/*
 * database.c
 * vim: expandtab:ts=4:sts=4:sw=4
 *
 * Copyright (C) 2020 Michael Vetter <jubalh@idoru.org>
 *
 * This file is part of Profanity.
 *
 * Profanity is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Profanity 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Profanity.  If not, see <https://www.gnu.org/licenses/>.
 *
 * In addition, as a special exception, the copyright holders give permission to
 * link the code of portions of this program with the OpenSSL library under
 * certain conditions as described in each individual source file, and
 * distribute linked combinations including the two.
 *
 * You must obey the GNU General Public License in all respects for all of the
 * code used other than OpenSSL. If you modify file(s) with this exception, you
 * may extend this exception to your version of the file(s), but you are not
 * obligated to do so. If you do not wish to do so, delete this exception
 * statement from your version. If you delete this exception statement from all
 * source files in the program, then also delete it here.
 *
 */

#define _GNU_SOURCE 1

#include <sys/stat.h>
#include <sqlite3.h>
#include <glib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include "log.h"
#include "common.h"
#include "config/files.h"

static sqlite3* g_chatlog_database;

static void _add_to_db(ProfMessage* message, char* type, const Jid* const from_jid, const Jid* const to_jid);
static char* _get_db_filename(ProfAccount* account);
static prof_msg_type_t _get_message_type_type(const char* const type);

static char*
_get_db_filename(ProfAccount* account)
{
    gchar* database_dir = files_get_account_data_path(DIR_DATABASE, account->jid);

    int res = g_mkdir_with_parents(database_dir, S_IRWXU);
    if (res == -1) {
        char* errmsg = strerror(errno);
        if (errmsg) {
            log_error("DATABASE: error creating directory: %s, %s", database_dir, errmsg);
        } else {
            log_error("DATABASE: creating directory: %s", database_dir);
        }
        g_free(database_dir);
        return NULL;
    }

    GString* chatlog_filename = g_string_new(database_dir);
    g_string_append(chatlog_filename, "/chatlog.db");
    gchar* result = g_strdup(chatlog_filename->str);
    g_string_free(chatlog_filename, TRUE);
    g_free(database_dir);

    return result;
}

gboolean
log_database_init(ProfAccount* account)
{
    int ret = sqlite3_initialize();
    if (ret != SQLITE_OK) {
        log_error("Error initializing SQLite database: %d", ret);
        return FALSE;
    }

    char* filename = _get_db_filename(account);
    if (!filename) {
        return FALSE;
    }

    ret = sqlite3_open(filename, &g_chatlog_database);
    if (ret != SQLITE_OK) {
        const char* err_msg = sqlite3_errmsg(g_chatlog_database);
        log_error("Error opening SQLite database: %s", err_msg);
        free(filename);
        return FALSE;
    }

    char* err_msg;
    // id is the ID of DB the entry
    // from_jid is the senders jid
    // to_jid is the receivers jid
    // from_resource is the senders resource
    // to_jid is the receivers resource
    // message is the message text
    // timestamp the timestamp like "2020/03/24 11:12:14"
    // type is there to distinguish: message (chat), MUC message (muc), muc pm (mucpm)
    // stanza_id is the ID in <message>
    // archive_id is the stanza-id from from XEP-0359: Unique and Stable Stanza IDs used for XEP-0313: Message Archive Management
    // replace_id is the ID from XEP-0308: Last Message Correction
    // encryption is to distinguish: none, omemo, otr, pgp
    // marked_read is 0/1 whether a message has been marked as read via XEP-0333: Chat Markers
    char* query = "CREATE TABLE IF NOT EXISTS `ChatLogs` ( `id` INTEGER PRIMARY KEY AUTOINCREMENT, `from_jid` TEXT NOT NULL, `to_jid` TEXT NOT NULL, `from_resource` TEXT, `to_resource` TEXT, `message` TEXT, `timestamp` TEXT, `type` TEXT, `stanza_id` TEXT, `archive_id` TEXT, `replace_id` TEXT, `encryption` TEXT, `marked_read` INTEGER)";
    if (SQLITE_OK != sqlite3_exec(g_chatlog_database, query, NULL, 0, &err_msg)) {
        goto out;
    }

    query = "CREATE TABLE IF NOT EXISTS `DbVersion` ( `dv_id` INTEGER PRIMARY KEY, `version` INTEGER UNIQUE)";
    if (SQLITE_OK != sqlite3_exec(g_chatlog_database, query, NULL, 0, &err_msg)) {
        goto out;
    }

    query = "INSERT OR IGNORE INTO `DbVersion` (`version`) VALUES('1')";
    if (SQLITE_OK != sqlite3_exec(g_chatlog_database, query, NULL, 0, &err_msg)) {
        goto out;
    }

    log_debug("Initialized SQLite database: %s", filename);
    free(filename);
    return TRUE;

out:
    if (err_msg) {
        log_error("SQLite error: %s", err_msg);
        sqlite3_free(err_msg);
    } else {
        log_error("Unknown SQLite error");
    }
    free(filename);
    return FALSE;
}

void
log_database_close(void)
{
    if (g_chatlog_database) {
        sqlite3_close(g_chatlog_database);
        sqlite3_shutdown();
        g_chatlog_database = NULL;
    }
}

void
log_database_add_incoming(ProfMessage* message)
{
    if (message->to_jid) {
        _add_to_db(message, NULL, message->from_jid, message->to_jid);
    } else {
        const char* jid = connection_get_fulljid();
        Jid* myjid = jid_create(jid);

        _add_to_db(message, NULL, message->from_jid, myjid);

        jid_destroy(myjid);
    }
}

static void
_log_database_add_outgoing(char* type, const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
{
    ProfMessage* msg = message_init();

    msg->id = id ? strdup(id) : NULL;
    msg->from_jid = jid_create(barejid);
    msg->plain = message ? strdup(message) : NULL;
    msg->replace_id = replace_id ? strdup(replace_id) : NULL;
    msg->timestamp = g_date_time_new_now_local(); //TODO: get from outside. best to have whole ProfMessage from outside
    msg->enc = enc;

    const char* jid = connection_get_fulljid();
    Jid* myjid = jid_create(jid);

    _add_to_db(msg, type, myjid, msg->from_jid); // TODO: myjid now in profmessage

    jid_destroy(myjid);
    message_free(msg);
}

void
log_database_add_outgoing_chat(const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
{
    _log_database_add_outgoing("chat", id, barejid, message, replace_id, enc);
}

void
log_database_add_outgoing_muc(const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
{
    _log_database_add_outgoing("muc", id, barejid, message, replace_id, enc);
}

void
log_database_add_outgoing_muc_pm(const char* const id, const char* const barejid, const char* const message, const char* const replace_id, prof_enc_t enc)
{
    _log_database_add_outgoing("mucpm", id, barejid, message, replace_id, enc);
}

GSList*
log_database_get_previous_chat(const gchar* const contact_barejid)
{
    sqlite3_stmt* stmt = NULL;
    char* query;
    const char* jid = connection_get_fulljid();
    Jid* myjid = jid_create(jid);

    if (asprintf(&query, "SELECT * FROM (SELECT `message`, `timestamp`, `from_jid`, `type` from `ChatLogs` WHERE (`from_jid` = '%s' AND `to_jid` = '%s') OR (`from_jid` = '%s' AND `to_jid` = '%s') ORDER BY `timestamp` DESC LIMIT 10) ORDER BY `timestamp` ASC;", contact_barejid, myjid->barejid, myjid->barejid, contact_barejid) == -1) {
        log_error("log_database_get_previous_chat(): SQL query. could not allocate memory");
        return NULL;
    }

    jid_destroy(myjid);

    int rc = sqlite3_prepare_v2(g_chatlog_database, query, -1, &stmt, NULL);
    if (rc != SQLITE_OK) {
        log_error("log_database_get_previous_chat(): unknown SQLite error");
        return NULL;
    }

    GSList* history = NULL;

    while (sqlite3_step(stmt) == SQLITE_ROW) {
        // TODO: also save to jid. since now part of profmessage
        char* message = (char*)sqlite3_column_text(stmt, 0);
        char* date = (char*)sqlite3_column_text(stmt, 1);
        char* from = (char*)sqlite3_column_text(stmt, 2);
        char* type = (char*)sqlite3_column_text(stmt, 3);

        ProfMessage* msg = message_init();
        msg->from_jid = jid_create(from);
        msg->plain = strdup(message);
        msg->timestamp = g_date_time_new_from_iso8601(date, NULL);
        msg->type = _get_message_type_type(type);
        // TODO: later we can get more fields like 'enc'. then we can display the history like regular chats with all info the user enabled.

        history = g_slist_append(history, msg);
    }
    sqlite3_finalize(stmt);
    free(query);

    return history;
}

static const char*
_get_message_type_str(prof_msg_type_t type)
{
    switch (type) {
    case PROF_MSG_TYPE_CHAT:
        return "chat";
    case PROF_MSG_TYPE_MUC:
        return "muc";
    case PROF_MSG_TYPE_MUCPM:
        return "mucpm";
    case PROF_MSG_TYPE_UNINITIALIZED:
        return NULL;
    }
    return NULL;
}

static prof_msg_type_t
_get_message_type_type(const char* const type)
{
    if (g_strcmp0(type, "chat") == 0) {
        return PROF_MSG_TYPE_CHAT;
    } else if (g_strcmp0(type, "muc") == 0) {
        return PROF_MSG_TYPE_MUC;
    } else if (g_strcmp0(type, "mucpm") == 0) {
        return PROF_MSG_TYPE_MUCPM;
    } else {
        return PROF_MSG_TYPE_UNINITIALIZED;
    }
}

static const char*
_get_message_enc_str(prof_enc_t enc)
{
    switch (enc) {
    case PROF_MSG_ENC_OX:
        return "ox";
    case PROF_MSG_ENC_PGP:
        return "pgp";
    case PROF_MSG_ENC_OTR:
        return "otr";
    case PROF_MSG_ENC_OMEMO:
        return "omemo";
    case PROF_MSG_ENC_NONE:
        return "none";
    }

    return "none"; // do not return none - return NULL
}

static void
_add_to_db(ProfMessage* message, char* type, const Jid* const from_jid, const Jid* const to_jid)
{
    if (!g_chatlog_database) {
        log_debug("log_database_add() called but db is not initialized");
        return;
    }

    char* err_msg;
    char* query;
    gchar* date_fmt;

    if (message->timestamp) {
        date_fmt = g_date_time_format_iso8601(message->timestamp);
    } else {
        date_fmt = g_date_time_format_iso8601(g_date_time_new_now_local());
    }

    const char* enc = _get_message_enc_str(message->enc);

    if (!type) {
        type = (char*)_get_message_type_str(message->type);
    }

    char* escaped_message = str_replace(message->plain, "'", "''");

    if (asprintf(&query, "INSERT INTO `ChatLogs` (`from_jid`, `from_resource`, `to_jid`, `to_resource`, `message`, `timestamp`, `stanza_id`, `archive_id`, `replace_id`, `type`, `encryption`) SELECT '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s' WHERE NOT EXISTS (SELECT 1 FROM `ChatLogs` WHERE `archive_id` = '%s')",
                 from_jid->barejid,
                 from_jid->resourcepart ? from_jid->resourcepart : "",
                 to_jid->barejid,
                 to_jid->resourcepart ? to_jid->resourcepart : "",
                 escaped_message,
                 date_fmt,
                 message->id ? message->id : "",
                 message->stanzaid ? message->stanzaid : "",
                 message->replace_id ? message->replace_id : "",
                 type,
                 enc,
                 message->stanzaid)
        == -1) {
        log_error("log_database_add(): SQL query. could not allocate memory");
        return;
    }
    free(escaped_message);
    g_free(date_fmt);

    if (SQLITE_OK != sqlite3_exec(g_chatlog_database, query, NULL, 0, &err_msg)) {
        if (err_msg) {
            log_error("SQLite error: %s", err_msg);
            sqlite3_free(err_msg);
        } else {
            log_error("Unknown SQLite error");
        }
    }
    free(query);
}