use serde::{Deserialize, Serialize};
use std::fs::File;
use std::io::prelude::*;

use crate::{
    config::Cfg,
    db::{lists_get, lists_get_all_ids, lists_insert, userlist_get_set_version, userlist_get_all_ids, userlist_get_current_version},
    error::MLE,
    mod_add, IDSelector, List, Modloader, AddMod,
};

#[derive(Debug, Serialize, Deserialize)]
struct Export {
    lists: Vec<ExportList>,
}

#[derive(Debug, Serialize, Deserialize)]
struct ExportVersion {
    version: String,
    set: bool
}

impl ExportVersion {
    fn from(config: &Cfg, list_id: &str, mod_id: &str) -> MLE<Self> {
        Ok(Self {
            version: userlist_get_current_version(config, list_id, mod_id)?,
            set: userlist_get_set_version(config, list_id, mod_id)?
        })
    }
}

#[derive(Debug, Serialize, Deserialize)]
struct ExportList {
    id: String,
    versions: Vec<ExportVersion>,
    launcher: String,
    mc_version: String,
    download_folder: Option<String>,
}

impl ExportList {
    pub fn from(config: &Cfg, list_id: String, download: bool) -> MLE<Self> {
        let list = lists_get(config, String::from(&list_id))?;

        let mut dl_folder = None;
        if download {
            dl_folder = Some(list.download_folder)
        };

        let mods = userlist_get_all_ids(config, &list_id)?;
        let mut versions = vec![];
        for m in mods {
            versions.push(ExportVersion::from(config, &list_id, &m)?)
        }

        Ok(Self {
            id: list.id,
            versions,
            launcher: list.modloader.to_string(),
            mc_version: list.mc_version,
            download_folder: dl_folder,
        })
    }
}

pub fn export(config: &Cfg, list: Option<String>) -> MLE<()> {
    let mut list_ids: Vec<String> = vec![];
    if list.is_none() {
        list_ids = lists_get_all_ids(config)?;
    } else {
        list_ids.push(lists_get(config, list.unwrap())?.id);
    }
    let mut lists: Vec<ExportList> = vec![];
    for list_id in list_ids {
        lists.push(ExportList::from(config, list_id, true)?);
    }

    let toml = toml::to_string(&Export { lists })?;

    let filestr = dirs::home_dir().unwrap().join("mlexport.toml");

    let mut file = File::create(filestr.into_os_string().into_string().unwrap().as_str())?;
    file.write_all(toml.as_bytes())?;

    Ok(())
}

pub async fn import(config: &Cfg, file_str: String, direct_download: bool) -> MLE<()> {
    let mut file = File::open(file_str)?;
    let mut content = String::new();
    file.read_to_string(&mut content)?;
    let export: Export = toml::from_str(&content)?;

    for exportlist in export.lists {
        let list = List {
            id: exportlist.id,
            mc_version: exportlist.mc_version,
            modloader: Modloader::from(&exportlist.launcher)?,
            download_folder: exportlist.download_folder.ok_or("NO_DL").unwrap(),
        };
        lists_insert(
            config,
            &list.id,
            &list.mc_version,
            &list.modloader,
            &list.download_folder,
        )?;

        let mut ver_ids = vec![];
        for id in exportlist.versions {
            ver_ids.push(AddMod { id: IDSelector::VersionID(id.version), set_version: id.set} );
        }
        mod_add(config, ver_ids, list, direct_download).await?;
    }
    Ok(())
}