use std::collections::HashMap;
use std::{
    fs,
    path::{Path, PathBuf},
};

use bevy::prelude::*;
use json::JsonValue;

use crate::{json::*, pokemon::*};

pub struct DatabasePlugin;

impl Plugin for DatabasePlugin {
    fn build(&self, app: &mut App) {
        app.insert_resource(Database::<Pokemon>::default())
            .insert_resource(Database::<Nature>::default())
            .insert_resource(Database::<Characteristic>::default())
            .insert_resource(Database::<Ability>::default())
            .add_startup_system(database_setup);
    }
}

#[derive(Resource, Default)]
pub struct Database<T> {
    pub map: HashMap<String, T>,
}

impl<T> Database<T>
where
    T: FromJson + GetKey,
{
    fn populate_from_json(&mut self, json: &JsonValue) {
        for item in json.members() {
            if let Some(item) = T::from_json(item) {
                let key = item.key();
                if !self.map.contains_key(&key) {
                    self.map.insert(key, item);
                }
            }
        }
    }
}

fn database_setup(
    mut pokemon_database: ResMut<Database<Pokemon>>,
    mut ability_database: ResMut<Database<Ability>>,
    mut nature_database: ResMut<Database<Nature>>,
    mut characteristic_database: ResMut<Database<Characteristic>>,
) {
    ability_database.populate_from_json(&read_abilities());
    nature_database.populate_from_json(&read_natures());
    pokemon_database.populate_from_json(&read_pokedex());
    characteristic_database.populate_from_json(&read_characteristics());
}

pub fn load_url_asset(
    url: String,
    path: PathBuf,
    assets: &Res<AssetServer>,
) -> Result<Handle<Image>, Box<dyn std::error::Error>> {
    let system_path = Path::new("assets").join(&path);
    if Path::exists(&system_path) {
        return Ok(assets.load(path));
    }
    let data = reqwest::blocking::get(&url)?.bytes()?;
    fs::write(&system_path, data).unwrap();
    Ok(assets.load(path))
}