use crossterm::{
    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode, KeyEventKind},
    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
};
use ratatui::{
    backend::{Backend, CrosstermBackend},
    layout::{Constraint, Direction, Layout},
    prelude::Alignment,
    style::Stylize,
    widgets::{Block, BorderType, Borders},
    Frame, Terminal,
};
use std::{error::Error, io};
use tui_vim_editor::{
    editor::{theme::EditorTheme, view::ViewState},
    input::Input,
    Buffer, Editor,
};

type Result<T> = std::result::Result<T, Box<dyn Error>>;

fn main() -> Result<()> {
    let mut terminal = init_terminal()?;

    let app = App::new();
    run_app(&mut terminal, app).unwrap();

    reset_terminal()?;
    terminal.show_cursor()?;

    Ok(())
}

/// Initializes the terminal.
fn init_terminal() -> Result<Terminal<CrosstermBackend<io::Stdout>>> {
    crossterm::execute!(io::stdout(), EnterAlternateScreen, EnableMouseCapture)?;
    enable_raw_mode()?;

    let backend = CrosstermBackend::new(io::stdout());

    let mut terminal = Terminal::new(backend)?;
    terminal.hide_cursor()?;

    // Shutdown gracefully
    let original_hook = std::panic::take_hook();

    std::panic::set_hook(Box::new(move |panic| {
        reset_terminal().unwrap();
        original_hook(panic);
    }));

    Ok(terminal)
}

/// Resets the terminal.
fn reset_terminal() -> Result<()> {
    disable_raw_mode()?;
    crossterm::execute!(io::stdout(), LeaveAlternateScreen, DisableMouseCapture)?;

    Ok(())
}

pub struct App {
    buffer: Buffer,
    state: ViewState,
}

impl App {
    pub fn new() -> App {
        let mut buffer = Buffer::new();
        buffer.push("\"Hello\", world");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("\"Hello\", world");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("\"Hello\", world");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("\"Hello\", world");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("\"Hello\", world");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        buffer.push("123 Boom.");
        // let clipboard: Box<dyn Clipboard> = Box::new(&CLIPBOARD);
        // buffer.set_clipboard(clipboard);
        let state = ViewState::default();
        App { buffer, state }
    }
}

pub fn run_app<B: Backend>(terminal: &mut Terminal<B>, mut app: App) -> io::Result<()> {
    let mut input = Input::default();
    loop {
        terminal.draw(|f| ui(f, &mut app))?;

        if let Event::Key(key) = event::read()? {
            if key.kind == KeyEventKind::Press {
                match key.code {
                    KeyCode::Char('q') => return Ok(()),
                    _ => input.on_key(key, &mut app.buffer),
                }
            }
        }
    }
}

pub fn ui(f: &mut Frame, app: &mut App) {
    let chunks = Layout::default()
        .direction(Direction::Horizontal)
        .constraints([Constraint::Min(0)].as_ref())
        .split(f.size());
    let theme = EditorTheme::default()
        .block(
            Block::default()
                .borders(Borders::ALL)
                .border_type(BorderType::Thick)
                .title("Editor")
                .title_alignment(Alignment::Center),
        )
        .base(EditorTheme::default().base.bold());

    let editor = Editor::new(&app.buffer, &mut app.state).theme(theme);

    f.render_widget(editor, chunks[0]);
}