/*
 * This file is part of sdbclient
 * Copyright (C) 2022 Jonni Liljamo <jonni@liljamo.com>
 *
 * Licensed under GPL-3.0-only.
 * See LICENSE for licensing information.
 */

use std::sync::Mutex;

use bevy_mod_scripting::prelude::*;

use bevy::prelude::*;
use bevy_console::PrintConsoleLine;

pub struct LuaPlugin;

impl Plugin for LuaPlugin {
    fn build(&self, app: &mut App) {
        app.add_startup_system(load_scripts)
            .add_script_host::<LuaScriptHost<()>, _>(CoreStage::PostUpdate)
            .add_script_handler_stage::<LuaScriptHost<()>, _, 0, 0>(CoreStage::PostUpdate)
            .add_api_provider::<LuaScriptHost<()>>(Box::new(LuaAPIProvider))
            .add_api_provider::<LuaScriptHost<()>>(Box::new(LuaBevyAPIProvider));
    }
}

fn load_scripts(asset_server: Res<AssetServer>, mut commands: Commands) {
    let script_paths = vec!["ui_play.lua"];
    let mut scripts = vec![];

    for path in script_paths {
        let handle = asset_server.load::<LuaFile, &str>(&format!("scripts/{}", path));
        scripts.push(Script::<LuaFile>::new(path.to_string(), handle));
    }

    commands
        .spawn(())
        .insert(ScriptCollection::<LuaFile> { scripts });
}

pub struct LuaAPIProvider;

impl APIProvider for LuaAPIProvider {
    type APITarget = Mutex<Lua>;
    type DocTarget = LuaDocFragment;
    type ScriptContext = Mutex<Lua>;

    fn attach_api(&mut self, api: &mut Self::APITarget) -> Result<(), ScriptError> {
        let api = api.get_mut().unwrap();

        api.globals()
            .set(
                "print_to_console",
                api.create_function(|ctx, msg: String| {
                    // retrieve the world pointer
                    let world = ctx.get_world()?;
                    let mut world = world.write();

                    let mut events: Mut<Events<PrintConsoleLine>> =
                        world.get_resource_mut().unwrap();
                    events.send(PrintConsoleLine::new(msg.into()));

                    Ok(())
                })
                .map_err(ScriptError::new_other)?,
            )
            .map_err(ScriptError::new_other)?;

        api.globals()
            .set(
                "print",
                api.create_function(|_ctx, msg: String| {
                    info!("{}", msg);
                    Ok(())
                })
                .map_err(ScriptError::new_other)?,
            )
            .map_err(ScriptError::new_other)?;

        Ok(())
    }
}