use std::io::{Error, ErrorKind};

use crate::{modrinth::{project, versions, Version}, config::Cfg, db::{insert_mod, remove_mod_from_list, get_mod_id, insert_mod_in_list, get_mods, get_mods_from_list}, input::Input, get_current_list};

pub async fn modification(config: Cfg, args: Option<Vec<String>>) -> Result<(), Box<dyn std::error::Error>> {
    
    if args.is_none() { return Err(Box::new(Error::new(ErrorKind::InvalidInput, "TOO_FEW_ARGUMENTS"))) }

    let arguments = Input::from(args.unwrap().join(" "))?;

    if arguments.args.is_none() { return Err(Box::new(Error::new(ErrorKind::InvalidInput, "TOO_FEW_ARGUMENTS"))); };

    match arguments.command.as_str() {
        "add" => {
            add(config, arguments.args.unwrap()).await
        },
        "remove" => {
            remove(config, arguments.args.unwrap())
        },
        _ => Err(Box::new(Error::new(ErrorKind::InvalidInput, "UNKNOWN_SUBCOMMAND")))
    }
}

async fn add(config: Cfg, args: Vec<String>) -> Result<(), Box<dyn std::error::Error>> {
    
    if args.is_empty() { return Err(Box::new(Error::new(ErrorKind::InvalidInput, "TOO_FEW_ARGUMENTS"))); };
    
    let current_list = get_current_list(config.clone())?;

    let project = project(String::from(&config.apis.modrinth), &args[0]).await;

    dbg!(&project);

    if project.versions.is_empty() { panic!("This should never happen"); };

    let available_versions = versions(String::from(&config.apis.modrinth), String::from(&project.id), current_list.clone()).await;

    let current_version = extract_current_version(available_versions.clone())?;
    
    //add to current list and mod table
    match get_mods_from_list(config.clone(), current_list.clone()) {
        Ok(mods) => {
            dbg!(&mods);
            if mods.contains(&project.id) {
                return Err(Box::new(Error::new(ErrorKind::Other, "MOD_ALREADY_ON_LIST"))); } 
            else {
                insert_mod_in_list(config.clone(), current_list.clone(), String::from(&project.id), current_version, available_versions)?;
            } 
        },
        Err(..) => insert_mod_in_list(config.clone(), current_list, String::from(&project.id), current_version, available_versions)?,
    };
    
    match get_mods(config.clone()) {
        Ok(mods) => {
            dbg!(&mods);
            if mods.contains(&project.id) {
                return Err(Box::new(Error::new(ErrorKind::Other, "MOD_ALREADY_IN_DATABASE")))
            } else {
                insert_mod(config.clone(), String::from(&project.id), String::from(&project.title), project.versions)?;
            } 
        },
        Err(..) => insert_mod(config.clone(), String::from(&project.id), String::from(&project.title), project.versions)?,
    };

    Ok(())
}

fn remove(config: Cfg, args: Vec<String>) -> Result<(), Box<dyn std::error::Error>> {
    if args.is_empty() { return Err(Box::new(Error::new(ErrorKind::InvalidInput, "TOO_FEW_ARGUMENTS"))); };

    let current_list = get_current_list(config.clone())?;
    let mod_id = get_mod_id(config.clone(), String::from(&args[0]))?;
    
    //TODO implement remove from modlist if not in any other lists && config clean is true
    match remove_mod_from_list(config, current_list, mod_id) {
        Err(err) => { Err(Box::new(err)) },
        Ok(()) => Ok(()),
    }
}

fn extract_current_version(versions: Vec<Version>) -> Result<String, Box<dyn std::error::Error>> {
    match versions.len() {
        0 => Err(Box::new(Error::new(ErrorKind::NotFound, "NO_VERSIONS_AVAILABLE"))),
        //TODO compare publish dates
        1.. => Ok(versions[0].id.to_string()),
        _ => panic!("available_versions should never be negative"),
    }
}