_toboolean(J, 1) ? 1 : 0);
+    push_success(J);
+}
+
+/**********************************************************************
+ *  Core functions: pushnode, makenode and the event loop backend
+ *********************************************************************/
+
+// pushes a js value/array/object from an mpv_node
+static void pushnode(js_State *J, mpv_node *node)
+{
+    int len;
+    switch (node->format) {
+    case MPV_FORMAT_NONE:   js_pushnull(J); break;
+    case MPV_FORMAT_STRING: js_pushstring(J, node->u.string); break;
+    case MPV_FORMAT_INT64:  js_pushnumber(J, node->u.int64); break;
+    case MPV_FORMAT_DOUBLE: js_pushnumber(J, node->u.double_); break;
+    case MPV_FORMAT_FLAG:   js_pushboolean(J, node->u.flag); break;
+    case MPV_FORMAT_BYTE_ARRAY:
+        js_pushlstring(J, node->u.ba->data, node->u.ba->size);
+        break;
+    case MPV_FORMAT_NODE_ARRAY:
+        js_newarray(J);
+        len = node->u.list->num;
+        for (int n = 0; n < len; n++) {
+            pushnode(J, &node->u.list->values[n]);
+            js_setindex(J, -2, n);
+        }
+        break;
+    case MPV_FORMAT_NODE_MAP:
+        js_newobject(J);
+        len = node->u.list->num;
+        for (int n = 0; n < len; n++) {
+            pushnode(J, &node->u.list->values[n]);
+            js_setproperty(J, -2, node->u.list->keys[n]);
+        }
+        break;
+    default:
+        js_pushstring(J, "[UNSUPPORTED_MPV_FORMAT]");
+        break;
+    }
+}
+
+// For the object at stack index idx, extract the (own) property names into
+// keys array (and allocate it to accommodate) and return the number of keys.
+static int get_obj_properties(void *ta_ctx, char ***keys, js_State *J, int idx)
+{
+    int length = 0;
+    js_pushiterator(J, idx, 1);
+
+    *keys = talloc_new(ta_ctx);
+    const char *name;
+    while ((name = js_nextiterator(J, -1)))
+        MP_TARRAY_APPEND(ta_ctx, *keys, length, talloc_strdup(ta_ctx, name));
+
+    js_pop(J, 1);  // the iterator
+    return length;
+}
+
+// true if we don't lose (too much) precision when casting to int64
+static bool same_as_int64(double d)
+{
+    // The range checks also validly filter inf and nan, so behavior is defined
+    return d >= INT64_MIN && d <= (double) INT64_MAX && d == (int64_t)d;
+}
+
+static int jsL_checkint(js_State *J, int idx)
+{
+    double d = js_tonumber(J, idx);
+    if (!(d >= INT_MIN && d <= INT_MAX))
+        js_error(J, "int out of range at index %d", idx);
+    return d;
+}
+
+static uint64_t jsL_checkuint64(js_State *J, int idx)
+{
+    double d = js_tonumber(J, idx);
+    if (!(d >= 0 && d <= (double) UINT64_MAX))
+        js_error(J, "uint64 out of range at index %d", idx);
+    return d;
+}
+
+// From the js stack value/array/object at index idx
+static void makenode(void *ta_ctx, mpv_node *dst, js_State *J, int idx)
+{
+    if (js_isundefined(J, idx) || js_isnull(J, idx)) {
+        dst->format = MPV_FORMAT_NONE;
+
+    } else if (js_isboolean(J, idx)) {
+        dst->format = MPV_FORMAT_FLAG;
+        dst->u.flag = js_toboolean(J, idx);
+
+    } else if (js_isnumber(J, idx)) {
+        double val = js_tonumber(J, idx);
+        if (same_as_int64(val)) {  // use int, because we can
+            dst->format = MPV_FORMAT_INT64;
+            dst->u.int64 = val;
+        } else {
+            dst->format = MPV_FORMAT_DOUBLE;
+            dst->u.double_ = val;
+        }
+
+    } else if (js_isarray(J, idx)) {
+        dst->format = MPV_FORMAT_NODE_ARRAY;
+        dst->u.list = talloc(ta_ctx, struct mpv_node_list);
+        dst->u.list->keys = NULL;
+
+        int length = js_getlength(J, idx);
+        dst->u.list->num = length;
+        dst->u.list->values = talloc_array(ta_ctx, mpv_node, length);
+        for (int n = 0; n < length; n++) {
+            js_getindex(J, idx, n);
+            makenode(ta_ctx, &dst->u.list->values[n], J, -1);
+            js_pop(J, 1);
+        }
+
+    } else if (js_isobject(J, idx)) {
+        dst->format = MPV_FORMAT_NODE_MAP;
+        dst->u.list = talloc(ta_ctx, struct mpv_node_list);
+
+        int length = get_obj_properties(ta_ctx, &dst->u.list->keys, J, idx);
+        dst->u.list->num = length;
+        dst->u.list->values = talloc_array(ta_ctx, mpv_node, length);
+        for (int n = 0; n < length; n++) {
+            js_getproperty(J, idx, dst->u.list->keys[n]);
+            makenode(ta_ctx, &dst->u.list->values[n], J, -1);
+            js_pop(J, 1);
+        }
+
+    } else {  // string, or anything else as string
+        dst->format = MPV_FORMAT_STRING;
+        dst->u.string = talloc_strdup(ta_ctx, js_tostring(J, idx));
+    }
+}
+
+// args: wait in secs (infinite if negative) if mpv doesn't send events earlier.
+static void script_wait_event(js_State *J, void *af)
+{
+    double timeout = js_isnumber(J, 1) ? js_tonumber(J, 1) : -1;
+    mpv_event *event = mpv_wait_event(jclient(J), timeout);
+
+    mpv_node *rn = new_af_mpv_node(af);
+    mpv_event_to_node(rn, event);
+    pushnode(J, rn);
+}
+
+/**********************************************************************
+ *  Script functions setup
+ *********************************************************************/
+#define FN_ENTRY(name, length) {#name, length, script_ ## name, NULL}
+#define AF_ENTRY(name, length) {#name, length, NULL, script_ ## name}
+struct fn_entry {
+    const char *name;
+    int length;
+    js_CFunction jsc_fn;
+    af_CFunction afc_fn;
+};
+
+// Names starting with underscore are wrapped at @defaults.js
+// FN_ENTRY is a normal js C function, AF_ENTRY is an autofree js C function.
+static const struct fn_entry main_fns[] = {
+    FN_ENTRY(log, 1),
+    AF_ENTRY(wait_event, 1),
+    FN_ENTRY(_request_event, 2),
+    AF_ENTRY(find_config_file, 1),
+    FN_ENTRY(command, 1),
+    FN_ENTRY(commandv, 0),
+    AF_ENTRY(command_native, 2),
+    AF_ENTRY(_command_native_async, 2),
+    FN_ENTRY(_abort_async_command, 1),
+    FN_ENTRY(del_property, 1),
+    FN_ENTRY(get_property_bool, 2),
+    FN_ENTRY(get_property_number, 2),
+    AF_ENTRY(get_property_native, 2),
+    AF_ENTRY(get_property, 2),
+    AF_ENTRY(get_property_osd, 2),
+    FN_ENTRY(set_property, 2),
+    FN_ENTRY(set_property_bool, 2),
+    FN_ENTRY(set_property_number, 2),
+    AF_ENTRY(set_property_native, 2),
+    FN_ENTRY(_observe_property, 3),
+    FN_ENTRY(_unobserve_property, 1),
+    FN_ENTRY(get_time_ms, 0),
+    AF_ENTRY(format_time, 2),
+    FN_ENTRY(enable_messages, 1),
+    FN_ENTRY(get_wakeup_pipe, 0),
+    FN_ENTRY(_hook_add, 3),
+    FN_ENTRY(_hook_continue, 1),
+    FN_ENTRY(input_set_section_mouse_area, 5),
+    FN_ENTRY(last_error, 0),
+    FN_ENTRY(_set_last_error, 1),
+    {0}
+};
+
+static const struct fn_entry utils_fns[] = {
+    AF_ENTRY(readdir, 2),
+    FN_ENTRY(file_info, 1),
+    FN_ENTRY(split_path, 1),
+    AF_ENTRY(join_path, 2),
+    FN_ENTRY(get_env_list, 0),
+
+    FN_ENTRY(read_file, 2),
+    AF_ENTRY(_write_file, 3),
+    FN_ENTRY(getenv, 1),
+    FN_ENTRY(compile_js, 2),
+    FN_ENTRY(_gc, 1),
+    {0}
+};
+
+// Adds an object <module> with the functions at e to the top object
+static void add_package_fns(js_State *J, const char *module,
+                            const struct fn_entry *e)
+{
+    js_newobject(J);
+    for (int n = 0; e[n].name; n++) {
+        if (e[n].jsc_fn) {
+            js_newcfunction(J, e[n].jsc_fn, e[n].name, e[n].length);
+        } else {
+            af_newcfunction(J, e[n].afc_fn, e[n].name, e[n].length);
+        }
+        js_setproperty(J, -2, e[n].name);
+    }
+    js_setproperty(J, -2, module);
+}
+
+// Called directly, adds functions/vars to the caller's this.
+static void add_functions(js_State *J, struct script_ctx *ctx)
+{
+    js_copy(J, 0);
+    add_package_fns(J, "mp", main_fns);
+    js_getproperty(J, 0, "mp");  // + this mp
+    add_package_fns(J, "utils", utils_fns);
+
+    js_pushstring(J, mpv_client_name(ctx->client));
+    js_setproperty(J, -2, "script_name");
+
+    js_pushstring(J, ctx->filename);
+    js_setproperty(J, -2, "script_file");
+
+    if (ctx->path) {
+        js_pushstring(J, ctx->path);
+        js_setproperty(J, -2, "script_path");
+    }
+
+    js_pop(J, 2);  // leave the stack as we got it
+}
+
+// main export of this file, used by cplayer to load js scripts
+const struct mp_scripting mp_scripting_js = {
+    .name = "js",
+    .file_ext = "js",
+    .load = s_load_javascript,
+};
diff --git a/player/javascript/defaults.js b/player/javascript/defaults.js
new file mode 100644
index 0000000..d906ec2
--- /dev/null
+++ b/player/javascript/defaults.js
@@ -0,0 +1,782 @@
+"use strict";
+(function main_default_js(g) {
+// - g is the global object.
+// - User callbacks called without 'this', global only if callee is non-strict.
+// - The names of function expressions are not required, but are used in stack
+//   traces. We name them where useful to show up (fname:#line always shows).
+
+mp.msg = { log: mp.log };
+mp.msg.verbose = mp.log.bind(null, "v");
+var levels = ["fatal", "error", "warn", "info", "debug", "trace"];
+levels.forEach(function(l) { mp.msg[l] = mp.log.bind(null, l) });
+
+// same as {} but without inherited stuff, e.g. o["toString"] doesn't exist.
+// used where we try to fetch items by keys which we don't absolutely trust.
+function new_cache() {
+    return Object.create(null, {});
+}
+
+/**********************************************************************
+ *  event handlers, property observers, idle, client messages, hooks, async
+ *********************************************************************/
+var ehandlers = new_cache() // items of event-name: array of {maybe cb: fn}
+
+mp.register_event = function(name, fn) {
+    if (!ehandlers[name])
+        ehandlers[name] = [];
+    ehandlers[name] = ehandlers[name].concat([{cb: fn}]);  // replaces the arr
+    return mp._request_event(name, true);
+}
+
+mp.unregister_event = function(fn) {
+    for (var name in ehandlers) {
+        ehandlers[name] = ehandlers[name].filter(function(h) {
+                              if (h.cb != fn)
+                                  return true;
+                              delete h.cb;  // dispatch could have a ref to h
+                          });  // replacing, not mutating the array
+        if (!ehandlers[name].length) {
+            delete ehandlers[name];
+            mp._request_event(name, false);
+        }
+    }
+}
+
+// call only pre-registered handlers, but not ones which got unregistered
+function dispatch_event(e) {
+    var handlers = ehandlers[e.event];
+    if (handlers) {
+        for (var len = handlers.length, i = 0; i < len; i++) {
+            var cb = handlers[i].cb;  // 'handlers' won't mutate, but unregister
+            if (cb)                   // could remove cb from some items
+                cb(e);
+        }
+    }
+}
+
+//  ----- idle observers -----
+var iobservers = [],  // array of callbacks
+    ideleted = false;
+
+mp.register_idle = function(fn) {
+    iobservers.push(fn);
+}
+
+mp.unregister_idle = function(fn) {
+    iobservers.forEach(function(f, i) {
+        if (f == fn)
+             delete iobservers[i];  // -> same length but [more] sparse
+    });
+    ideleted = true;
+}
+
+function notify_idle_observers() {
+    // forEach and filter skip deleted items and newly added items
+    iobservers.forEach(function(f) { f() });
+    if (ideleted) {
+        iobservers = iobservers.filter(function() { return true });
+        ideleted = false;
+    }
+}
+
+//  ----- property observers -----
+var next_oid = 1,
+    observers = new_cache();  // items of id: fn
+
+mp.observe_property = function(name, format, fn) {
+    var id = next_oid++;
+    observers[id] = fn;
+    return mp._observe_property(id, name, format || undefined);  // allow null
+}
+
+mp.unobserve_property = function(fn) {
+    for (var id in observers) {
+        if (observers[id] == fn) {
+            delete observers[id];
+            mp._unobserve_property(id);
+        }
+    }
+}
+
+function notify_observer(e) {
+    var cb = observers[e.id];
+    if (cb)
+        cb(e.name, e.data);
+}
+
+//  -----  Client messages -----
+var messages = new_cache();  // items of name: fn
+
+// overrides name. no libmpv API to reg/unreg specific messages.
+mp.register_script_message = function(name, fn) {
+    messages[name] = fn;
+}
+
+mp.unregister_script_message = function(name) {
+    delete messages[name];
+}
+
+function dispatch_message(ev) {
+    var cb = ev.args.length ? messages[ev.args[0]] : false;
+    if (cb)
+        cb.apply(null, ev.args.slice(1));
+}
+
+//  ----- hooks -----
+var hooks = [];  // array of callbacks, id is index+1
+
+function run_hook(ev) {
+    var state = 0;  // 0:initial, 1:deferred, 2:continued
+    function do_cont() { return state = 2, mp._hook_continue(ev.hook_id) }
+
+    function err() { return mp.msg.error("hook already continued"), undefined }
+    function usr_defer() { return state == 2 ? err() : (state = 1, true) }
+    function usr_cont()  { return state == 2 ? err() : do_cont() }
+
+    var cb = ev.id > 0 && hooks[ev.id - 1];
+    if (cb)
+        cb({ defer: usr_defer, cont: usr_cont });
+    return state == 0 ? do_cont() : true;
+}
+
+mp.add_hook = function add_hook(name, pri, fn) {
+    hooks.push(fn);
+    // 50 (scripting docs default priority) maps to 0 (default in C API docs)
+    return mp._hook_add(name, pri - 50, hooks.length);
+}
+
+// ----- async commands -----
+var async_callbacks = new_cache();  // items of id: fn
+var async_next_id = 1;
+
+mp.command_native_async = function command_native_async(node, cb) {
+    var id = async_next_id++;
+    cb = cb || function dummy() {};
+    if (!mp._command_native_async(id, node)) {
+        var le = mp.last_error();
+        setTimeout(cb, 0, false, undefined, le);  /* callback async */
+        mp._set_last_error(le);
+        return undefined;
+    }
+    async_callbacks[id] = cb;
+    return id;
+}
+
+function async_command_handler(ev) {
+    var cb = async_callbacks[ev.id];
+    delete async_callbacks[ev.id];
+    if (ev.error)
+        cb(false, undefined, ev.error);
+    else
+        cb(true, ev.result, "");
+}
+
+mp.abort_async_command = function abort_async_command(id) {
+    // cb will be invoked regardless, possibly with the abort result
+    if (async_callbacks[id])
+        mp._abort_async_command(id);
+}
+
+// shared-script-properties - always an object, even if without properties
+function shared_script_property_set(name, val) {
+    if (arguments.length > 1)
+        return mp.commandv("change-list", "shared-script-properties", "append", "" + name + "=" + val);
+    else
+        return mp.commandv("change-list", "shared-script-properties", "remove", name);
+}
+
+function shared_script_property_get(name) {
+    return mp.get_property_native("shared-script-properties")[name];
+}
+
+function shared_script_property_observe(name, cb) {
+    return mp.observe_property("shared-script-properties", "native",
+        function shared_props_cb(_name, val) { cb(name, val[name]) }
+    );
+}
+
+mp.utils.shared_script_property_set = shared_script_property_set;
+mp.utils.shared_script_property_get = shared_script_property_get;
+mp.utils.shared_script_property_observe = shared_script_property_observe;
+
+// osd-ass
+var next_assid = 1;
+mp.create_osd_overlay = function create_osd_overlay(format) {
+    return {
+        format: format || "ass-events",
+        id: next_assid++,
+        data: "",
+        res_x: 0,
+        res_y: 720,
+        z: 0,
+
+        update: function ass_update() {
+            var cmd = {};  // shallow clone of `this', excluding methods
+            for (var k in this) {
+                if (typeof this[k] != "function")
+                    cmd[k] = this[k];
+            }
+
+            cmd.name = "osd-overlay";
+            cmd.res_x = Math.round(this.res_x);
+            cmd.res_y = Math.round(this.res_y);
+
+            return mp.command_native(cmd);
+        },
+
+        remove: function ass_remove() {
+            mp.command_native({
+                name: "osd-overlay",
+                id: this.id,
+                format: "none",
+                data: "",
+            });
+            return mp.last_error() ? undefined : true;
+        },
+    };
+}
+
+// osd-ass legacy API
+mp.set_osd_ass = function set_osd_ass(res_x, res_y, data) {
+    if (!mp._legacy_overlay)
+        mp._legacy_overlay = mp.create_osd_overlay("ass-events");
+
+    var lo = mp._legacy_overlay;
+    if (lo.res_x == res_x && lo.res_y == res_y && lo.data == data)
+        return true;
+
+    mp._legacy_overlay.res_x = res_x;
+    mp._legacy_overlay.res_y = res_y;
+    mp._legacy_overlay.data = data;
+    return mp._legacy_overlay.update();
+}
+
+// the following return undefined on error, null passthrough, or legacy object
+mp.get_osd_size = function get_osd_size() {
+    var d = mp.get_property_native("osd-dimensions");
+    return d && {width: d.w, height: d.h, aspect: d.aspect};
+}
+mp.get_osd_margins = function get_osd_margins() {
+    var d = mp.get_property_native("osd-dimensions");
+    return d && {left: d.ml, right: d.mr, top: d.mt, bottom: d.mb};
+}
+
+/**********************************************************************
+ *  key bindings
+ *********************************************************************/
+// binds: items of (binding) name which are objects of:
+// {cb: fn, forced: bool, maybe input: str, repeatable: bool, complex: bool}
+var binds = new_cache();
+
+function dispatch_key_binding(name, state, key_name) {
+    var cb = binds[name] ? binds[name].cb : false;
+    if (cb)  // "script-binding [<script_name>/]<name>" command was invoked
+        cb(state, key_name);
+}
+
+var binds_tid = 0;  // flush timer id. actual id's are always true-thy
+mp.flush_key_bindings = function flush_key_bindings() {
+    function prioritized_inputs(arr) {
+        return arr.sort(function(a, b) { return a.id - b.id })
+                  .map(function(bind) { return bind.input });
+    }
+
+    var def = [], forced = [];
+    for (var n in binds)
+        if (binds[n].input)
+            (binds[n].forced ? forced : def).push(binds[n]);
+    // newer bindings for the same key override/hide older ones
+    def = prioritized_inputs(def);
+    forced = prioritized_inputs(forced);
+
+    var sect = "input_" + mp.script_name;
+    mp.commandv("define-section", sect, def.join("\n"), "default");
+    mp.commandv("enable-section", sect, "allow-hide-cursor+allow-vo-dragging");
+
+    sect = "input_forced_" + mp.script_name;
+    mp.commandv("define-section", sect, forced.join("\n"), "force");
+    mp.commandv("enable-section", sect, "allow-hide-cursor+allow-vo-dragging");
+
+    clearTimeout(binds_tid);  // cancel future flush if called directly
+    binds_tid = 0;
+}
+
+function sched_bindings_flush() {
+    if (!binds_tid)
+        binds_tid = setTimeout(mp.flush_key_bindings, 0);  // fires on idle
+}
+
+// name/opts maybe omitted. opts: object with optional bool members: repeatable,
+// complex, forced, or a string str which is evaluated as object {str: true}.
+var next_bid = 1;
+function add_binding(forced, key, name, fn, opts) {
+    if (typeof name == "function") {  // as if "name" is not part of the args
+        opts = fn;
+        fn = name;
+        name = false;
+    }
+    var key_data = {forced: forced};
+    switch (typeof opts) {  // merge opts into key_data
+        case "string": key_data[opts] = true; break;
+        case "object": for (var o in opts) key_data[o] = opts[o];
+    }
+    key_data.id = next_bid++;
+    if (!name)
+        name = "__keybinding" + key_data.id;  // new unique binding name
+
+    if (key_data.complex) {
+        mp.register_script_message(name, function msg_cb() {
+            fn({event: "press", is_mouse: false});
+        });
+        var KEY_STATES = { u: "up", d: "down", r: "repeat", p: "press" };
+        key_data.cb = function key_cb(state, key_name) {
+            fn({
+                event: KEY_STATES[state[0]] || "unknown",
+                is_mouse: state[1] == "m",
+                key_name: key_name || undefined
+            });
+        }
+    } else {
+        mp.register_script_message(name, fn);
+        key_data.cb = function key_cb(state) {
+            // Emulate the semantics at input.c: mouse emits on up, kb on down.
+            // Also, key repeat triggers the binding again.
+            var e = state[0],
+                emit = (state[1] == "m") ? (e == "u") : (e == "d");
+            if (emit || e == "p" || e == "r" && key_data.repeatable)
+                fn();
+        }
+    }
+
+    if (key)
+        key_data.input = key + " script-binding " + mp.script_name + "/" + name;
+    binds[name] = key_data;  // used by user and/or our (key) script-binding
+    sched_bindings_flush();
+}
+
+mp.add_key_binding = add_binding.bind(null, false);
+mp.add_forced_key_binding = add_binding.bind(null, true);
+
+mp.remove_key_binding = function(name) {
+    mp.unregister_script_message(name);
+    delete binds[name];
+    sched_bindings_flush();
+}
+
+/**********************************************************************
+ Timers: compatible HTML5 WindowTimers - set/clear Timeout/Interval
+ - Spec: https://www.w3.org/TR/html5/webappapis.html#timers
+ - Guaranteed to callback a-sync to [re-]insertion (event-loop wise).
+ - Guaranteed to callback by expiration order, or, if equal, by insertion order.
+ - Not guaranteed schedule accuracy, though intervals should have good average.
+ *********************************************************************/
+
+// pending 'timers' ordered by expiration: latest at index 0 (top fires first).
+// Earlier timers are quicker to handle - just push/pop or fewer items to shift.
+var next_tid = 1,
+    timers = [],  // while in process_timers, just insertion-ordered (push)
+    tset_is_push = false,  // signal set_timer that we're in process_timers
+    tcanceled = false,  // or object of items timer-id: true
+    now = mp.get_time_ms;  // just an alias
+
+function insert_sorted(arr, t) {
+    for (var i = arr.length - 1; i >= 0 && t.when >= arr[i].when; i--)
+        arr[i + 1] = arr[i];  // move up timers which fire earlier than t
+    arr[i + 1] = t;  // i is -1 or fires later than t
+}
+
+// args (is "arguments"): fn_or_str [,duration [,user_arg1 [, user_arg2 ...]]]
+function set_timer(repeat, args) {
+    var fos = args[0],
+        duration = Math.max(0, (args[1] || 0)),  // minimum and default are 0
+        t = {
+            id: next_tid++,
+            when: now() + duration,
+            interval: repeat ? duration : -1,
+            callback: (typeof fos == "function") ? fos : Function(fos),
+            args: (args.length < 3) ? false : [].slice.call(args, 2),
+        };
+
+    if (tset_is_push) {
+        timers.push(t);
+    } else {
+        insert_sorted(timers, t);
+    }
+    return t.id;
+}
+
+g.setTimeout  = function setTimeout()  { return set_timer(false, arguments) };
+g.setInterval = function setInterval() { return set_timer(true,  arguments) };
+
+g.clearTimeout = g.clearInterval = function(id) {
+    if (id < next_tid) {  // must ignore if not active timer id.
+        if (!tcanceled)
+            tcanceled = {};
+        tcanceled[id] = true;
+    }
+}
+
+// arr: ordered timers array. ret: -1: no timers, 0: due, positive: ms to wait
+function peek_wait(arr) {
+    return arr.length ? Math.max(0, arr[arr.length - 1].when - now()) : -1;
+}
+
+function peek_timers_wait() {
+    return peek_wait(timers);  // must not be called while in process_timers
+}
+
+// Callback all due non-canceled timers which were inserted before calling us.
+// Returns wait in ms till the next timer (possibly 0), or -1 if nothing pends.
+function process_timers() {
+    var wait = peek_wait(timers);
+    if (wait != 0)
+        return wait;
+
+    var actives = timers;  // only process those already inserted by now
+    timers = [];  // we'll handle added new timers at the end of processing.
+    tset_is_push = true;  // signal set_timer to just push-insert
+
+    do {
+        var t = actives.pop();
+        if (tcanceled && tcanceled[t.id])
+            continue;
+
+        if (t.args) {
+            t.callback.apply(null, t.args);
+        } else {
+            (0, t.callback)();  // faster, nicer stack trace than t.cb.call()
+        }
+
+        if (t.interval >= 0) {
+            // allow 20 ms delay/clock-resolution/gc before we skip and reset
+            t.when = Math.max(now() - 20, t.when + t.interval);
+            timers.push(t);  // insertion order only
+        }
+    } while (peek_wait(actives) == 0);
+
+    // new 'timers' are insertion-ordered. remains of actives are fully ordered
+    timers.forEach(function(t) { insert_sorted(actives, t) });
+    timers = actives;  // now we're fully ordered again, and with all timers
+    tset_is_push = false;
+    if (tcanceled) {
+        timers = timers.filter(function(t) { return !tcanceled[t.id] });
+        tcanceled = false;
+    }
+    return peek_wait(timers);
+}
+
+/**********************************************************************
+ CommonJS module/require
+
+ Spec: http://wiki.commonjs.org/wiki/Modules/1.1.1
+ - All the mandatory requirements are implemented, all the unit tests pass.
+ - The implementation makes the following exception:
+   - Allows the chars [~@:\\] in module id for meta-dir/builtin/dos-drive/UNC.
+
+ Implementation choices beyond the specification:
+ - A module may assign to module.exports (rather than only to exports).
+ - A module's 'this' is the global object, also if it sets strict mode.
+   - No 'global'/'self'. Users can do "this.global = this;" before require(..)
+   - A module has "privacy of its top scope", runs in its own function context.
+ - No id identity with symlinks - a valid choice which others make too.
+ - require("X") always maps to "X.js" -> require("foo.js") is file "foo.js.js".
+ - Global modules search paths are 'scripts/modules.js/' in mpv config dirs.
+ - A main script could e.g. require("./abc") to load a non-global module.
+ - Module id supports mpv path enhancements, e.g. ~/foo, ~~/bar, ~~desktop/baz
+ *********************************************************************/
+
+mp.module_paths = [];  // global modules search paths
+if (mp.script_path !== undefined)  // loaded as a directory
+    mp.module_paths.push(mp.utils.join_path(mp.script_path, "modules"));
+
+// Internal meta top-dirs. Users should not rely on these names.
+var MODULES_META = "~~modules",
+    SCRIPTDIR_META = "~~scriptdir",  // relative script path -> meta absolute id
+    main_script = mp.utils.split_path(mp.script_file);  // -> [ path, file ]
+
+function resolve_module_file(id) {
+    var sep = id.indexOf("/"),
+        base = id.substring(0, sep),
+        rest = id.substring(sep + 1) + ".js";
+
+    if (base == SCRIPTDIR_META)
+        return mp.utils.join_path(main_script[0], rest);
+
+    if (base == MODULES_META) {
+        for (var i = 0; i < mp.module_paths.length; i++) {
+            try {
+                var f = mp.utils.join_path(mp.module_paths[i], rest);
+                mp.utils.read_file(f, 1);  // throws on any error
+                return f;
+            } catch (e) {}
+        }
+        throw(Error("Cannot find module file '" + rest + "'"));
+    }
+
+    return id + ".js";
+}
+
+// Delimiter '/', remove redundancies, prefix with modules meta-root if needed.
+// E.g. c:\x -> c:/x, or ./x//y/../z -> ./x/z, or utils/x -> ~~modules/utils/x .
+function canonicalize(id) {
+    var path = id.replace(/\\/g,"/").split("/"),
+        t = path[0],
+        base = [];
+
+    // if not strictly relative then must be top-level. figure out base/rest
+    if (t != "." && t != "..") {
+        // global module if it's not fs-root/home/dos-drive/builtin/meta-dir
+        if (!(t == "" || t == "~" || t[1] == ":" ||  t == "@" || t.match(/^~~/)))
+            path.unshift(MODULES_META);  // add an explicit modules meta-root
+
+        if (id.match(/^\\\\/))  // simple UNC handling, preserve leading \\srv
+            path = ["\\\\" + path[2]].concat(path.slice(3));  // [ \\srv, shr..]
+
+        if (t[1] == ":" && t.length > 2) {  // path: [ "c:relative", "path" ]
+            path[0] = t.substring(2);
+            path.unshift(t[0] + ":.");  //  ->  [ "c:.", "relative", "path" ]
+        }
+        base = [path.shift()];
+    }
+
+    // path is now logically relative. base, if not empty, is its [meta] root.
+    // normalize the relative part - always id-based (spec Module Id, 1.3.6).
+    var cr = [];  // canonicalized relative
+    for (var i = 0; i < path.length; i++) {
+        if (path[i] == "." || path[i] == "")
+            continue;
+        if (path[i] == ".." && cr.length && cr[cr.length - 1] != "..") {
+            cr.pop();
+            continue;
+        }
+        cr.push(path[i]);
+    }
+
+    if (!base.length && cr[0] != "..")
+        base = ["."];  // relative and not ../<stuff> so must start with ./
+    return base.concat(cr).join("/");
+}
+
+function resolve_module_id(base_id, new_id) {
+    new_id = canonicalize(new_id);
+    if (!new_id.match(/^\.\/|^\.\.\//))  // doesn't start with ./ or ../
+        return new_id;  // not relative, we don't care about base_id
+
+    var combined = mp.utils.join_path(mp.utils.split_path(base_id)[0], new_id);
+    return canonicalize(combined);
+}
+
+var req_cache = new_cache();  // global for all instances of require
+
+// ret: a require function instance which uses base_id to resolve relative id's
+function new_require(base_id) {
+    return function require(id) {
+        id = resolve_module_id(base_id, id);  // id is now top-level
+        if (req_cache[id])
+            return req_cache[id].exports;
+
+        var new_module = {id: id, exports: {}};
+        req_cache[id] = new_module;
+        try {
+            var filename = resolve_module_file(id);
+            // we need dedicated free vars + filename in traces + allow strict
+            var str = "mp._req = function(require, exports, module) {" +
+                          mp.utils.read_file(filename) +
+                      "\n;}";
+            mp.utils.compile_js(filename, str)();  // only runs the assignment
+            var tmp = mp._req;  // we have mp._req, or else we'd have thrown
+            delete mp._req;
+            tmp.call(g, new_require(id), new_module.exports, new_module);
+        } catch (e) {
+            delete req_cache[id];
+            throw(e);
+        }
+
+        return new_module.exports;
+    };
+}
+
+g.require = new_require(SCRIPTDIR_META + "/" + main_script[1]);
+
+/**********************************************************************
+ *  mp.options
+ *********************************************************************/
+function read_options(opts, id, on_update, conf_override) {
+    id = String(id ? id : mp.get_script_name());
+    mp.msg.debug("reading options for " + id);
+
+    var conf, fname = "~~/script-opts/" + id + ".conf";
+    try {
+        conf = arguments.length > 3 ? conf_override : mp.utils.read_file(fname);
+    } catch (e) {
+        mp.msg.verbose(fname + " not found.");
+    }
+
+    // data as config file lines array, or empty array
+    var data = conf ? conf.replace(/\r\n/g, "\n").split("\n") : [],
+        conf_len = data.length;  // before we append script-opts below
+
+    // Append relevant script-opts as <key-sans-id>=<value> to data
+    var sopts = mp.get_property_native("options/script-opts"),
+        prefix = id + "-";
+    for (var key in sopts) {
+        if (key.indexOf(prefix) == 0)
+            data.push(key.substring(prefix.length) + "=" + sopts[key]);
+    }
+
+    // Update opts from data
+    data.forEach(function(line, i) {
+        if (line[0] == "#" || line.trim() == "")
+            return;
+
+        var key = line.substring(0, line.indexOf("=")),
+            val = line.substring(line.indexOf("=") + 1),
+            type = typeof opts[key],
+            info = i < conf_len ? fname + ":" + (i + 1)  // 1-based line number
+                                : "script-opts:" + prefix + key;
+
+        if (!opts.hasOwnProperty(key))
+            mp.msg.warn(info, "Ignoring unknown key '" + key + "'");
+        else if (type == "string")
+            opts[key] = val;
+        else if (type == "boolean" && (val == "yes" || val == "no"))
+            opts[key] = (val == "yes");
+        else if (type == "number" && val.trim() != "" && !isNaN(val))
+            opts[key] = Number(val);
+        else
+            mp.msg.error(info, "Error: can't convert '" + val + "' to " + type);
+    });
+
+    if (on_update) {
+        mp.observe_property("options/script-opts", "native", function(_n, _v) {
+            var saved = JSON.parse(JSON.stringify(opts));  // clone
+            var changelist = {}, changed = false;
+            read_options(opts, id, 0, conf);  // re-apply orig-file + script-opts
+            for (var key in opts) {
+                if (opts[key] != saved[key])  // type always stays the same
+                    changelist[key] = changed = true;
+            }
+            if (changed)
+                on_update(changelist);
+        });
+    }
+}
+
+mp.options = { read_options: read_options };
+
+/**********************************************************************
+ *  various
+ *********************************************************************/
+g.print = mp.msg.info;  // convenient alias
+mp.get_script_name = function() { return mp.script_name };
+mp.get_script_file = function() { return mp.script_file };
+mp.get_script_directory = function() { return mp.script_path };
+mp.get_time = function() { return mp.get_time_ms() / 1000 };
+mp.utils.getcwd = function() { return mp.get_property("working-directory") };
+mp.utils.getpid = function() { return mp.get_property_number("pid") }
+mp.utils.get_user_path =
+    function(p) { return mp.command_native(["expand-path", String(p)]) };
+mp.get_mouse_pos = function() { return mp.get_property_native("mouse-pos") };
+mp.utils.write_file = mp.utils._write_file.bind(null, false);
+mp.utils.append_file = mp.utils._write_file.bind(null, true);
+mp.dispatch_event = dispatch_event;
+mp.process_timers = process_timers;
+mp.notify_idle_observers = notify_idle_observers;
+mp.peek_timers_wait = peek_timers_wait;
+
+mp.get_opt = function(key, def) {
+    var v = mp.get_property_native("options/script-opts")[key];
+    return (typeof v != "undefined") ? v : def;
+}
+
+mp.osd_message = function osd_message(text, duration) {
+    mp.commandv("show_text", text, Math.round(1000 * (duration || -1)));
+}
+
+mp.utils.subprocess = function subprocess(t) {
+    var cmd = { name: "subprocess", capture_stdout: true };
+    var new_names = { cancellable: "playback_only", max_size: "capture_size" };
+    for (var k in t)
+        cmd[new_names[k] || k] = t[k];
+
+    var rv = mp.command_native(cmd);
+    if (mp.last_error())  /* typically on missing/incorrect args */
+        rv = { error_string: mp.last_error(), status: -1 };
+    if (rv.error_string)
+        rv.error = rv.error_string;
+    return rv;
+}
+
+mp.utils.subprocess_detached = function subprocess_detached(t) {
+    return mp.commandv.apply(null, ["run"].concat(t.args));
+}
+
+
+// ----- dump: like print, but expands objects/arrays recursively -----
+function replacer(k, v) {
+    var t = typeof v;
+    if (t == "function" || t == "undefined")
+        return "<" + t + ">";
+    if (Array.isArray(this) && t == "object" && v !== null) {  // "safe" mode
+        if (this.indexOf(v) >= 0)
+            return "<VISITED>";
+        this.push(v);
+    }
+    return v;
+}
+
+function obj2str(v) {
+    try {  // can process objects more than once, but throws on cycles
+        return JSON.stringify(v, replacer.bind(null), 2);
+    } catch (e) { // simple safe: exclude visited objects, even if not cyclic
+        return JSON.stringify(v, replacer.bind([]), 2);
+    }
+}
+
+g.dump = function dump() {
+    var toprint = [];
+    for (var i = 0; i < arguments.length; i++) {
+        var v = arguments[i];
+        toprint.push((typeof v == "object") ? obj2str(v) : replacer(0, v));
+    }
+    print.apply(null, toprint);
+}
+
+/**********************************************************************
+ *  main listeners and event loop
+ *********************************************************************/
+mp.keep_running = true;
+g.exit = function() { mp.keep_running = false };  // user-facing too
+mp.register_event("shutdown", g.exit);
+mp.register_event("property-change", notify_observer);
+mp.register_event("hook", run_hook);
+mp.register_event("command-reply", async_command_handler);
+mp.register_event("client-message", dispatch_message);
+mp.register_script_message("key-binding", dispatch_key_binding);
+
+g.mp_event_loop = function mp_event_loop() {
+    var wait = 0;  // seconds
+    do {  // distapch events as long as they arrive, then do the timers/idle
+        var e = mp.wait_event(wait);
+        if (e.event != "none") {
+            dispatch_event(e);
+            wait = 0;  // poll the next one
+        } else {
+            wait = process_timers() / 1000;
+            if (wait != 0 && iobservers.length) {
+                notify_idle_observers();  // can add timers -> recalculate wait
+                wait = peek_timers_wait() / 1000;
+            }
+        }
+    } while (mp.keep_running);
+};
+
+
+// let the user extend us, e.g. by adding items to mp.module_paths
+var initjs = mp.find_config_file("init.js");  // ~~/init.js
+if (initjs)
+    require(initjs.slice(0, -3));  // remove ".js"
+else if ((initjs = mp.find_config_file(".init.js")))
+    mp.msg.warn("Use init.js instead of .init.js (ignoring " + initjs + ")");
+
+})(this)
diff --git a/player/javascript/meson.build b/player/javascript/meson.build
new file mode 100644
index 0000000..bfff4b4
--- /dev/null
+++ b/player/javascript/meson.build
@@ -0,0 +1,6 @@
+defaults_js = custom_target('defaults.js',
+    input: join_paths(source_root, 'player', 'javascript', 'defaults.js'),
+    output: 'defaults.js.inc',
+    command: [file2string, '@INPUT@', '@OUTPUT@'],
+)
+sources += defaults_js