use crate::{files::{get_downloaded_versions, download_versions, delete_version, disable_version}, db::{userlist_get_all_current_versions_with_mods, lists_get_all_ids, lists_get}, modrinth::get_raw_versions};
use crate::{List, get_current_list, config::Cfg, input::Input};

pub async fn download(config: Cfg, input: Input) -> Result<(), Box<dyn std::error::Error>> {

    let mut liststack: Vec<List> = vec![];
    if input.all_lists {
        let list_ids = lists_get_all_ids(config.clone())?;
        for id in list_ids {
            liststack.push(lists_get(config.clone(), id)?);
        }
    } else {
        let current = get_current_list(config.clone())?;
        println!("Checking for updates of mods in {}", current.id);
        liststack.push(current)
    }

    for current_list in liststack {
        let downloaded_versions = get_downloaded_versions(current_list.clone())?;
        let current_version_ids = userlist_get_all_current_versions_with_mods(config.clone(), String::from(&current_list.id))?;

        let mut to_download: Vec<String> = vec![];
        //(mod_id, version_id)
        let mut to_disable: Vec<(String, String)> = vec![];

        for version in current_version_ids {
            let mod_id = version.0;
            let current_version = version.1;

            let current_download = downloaded_versions.get(&mod_id);

            if current_download.is_none() || input.clean {
                to_download.push(current_version);
            } else {
                let downloaded_version = current_download.ok_or("SOMETHING_HAS_REALLY_GONE_WRONG")?;
                if &current_version != downloaded_version {
                    to_disable.push((mod_id.clone(), String::from(downloaded_version)));
                    to_download.push(current_version);
                }
            }
        }
        
        if input.clean {
            let dl_path = &current_list.download_folder;
            println!("Cleaning {}", dl_path);
            for entry in std::fs::read_dir(dl_path)? {
                let entry = entry?;
                std::fs::remove_file(entry.path())?;
            }
        }

        if !to_download.is_empty() {
            download_versions(current_list.clone(), get_raw_versions(String::from(&config.apis.modrinth), to_download).await).await?;
        } else {
            println!("There are no new versions to download");
        }
        
        if !to_disable.is_empty() {
            for ver in to_disable {
                if input.delete_old {
                    println!("Deleting version {} for mod {}", ver.1, ver.0);
                    delete_version(current_list.clone(), ver.1)?;
                } else { 
                    disable_version(config.clone(), current_list.clone(), ver.1, ver.0)?;
                };
            }
        }
    }

    Ok(())
}