mod cli;

use std::error::Error;
use std::path::Path;
use std::process::ExitCode;
use log::{error, info, trace, LevelFilter};
use clap::Parser;
use ozone::launcher::{Instance, JavaRuntimeSetting, Launcher, Settings};
use ozone::launcher::version::{VersionList, VersionResult};
use uuid::Uuid;
use ozone::auth::{Account, AuthenticationDatabase};
use crate::cli::{Cli, InstanceCommand, RootCommand};

fn find_account<'a>(auth: &'a AuthenticationDatabase, input: &str) -> Vec<&'a Account> {
    if let Ok(uuid) = input.parse::<Uuid>() {
        todo!()
    }

    let input = input.to_ascii_lowercase();

    auth.users.iter().filter(|a| match *a {
        Account::Dummy(profile) => profile.name.to_ascii_lowercase().starts_with(&input),
        Account::MSA(account) =>
            account.player_profile.as_ref().is_some_and(|p| p.name.to_ascii_lowercase().starts_with(&input)) ||
            account.gamertag.as_ref().is_some_and(|p| p.to_ascii_lowercase().starts_with(&input))
    }).collect()
}

fn display_instance(instance: &Instance, id: Uuid, home: impl AsRef<Path>, selected: bool, verbose: bool) {
    println!("Instance `{}':{}", instance.name, if selected { " (selected)" } else { "" });
    println!("  UUID: {}", id);
    println!("  Version: {}", instance.game_version);
    println!("  Location: {}", home.as_ref().join(Settings::get_instance_path(id)).display());

    if !verbose { return; }

    if let Some(ref args) = instance.jvm_arguments {
        println!("  JVM arguments: <{} argument{}>", args.len(), if args.len() == 1 { "" } else { "s" })
    }

    if let Some(res) = instance.resolution {
        println!("  Resolution: {}x{}", res.width, res.height);
    }

    match &instance.java_runtime {
        Some(JavaRuntimeSetting::Component(c)) => println!("  Java runtime component: {c}"),
        Some(JavaRuntimeSetting::Path(p)) => println!("  Java runtime path: {}", p.display()),
        _ => ()
    }
}

async fn main_inner(cli: Cli) -> Result<ExitCode, Box<dyn Error>> {
    let Some(home) = cli.home.or_else(Launcher::sensible_home) else {
        error!("Could not choose a launcher home directory. Please choose one with `--home'.");
        return Ok(ExitCode::FAILURE); // we print our own error message
    };

    trace!("Sensible home could be {home:?}");
    let mut settings = Settings::load(home.join("ozone.json")).await?;

    match &cli.subcmd {
        RootCommand::Instance(p) => match p.command() {
            InstanceCommand::List => {
                let mut first = true;

                if settings.instances.is_empty() {
                    eprintln!("There are no instances. Create one with `profile create <name>'.");
                    return Ok(ExitCode::SUCCESS);
                }

                for (cur_id, instance) in settings.instances.iter() {
                    if !first {
                        println!();
                    }

                    first = false;

                    let cur_id = *cur_id;
                    let sel = settings.selected_instance.is_some_and(|id| id == cur_id);
                    display_instance(instance, cur_id, &home, sel, false);
                }
            },
            InstanceCommand::Create(args) => {
                if args.name.is_empty() {
                    eprintln!("The instance must not have an empty name.");
                    return Ok(ExitCode::FAILURE);
                }

                let mut inst = if args.clone {
                    if let Some(selected_inst) = settings.get_selected_instance() {
                        let mut inst = selected_inst.clone();
                        inst.name.replace_range(.., &args.name);
                        inst
                    } else {
                        eprintln!("You do not have an instance selected.");
                        return Ok(ExitCode::FAILURE);
                    }
                } else {
                    Instance::new(&args.name)
                };

                if let Some(ref ver_name) = args.settings.version {
                    // FIXME: don't hardcode "versions" path
                    let versions = VersionList::new(home.join("versions"), !cli.offline).await?;
                    if matches!(versions.get_version_lazy(ver_name), VersionResult::None) {
                        eprintln!("The version `{}' could not be found.", ver_name);
                        return Ok(ExitCode::FAILURE);
                    }
                }
                
                args.settings.apply_to(&mut inst);

                let new_id = Uuid::new_v4();
                settings.instances.insert(new_id, inst);
                
                if !args.no_select {
                    settings.selected_instance = Some(new_id);
                }

                settings.save().await?;
            },
            InstanceCommand::Select(args) => {
                if let Ok(uuid) = args.instance.parse::<Uuid>() {
                    if !settings.instances.contains_key(&uuid) {
                        eprintln!("No instances were found by that UUID.");
                        return Ok(ExitCode::FAILURE);
                    }

                    settings.selected_instance = Some(uuid);
                    settings.save().await?;

                    return Ok(ExitCode::SUCCESS);
                }

                let search_norm = args.instance.to_lowercase();

                let found: Vec<_> = settings.instances.iter()
                    .filter(|(_, inst)| {
                        // FIXME: find a better way of doing this matching
                        inst.name.to_lowercase().starts_with(&search_norm)
                    }).collect();

                if found.is_empty() {
                    eprintln!("No instances were found.");
                    return Ok(ExitCode::FAILURE);
                }

                if found.len() > 1 {
                    eprintln!("Ambiguous argument. Found {} instances:", found.len());
                    for (id, inst) in found {
                        eprintln!("- {} ({id})", inst.name);
                    }

                    return Ok(ExitCode::FAILURE);
                }

                let (found_id, found_inst) = found.first().unwrap();
                println!("Selected instance {} ({found_id}).", found_inst.name);

                settings.selected_instance = Some(**found_id);
                settings.save().await?;
            },
            InstanceCommand::Set(args) => {
                let Some(inst) = settings.get_selected_instance_mut() else {
                    eprintln!("No instance selected.");
                    return Ok(ExitCode::FAILURE);
                };

                args.apply_to(inst);
                settings.save().await?;
            },
            InstanceCommand::Delete => {
                let Some(inst) = settings.selected_instance else {
                    eprintln!("No instance selected.");
                    return Ok(ExitCode::FAILURE);
                };

                settings.instances.remove(&inst);
                settings.selected_instance = None;
                settings.save().await?;
            },
            InstanceCommand::Info => {
                let Some(inst) = settings.get_selected_instance() else {
                    eprintln!("No instance selected.");
                    return Ok(ExitCode::FAILURE);
                };
                
                display_instance(inst, settings.selected_instance.unwrap(), &home, false, true);
            },
            InstanceCommand::Rename { name } => {
                if name.is_empty() {
                    eprintln!("The instance must not have an empty name.");
                    return Ok(ExitCode::FAILURE);
                }

                let Some(inst) = settings.get_selected_instance_mut() else {
                    eprintln!("No instance selected.");
                    return Ok(ExitCode::FAILURE);
                };

                inst.name.replace_range(.., name);
                settings.save().await?;
            }
        },
        RootCommand::Launch => {
            let Some(selection) = settings.selected_instance else {
                eprintln!("No instance selected.");
                return Ok(ExitCode::FAILURE);
            };
            
            let inst = settings.instances.get(&selection).expect("settings inconsistency");

            settings.save().await?;

            let launcher = Launcher::new(&home, !cli.offline).await?;

            let launch = launcher.prepare_launch(inst, Settings::get_instance_path(selection), settings.client_id).await.map_err(|e| {
                error!("error launching: {e}");
                e
            })?;

            dbg!(&launch);
            info!("ok");

            ozone::launcher::run_the_game(&launch)?;
        }
        _ => todo!()
    }

    Ok(ExitCode::SUCCESS)
}

#[tokio::main]
async fn main() -> ExitCode {
    // use Warn as the default level to minimize noise on the command line
    simple_logger::SimpleLogger::new().with_level(LevelFilter::Warn).env().init().unwrap();

    let arg = Cli::parse();

    main_inner(arg).await.unwrap_or_else(|e| {
        error!("Launcher initialization error:");
        error!("{e}");

        ExitCode::FAILURE
    })
}