/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "mail-index.h"
#include "mail-storage.h"
#include "mail-search.h"
#include "doveadm-mailbox-list-iter.h"
#include "doveadm-mail-iter.h"
#include "doveadm-mail.h"

struct expunge_cmd_context {
	struct doveadm_mail_cmd_context ctx;
	bool delete_empty_mailbox;
};

static int
cmd_expunge_box(struct doveadm_mail_cmd_context *_ctx,
		const struct mailbox_info *info,
		struct mail_search_args *search_args)
{
	struct expunge_cmd_context *ctx = (struct expunge_cmd_context *)_ctx;
	struct doveadm_mail_iter *iter;
	struct mailbox *box;
	struct mail *mail;
	enum mail_error error;
	int ret = 0;

	if (doveadm_mail_iter_init(_ctx, info, search_args, 0, NULL, 0,
				   &iter) < 0)
		return -1;

	while (doveadm_mail_iter_next(iter, &mail)) {
		if (doveadm_debug) {
			i_debug("expunge: box=%s uid=%u",
				info->vname, mail->uid);
		}
		mail_expunge(mail);
	}

	if (doveadm_mail_iter_deinit_keep_box(&iter, &box) < 0)
		ret = -1;
	else if (mailbox_sync(box, 0) < 0) {
		i_error("Syncing mailbox '%s' failed: %s",
			mailbox_get_vname(box),
			mailbox_get_last_internal_error(box, NULL));
		doveadm_mail_failed_mailbox(_ctx, box);
		ret = -1;
	}

	if (ctx->delete_empty_mailbox && ret == 0) {
		if (mailbox_delete_empty(box) < 0) {
			error = mailbox_get_last_mail_error(box);
			if (error != MAIL_ERROR_EXISTS) {
				i_error("Deleting mailbox '%s' failed: %s",
					mailbox_get_vname(box),
					mailbox_get_last_internal_error(box, NULL));
				doveadm_mail_failed_mailbox(_ctx, box);
				ret = -1;
			}
		} else {
			if (mailbox_set_subscribed(box, FALSE) < 0) {
				i_error("Unsubscribing mailbox '%s' failed: %s",
					mailbox_get_vname(box),
					mailbox_get_last_internal_error(box, NULL));
				doveadm_mail_failed_mailbox(_ctx, box);
				ret = -1;
			}
		}
	}
	mailbox_free(&box);
	return ret;
}

static bool
expunge_search_args_is_mailbox_ok(struct mail_search_arg *args);

static bool
expunge_search_args_is_mailbox_or_ok(struct mail_search_arg *args)
{
	struct mail_search_arg *arg;

	for (arg = args; arg != NULL; arg = arg->next) {
		switch (arg->type) {
		case SEARCH_OR:
			if (!expunge_search_args_is_mailbox_or_ok(arg->value.subargs))
				return FALSE;
			break;
		case SEARCH_SUB:
		case SEARCH_INTHREAD:
			if (!expunge_search_args_is_mailbox_ok(arg->value.subargs))
				return FALSE;
			break;
		case SEARCH_MAILBOX:
		case SEARCH_MAILBOX_GUID:
		case SEARCH_MAILBOX_GLOB:
			break;
		default:
			return FALSE;
		}
	}
	return TRUE;
}

static bool
expunge_search_args_is_mailbox_ok(struct mail_search_arg *args)
{
	struct mail_search_arg *arg;
	bool have_or = FALSE;

	/* a) we find one mailbox here in the SUB block */
	for (arg = args; arg != NULL; arg = arg->next) {
		switch (arg->type) {
		case SEARCH_MAILBOX:
		case SEARCH_MAILBOX_GUID:
		case SEARCH_MAILBOX_GLOB:
			return TRUE;
		case SEARCH_OR:
			have_or = TRUE;
			break;
		case SEARCH_SUB:
		case SEARCH_INTHREAD:
			if (expunge_search_args_is_mailbox_ok(arg->value.subargs))
				return TRUE;
			break;
		default:
			break;
		}
	}

	/* b) there is at least one OR block, and all of the ORs must have
	   mailbox */
	if (!have_or)
		return FALSE;

	for (arg = args; arg != NULL; arg = arg->next) {
		if (arg->type == SEARCH_OR &&
		    !expunge_search_args_is_mailbox_or_ok(arg->value.subargs))
			return FALSE;
	}
	return TRUE;
}

static bool
expunge_search_args_is_msgset_ok(struct mail_search_arg *args);

static bool
expunge_search_args_is_msgset_or_ok(struct mail_search_arg *args)
{
	struct mail_search_arg *arg;

	/* we're done if all OR branches contain something else besides
	   MAILBOXes */
	for (arg = args; arg != NULL; arg = arg->next) {
		switch (arg->type) {
		case SEARCH_MAILBOX:
		case SEARCH_MAILBOX_GUID:
		case SEARCH_MAILBOX_GLOB:
			return FALSE;
		case SEARCH_OR:
			if (!expunge_search_args_is_msgset_or_ok(arg->value.subargs))
				return FALSE;
			break;
		case SEARCH_SUB:
			if (!expunge_search_args_is_msgset_ok(arg->value.subargs))
				return FALSE;
			break;
		default:
			break;
		}
	}
	return TRUE;
}

static bool
expunge_search_args_is_msgset_ok(struct mail_search_arg *args)
{
	struct mail_search_arg *arg;

	/* all args can't be just MAILBOXes */
	for (arg = args; arg != NULL; arg = arg->next) {
		switch (arg->type) {
		case SEARCH_MAILBOX:
		case SEARCH_MAILBOX_GUID:
		case SEARCH_MAILBOX_GLOB:
			break;
		case SEARCH_OR:
			/* if each OR branch has something else than just
			   MAILBOXes, we're ok */
			if (expunge_search_args_is_msgset_or_ok(arg->value.subargs))
				return TRUE;
			break;
		case SEARCH_SUB:
			if (expunge_search_args_is_msgset_ok(arg->value.subargs))
				return TRUE;
			break;
		default:
			return TRUE;
		}
	}
	return FALSE;
}

static int
cmd_expunge_run(struct doveadm_mail_cmd_context *ctx, struct mail_user *user)
{
	const enum mailbox_list_iter_flags iter_flags =
		MAILBOX_LIST_ITER_NO_AUTO_BOXES |
		MAILBOX_LIST_ITER_RETURN_NO_FLAGS;
	struct doveadm_mailbox_list_iter *iter;
	const struct mailbox_info *info;
	int ret = 0;

	iter = doveadm_mailbox_list_iter_init(ctx, user, ctx->search_args,
					      iter_flags);
	while ((info = doveadm_mailbox_list_iter_next(iter)) != NULL) T_BEGIN {
		if (cmd_expunge_box(ctx, info, ctx->search_args) < 0)
			ret = -1;
	} T_END;
	if (doveadm_mailbox_list_iter_deinit(&iter) < 0)
		ret = -1;
	return ret;
}

void expunge_search_args_check(struct mail_search_args *args, const char *cmd)
{
	if (!expunge_search_args_is_mailbox_ok(args->args)) {
		i_fatal_status(EX_USAGE,
			"%s: To avoid accidents, search query "
			"must contain MAILBOX in all search branches", cmd);
	}
	if (!expunge_search_args_is_msgset_ok(args->args)) {
		i_fatal_status(EX_USAGE,
			"%s: To avoid accidents, each branch in search query "
			"must contain something else besides MAILBOX "
			"(e.g. just add \"all\" if you want everything)", cmd);
	}
	mail_search_args_simplify(args);
}

static void cmd_expunge_init(struct doveadm_mail_cmd_context *ctx,
			     const char *const args[])
{
	if (args[0] == NULL)
		doveadm_mail_help_name("expunge");

	ctx->search_args = doveadm_mail_build_search_args(args);
	expunge_search_args_check(ctx->search_args, "expunge");
}

static bool cmd_expunge_parse_arg(struct doveadm_mail_cmd_context *_ctx, int c)
{
	struct expunge_cmd_context *ctx = (struct expunge_cmd_context *)_ctx;

	switch (c) {
	case 'd':
		ctx->delete_empty_mailbox = TRUE;
		break;
	default:
		return FALSE;
	}
	return TRUE;
}

static struct doveadm_mail_cmd_context *cmd_expunge_alloc(void)
{
	struct expunge_cmd_context *ctx;

	ctx = doveadm_mail_cmd_alloc(struct expunge_cmd_context);
	ctx->ctx.getopt_args = "d";
	ctx->ctx.v.parse_arg = cmd_expunge_parse_arg;
	ctx->ctx.v.init = cmd_expunge_init;
	ctx->ctx.v.run = cmd_expunge_run;
	return &ctx->ctx;
}

struct doveadm_cmd_ver2 doveadm_cmd_expunge_ver2 = {
	.name = "expunge",
	.mail_cmd = cmd_expunge_alloc,
	.usage = DOVEADM_CMD_MAIL_USAGE_PREFIX "[-m] <search query>",
DOVEADM_CMD_PARAMS_START
DOVEADM_CMD_MAIL_COMMON
DOVEADM_CMD_PARAM('d', "delete-empty-mailbox", CMD_PARAM_BOOL, 0)
DOVEADM_CMD_PARAM('\0', "query", CMD_PARAM_ARRAY, CMD_PARAM_FLAG_POSITIONAL)
DOVEADM_CMD_PARAMS_END
};