mod models;
mod utils;

use crate::models::config::{Config, Mods, Server};
use crate::models::fabric::FabricVersions;
use crate::{
    models::vanilla::{VanillaVersionDetail, VanillaVersionType, VanillaVersions},
    utils::{with_progressbar, with_spinner},
};
use clap::{
    Parser, Subcommand,
    builder::styling::{self},
};
use dialoguer::{FuzzySelect, Select, theme::ColorfulTheme};
use futures_util::StreamExt;
use sha1::{Digest, Sha1};
use std::error::Error;
use tokio::io::AsyncWriteExt;

fn styles() -> styling::Styles {
    styling::Styles::styled()
        .header(styling::AnsiColor::Green.on_default() | styling::Effects::BOLD)
        .usage(styling::AnsiColor::Green.on_default() | styling::Effects::BOLD)
        .literal(styling::AnsiColor::Cyan.on_default() | styling::Effects::BOLD)
}

#[derive(Parser)]
#[command(name = "mcsm", version, about, styles = styles())]
struct Mcsm {
    #[command(subcommand)]
    command: Commands,
}

#[derive(Subcommand)]
enum Commands {
    Init { name: String },
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    let mcsm = Mcsm::parse();

    match mcsm.command {
        Commands::Init { name: project_name } => {
            tokio::fs::create_dir(&project_name).await?;
            std::env::set_current_dir(&project_name)?;
            let mut config_file = tokio::fs::File::create("mcsm.toml").await?;

            let loaders = vec!["Vanilla", "Fabric"];
            let loader_index = Select::with_theme(&ColorfulTheme::default())
                .with_prompt("Select Loader")
                .items(&loaders)
                .default(0)
                .interact()?;

            match loader_index {
                0 => {
                    const URL: &str =
                        "https://launchermeta.mojang.com/mc/game/version_manifest.json";
                    let res = with_spinner("", "", || async {
                        let res: VanillaVersions = reqwest::get(URL).await?.json().await?;
                        Ok(res)
                    })
                    .await?;

                    let release_versions = res
                        .versions
                        .iter()
                        .filter(|version| version.version_type == VanillaVersionType::Release)
                        .collect::<Vec<_>>();
                    let release_version_names = release_versions
                        .iter()
                        .map(|version| version.id.clone())
                        .collect::<Vec<_>>();

                    let version_index = FuzzySelect::with_theme(&ColorfulTheme::default())
                        .with_prompt("Select Version")
                        .items(&release_version_names)
                        .default(0)
                        .interact()?;

                    let version_detail: VanillaVersionDetail = with_spinner("", "", || async {
                        let version_detail: VanillaVersionDetail =
                            reqwest::get(release_versions[version_index].url.clone())
                                .await?
                                .json()
                                .await?;
                        Ok(version_detail)
                    })
                    .await?;

                    let start_msg = format!(
                        "downloading server.jar for {} {}",
                        loaders[loader_index], release_version_names[version_index]
                    );
                    with_progressbar(
                        &start_msg,
                        "download finished",
                        version_detail.downloads.server.size,
                        |pb| async move {
                            let server_bytes =
                                reqwest::get(version_detail.downloads.server.url).await?;
                            let mut file = tokio::fs::File::create("server.jar").await?;
                            let mut stream = server_bytes.bytes_stream();

                            while let Some(chunk) = stream.next().await {
                                let chunk = chunk?;
                                file.write_all(&chunk).await?;
                                pb.inc(chunk.len() as u64);
                            }
                            Ok(())
                        },
                    )
                    .await?;

                    with_spinner("verifying sha1 hash", "sha1 hash verified", || async {
                        let data = tokio::fs::read("server.jar").await?;
                        let mut hasher = Sha1::new();
                        hasher.update(&data);
                        let hash = hasher.finalize();
                        let hex: String = hash.iter().map(|b| format!("{:02x}", b)).collect();

                        if hex != version_detail.downloads.server.sha1 {
                            tokio::fs::remove_file("server.jar").await?;
                            return Err("sha1 verifaction failed for downloaded file".into());
                        }
                        Ok(())
                    })
                    .await?;

                    let config = Config {
                        server: Server {
                            version: release_version_names[version_index].to_string(),
                            loader: loaders[loader_index].to_string(),
                            loader_version: None,
                        },
                        mods: Mods {},
                    };
                    config_file
                        .write_all(toml::to_string(&config)?.as_bytes())
                        .await?;
                }
                1 => {
                    const URL: &str = "https://meta.fabricmc.net/v2/versions";
                    let res = with_spinner("", "", || async {
                        let res: FabricVersions = reqwest::get(URL).await?.json().await?;
                        Ok(res)
                    })
                    .await?;

                    let game_version_names = res
                        .game
                        .iter()
                        .filter(|game| game.stable)
                        .map(|game| game.version.clone())
                        .collect::<Vec<_>>();

                    let game_version_index = FuzzySelect::with_theme(&ColorfulTheme::default())
                        .with_prompt("Select Game Version")
                        .items(&game_version_names)
                        .default(0)
                        .interact()?;

                    let loader_version_names = res
                        .loader
                        .iter()
                        .filter(|loader| loader.stable)
                        .map(|loader| loader.version.clone())
                        .collect::<Vec<_>>();

                    let loader_version_index = FuzzySelect::with_theme(&ColorfulTheme::default())
                        .with_prompt("Select Loader Version")
                        .items(&loader_version_names)
                        .default(0)
                        .interact()?;

                    let game_version = game_version_names[game_version_index].clone();
                    let loader_version = loader_version_names[loader_version_index].clone();
                    let installer_version = res
                        .installer
                        .iter()
                        .find_map(|installer| {
                            if installer.stable {
                                Some(installer.version.clone())
                            } else {
                                None
                            }
                        })
                        .ok_or("No Installer Version Found")?;

                    let start_msg = format!(
                        "downloading server.jar for {} {}, {}",
                        loaders[loader_index],
                        loader_version_names[loader_version_index],
                        game_version_names[game_version_index],
                    );
                    with_spinner(&start_msg, "download finished", || async {
                        let download_url = format!(
                            "{}/loader/{}/{}/{}/server/jar",
                            URL, game_version, loader_version, installer_version
                        );
                        let res = reqwest::get(download_url).await?;
                        let mut file = tokio::fs::File::create("server.jar").await?;
                        let mut stream = res.bytes_stream();

                        while let Some(chunk) = stream.next().await {
                            file.write_all(&chunk?).await?;
                        }

                        Ok(())
                    })
                    .await?;

                    let config = Config {
                        server: Server {
                            version: game_version,
                            loader: loaders[loader_index].to_string(),
                            loader_version: Some(loader_version),
                        },
                        mods: Mods {},
                    };
                    config_file
                        .write_all(toml::to_string(&config)?.as_bytes())
                        .await?;
                }
                _ => return Err("Invalid selection".into()),
            }
        }
    }

    Ok(())
}