/* Copyright (c) 2002-2018 Pigeonhole authors, see the included COPYING file
 */

#include "lib.h"
#include "mail-storage.h"

#include "sieve-common.h"
#include "sieve-code.h"
#include "sieve-message.h"
#include "sieve-commands.h"
#include "sieve-validator.h"
#include "sieve-generator.h"
#include "sieve-interpreter.h"
#include "sieve-dump.h"

/*
 * Size test
 *
 * Syntax:
 *    size <":over" / ":under"> <limit: number>
 */

static bool
tst_size_registered(struct sieve_validator *valdtr,
		    const struct sieve_extension *ext,
		    struct sieve_command_registration *cmd_reg);
static bool
tst_size_pre_validate(struct sieve_validator *valdtr,
		      struct sieve_command *tst);
static bool
tst_size_validate(struct sieve_validator *valdtr, struct sieve_command *tst);
static bool
tst_size_generate(const struct sieve_codegen_env *cgenv,
		  struct sieve_command *ctx);

const struct sieve_command_def tst_size = {
	.identifier = "size",
	.type = SCT_TEST,
	.positional_args = 1,
	.subtests = 0,
	.block_allowed = FALSE,
	.block_required = FALSE,
	.registered = tst_size_registered,
	.pre_validate = tst_size_pre_validate,
	.validate = tst_size_validate,
	.generate = tst_size_generate
};

/*
 * Size operations
 */

static bool
tst_size_operation_dump(const struct sieve_dumptime_env *denv,
			sieve_size_t *address);
static int
tst_size_operation_execute(const struct sieve_runtime_env *renv,
			   sieve_size_t *address);

const struct sieve_operation_def tst_size_over_operation = {
	.mnemonic = "SIZE-OVER",
	.code = SIEVE_OPERATION_SIZE_OVER,
	.dump = tst_size_operation_dump,
	.execute = tst_size_operation_execute
};

const struct sieve_operation_def tst_size_under_operation = {
	.mnemonic = "SIZE-UNDER",
	.code = SIEVE_OPERATION_SIZE_UNDER,
	.dump = tst_size_operation_dump,
	.execute = tst_size_operation_execute
};

/*
 * Context data
 */

struct tst_size_context_data {
	enum { SIZE_UNASSIGNED, SIZE_UNDER, SIZE_OVER } type;
};

#define TST_SIZE_ERROR_DUP_TAG \
	"exactly one of the ':under' or ':over' tags must be specified " \
	"for the size test, but more were found"

/*
 * Tag validation
 */

static bool
tst_size_validate_over_tag(struct sieve_validator *valdtr,
			   struct sieve_ast_argument **arg,
			   struct sieve_command *tst)
{
	struct tst_size_context_data *ctx_data =
		(struct tst_size_context_data *)tst->data;

	if (ctx_data->type != SIZE_UNASSIGNED) {
		sieve_argument_validate_error(valdtr, *arg,
					      TST_SIZE_ERROR_DUP_TAG);
		return FALSE;
	}

	ctx_data->type = SIZE_OVER;

	/* Delete this tag */
	*arg = sieve_ast_arguments_detach(*arg, 1);

	return TRUE;
}

static bool
tst_size_validate_under_tag(struct sieve_validator *valdtr,
			    struct sieve_ast_argument **arg ATTR_UNUSED,
			    struct sieve_command *tst)
{
	struct tst_size_context_data *ctx_data =
		(struct tst_size_context_data *)tst->data;

	if (ctx_data->type != SIZE_UNASSIGNED) {
		sieve_argument_validate_error(valdtr, *arg,
					      TST_SIZE_ERROR_DUP_TAG);
		return FALSE;
	}

	ctx_data->type = SIZE_UNDER;

	/* Delete this tag */
	*arg = sieve_ast_arguments_detach(*arg, 1);

	return TRUE;
}

/*
 * Test registration
 */

static const struct sieve_argument_def size_over_tag = {
	.identifier = "over",
	.validate = tst_size_validate_over_tag
};

static const struct sieve_argument_def size_under_tag = {
	.identifier = "under",
	.validate = tst_size_validate_under_tag,
};

static bool
tst_size_registered(struct sieve_validator *valdtr,
		    const struct sieve_extension *ext ATTR_UNUSED,
		    struct sieve_command_registration *cmd_reg)
{
	/* Register our tags */
	sieve_validator_register_tag(valdtr, cmd_reg, NULL, &size_over_tag, 0);
	sieve_validator_register_tag(valdtr, cmd_reg, NULL, &size_under_tag, 0);

	return TRUE;
}

/*
 * Test validation
 */

static bool
tst_size_pre_validate(struct sieve_validator *valdtr ATTR_UNUSED,
		      struct sieve_command *tst)
{
	struct tst_size_context_data *ctx_data;

	/* Assign context */
	ctx_data = p_new(sieve_command_pool(tst),
			 struct tst_size_context_data, 1);
	ctx_data->type = SIZE_UNASSIGNED;
	tst->data = ctx_data;

	return TRUE;
}

static bool
tst_size_validate(struct sieve_validator *valdtr, struct sieve_command *tst)
{
	struct tst_size_context_data *ctx_data =
		(struct tst_size_context_data *)tst->data;
	struct sieve_ast_argument *arg = tst->first_positional;

	if (ctx_data->type == SIZE_UNASSIGNED) {
		sieve_command_validate_error(valdtr, tst,
			"the size test requires either the :under or the :over tag "
			"to be specified");
		return FALSE;
	}

	if (!sieve_validate_positional_argument(valdtr, tst, arg, "limit", 1,
						SAAT_NUMBER))
		return FALSE;

	return sieve_validator_argument_activate(valdtr, tst, arg, FALSE);
}

/*
 * Code generation
 */

bool tst_size_generate(const struct sieve_codegen_env *cgenv,
		       struct sieve_command *tst)
{
	struct tst_size_context_data *ctx_data =
		(struct tst_size_context_data *)tst->data;

	if (ctx_data->type == SIZE_OVER) {
		sieve_operation_emit(cgenv->sblock, NULL,
				     &tst_size_over_operation);
	} else {
		sieve_operation_emit(cgenv->sblock, NULL,
				     &tst_size_under_operation);
	}

 	/* Generate arguments */
	if (!sieve_generate_arguments(cgenv, tst, NULL))
		return FALSE;

	return TRUE;
}

/*
 * Code dump
 */

static bool
tst_size_operation_dump(const struct sieve_dumptime_env *denv,
			sieve_size_t *address)
{
	sieve_code_dumpf(denv, "%s", sieve_operation_mnemonic(denv->oprtn));
	sieve_code_descend(denv);

	return sieve_opr_number_dump(denv, address, "limit");
}

/*
 * Code execution
 */

static inline bool
tst_size_get(const struct sieve_runtime_env *renv, sieve_number_t *size)
{
	struct mail *mail = sieve_message_get_mail(renv->msgctx);
	uoff_t psize;

	if (mail_get_physical_size(mail, &psize) < 0)
		return FALSE;

	*size = psize;
	return TRUE;
}

static int
tst_size_operation_execute(const struct sieve_runtime_env *renv,
			   sieve_size_t *address)
{
	sieve_number_t mail_size, limit;
	int ret;

	/*
	 * Read operands
	 */

	/* Read size limit */
	if ((ret = sieve_opr_number_read(renv, address, "limit", &limit)) <= 0)
		return ret;

	/*
	 * Perform test
	 */

	/* Get the size of the message */
	if (!tst_size_get(renv, &mail_size)) {
		/* FIXME: improve this error */
		e_error(renv->event, "failed to assess message size");
		return SIEVE_EXEC_FAILURE;
	}

	/* Perform the test */
	if (sieve_operation_is(renv->oprtn, tst_size_over_operation)) {
		sieve_runtime_trace(renv, SIEVE_TRLVL_TESTS, "size :over test");

		if (sieve_runtime_trace_active(renv, SIEVE_TRLVL_MATCHING)) {
			sieve_runtime_trace_descend(renv);

			sieve_runtime_trace(
				renv, 0, "comparing message size %llu",
				(unsigned long long)mail_size);
			sieve_runtime_trace(
				renv, 0, "with upper limit %llu",
				(unsigned long long)limit);
		}

		sieve_interpreter_set_test_result(renv->interp,
						  (mail_size > limit));
	} else {
		sieve_runtime_trace(renv, SIEVE_TRLVL_TESTS,
				    "size :under test");

		if (sieve_runtime_trace_active(renv, SIEVE_TRLVL_MATCHING)) {
			sieve_runtime_trace_descend(renv);

			sieve_runtime_trace(
				renv, 0, "comparing message size %llu",
				(unsigned long long)mail_size);
			sieve_runtime_trace(
				renv, 0, "with lower limit %llu",
				(unsigned long long)limit);
		}

		sieve_interpreter_set_test_result(renv->interp,
						  (mail_size < limit));
	}
	return SIEVE_EXEC_OK;
}