use mlua::{Function, Lua, Result, Table};
use std::time::{SystemTime, UNIX_EPOCH};

use crate::{
    config::{self, GlobalConfig},
    sheet::{loader::Loader, register::Register},
    state::GlobalState,
};

pub fn neosheet(lua: &Lua) -> Result<()> {
    let exports = lua.create_table()?;

    exports
        .set("sheet", lua.create_userdata(Register)?)
        .unwrap();
    exports
        .set("config", lua.create_userdata(GlobalConfig::default())?)
        .unwrap();
    exports
        .set("state", lua.create_userdata(GlobalState::default())?)
        .unwrap();
    exports
        .set("loader", lua.create_proxy::<Loader>()?)
        .unwrap();

    lua.globals()
        .get::<_, Table>("package")?
        .get::<_, Table>("loaded")?
        .set("neosheet", exports)?;

    Ok(())
}

pub fn math(lua: &Lua) -> Result<()> {
    let math = lua.globals().get::<_, Table>("math");
    let randomseed = math.unwrap().get::<_, Function>("randomseed").unwrap();

    let seed = SystemTime::now()
        .duration_since(UNIX_EPOCH)
        .unwrap()
        .as_millis();
    randomseed.call::<_, ()>(seed).unwrap();
    Ok(())
}

pub fn package(lua: &Lua) -> Result<()> {
    let package = lua.globals().get::<_, Table>("package")?;
    let path = package.get::<_, String>("path")?;
    package.set(
        "path",
        format!(
            "{}/?.lua;{}/?/init.lua;{}/lib/?.lua;{}/lib/?/init.lua;{};./?.lua",
            config::constants::USER_CONFIG_DIR.as_str(),
            config::constants::USER_CONFIG_DIR.as_str(),
            config::constants::USER_CONFIG_DIR.as_str(),
            config::constants::USER_CONFIG_DIR.as_str(),
            path.split(';')
                .filter(|s| s.starts_with('/'))
                .collect::<Vec<&str>>()
                .join(";"),
        ),
    )?;
    Ok(())
}