use clap::{App, Arg};
use cursive::traits::*;
use cursive::views::{Checkbox, Dialog, ListView, ProgressBar, TextView};
use cursive::Cursive;
use failure::Error;
use lazy_static::lazy_static;
use std::ffi::OsStr;
use std::os::unix::process::CommandExt;
use std::path::PathBuf;
use std::process::Command;
use std::sync::{Arc, Mutex};

use crate::registry::Registry;

mod registry;

lazy_static! {
    static ref REGISTRY: Arc<Mutex<Registry>> = Arc::new(Mutex::new(Registry::default()));
}

fn main() -> Result<(), Error> {
    let matches = App::new("Music Sync")
        .version("0.1.0")
        .author("Paul van Tilburg <paul@luon.net>")
        .about("Syncs selected music (albums) to a remote location using rsync")
        .arg(Arg::with_name("device").index(1).required(true))
        .arg(Arg::with_name("directory").index(2).required(true))
        .get_matches();
    let device = matches.value_of("device").unwrap();
    let base_path = matches.value_of("directory").unwrap();
    {
        let mut registry = REGISTRY.lock().unwrap();
        registry.device = String::from(device);
        registry.base_path = PathBuf::from(base_path);
    }

    let mut ui = Cursive::default();
    load_albums(&mut ui);

    ui.set_fps(10);
    ui.run();
    Ok(())
}

fn load_albums(ui: &mut Cursive) {
    let mut registry = REGISTRY.lock().unwrap();
    if let Err(error) = registry.load_albums_file() {
        eprintln!("Something went wrong: {}", error);
        quit(ui);
    }

    let cb = ui.cb_sink().clone();
    ui.add_layer(
        Dialog::around(
            ProgressBar::new()
                .range(0, registry.albums_list.len())
                .with_task(move |counter| {
                    let mut registry = REGISTRY.lock().unwrap();
                    if let Err(error) = registry.load_albums_fs(&counter) {
                        eprintln!("Something went wrong: {}", error);
                        cb.send(Box::new(quit));
                    } else {
                        cb.send(Box::new(select_albums));
                    }
                }),
        ).title("Loading list of albums…"),
    );
}

fn album_name(album_path: &PathBuf) -> &str {
    album_path
        .file_name()
        .unwrap_or_else(|| OsStr::new("<Couldn't determine filename>"))
        .to_str()
        .unwrap_or("<Non-UTF-8 characters found>")
}

fn select_albums(ui: &mut Cursive) {
    let registry = REGISTRY.lock().unwrap();
    let added_albums = registry.added_albums();
    let existing_albums = registry.existing_albums();
    let removed_albums = registry.removed_albums();
    // FIXME: Use a custom view for this.
    let list_view = ListView::new()
        .with(|list_view| {
            list_view.add_child("--- New", Checkbox::new().disabled());
            for album_path in added_albums {
                let album_name = album_name(&album_path);
                let album_path = album_path.clone();

                let checkbox = Checkbox::new().on_change(move |_, checked| {
                    let mut registry = REGISTRY.lock().unwrap();
                    registry.select_album(&album_path, checked);
                });
                list_view.add_child(album_name, checkbox);
            }
            list_view.add_child("--- Existing ", Checkbox::new().disabled());
            for album_path in existing_albums {
                let album_name = album_name(&album_path);
                let album_path = album_path.clone();
                let selected = registry.selected_albums.contains(&album_path);

                let mut checkbox = Checkbox::new().on_change(move |_, checked| {
                    let mut registry = REGISTRY.lock().unwrap();
                    registry.select_album(&album_path, checked);
                });
                if selected {
                    checkbox.check();
                }
                list_view.add_child(album_name, checkbox)
            }
            list_view.add_child("--- Gone ", Checkbox::new().disabled());
            for album_path in removed_albums {
                let mut checkbox = Checkbox::new().disabled();
                if registry.selected_albums.contains(album_path) {
                    checkbox.check();
                }
                list_view.add_child(album_name(album_path), checkbox);
            }
        }).scrollable();

    ui.pop_layer();
    ui.add_layer(
        Dialog::new()
            .title("Select or unselect albums")
            .button("Quit", |ui| quit(ui))
            .button("Apply", |ui| save_albums(ui))
            .content(list_view),
    );
}

fn save_albums(ui: &mut Cursive) {
    let registry = REGISTRY.lock().unwrap();
    if let Err(error) = registry.save_albums_file() {
        eprintln!("Something went wrong: {}", error);
        quit(ui);
    }

    ui.pop_layer();
    ui.add_layer(
        Dialog::around(TextView::new("All albums have been saved!\nSynchronise?"))
            .button("Yes", |ui| sync_albums(ui))
            .button("No", |ui| ui.quit()),
    );
}

fn sync_albums(ui: &mut Cursive) {
    let registry = REGISTRY.lock().unwrap();
    ui.quit();

    Command::new("echo")
        .arg("rsync")
        .arg("-vaP")
        .arg(&format!("--include-from={}.list.new", registry.device))
        .arg("--exclude=\"*\"")
        .arg("--delete")
        .arg(&registry.base_path)
        .arg("target_path")
        .exec();
}

fn quit(ui: &mut Cursive) {
    ui.quit();
}