// bibiman - a TUI for managing BibLaTeX databases
// Copyright (C) 2024  lukeflo
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
/////

use crate::frontend::app::App;
use crate::frontend::event::EventHandler;
use color_eyre::eyre::Result;
use crossterm::event::{DisableMouseCapture, EnableMouseCapture};
use crossterm::terminal::{self, EnterAlternateScreen, LeaveAlternateScreen};
use ratatui::backend::{Backend, CrosstermBackend};
// use ratatui::backend::CrosstermBackend as Backend;
use ratatui::Terminal;
use std::io::{self, stdout, Stdout};
use std::panic;
use std::{
    ops::{Deref, DerefMut},
    time::Duration,
};

// pub type IO = std::io::{{crossterm_io | title_case}};
// pub fn io() -> IO {
//   std::io::{{crossterm_io}}()
// }
/// Representation of a terminal user interface.
///
/// It is responsible for setting up the terminal,
/// initializing the interface and handling the draw events.
#[derive(Debug)]
pub struct Tui {
    /// Interface to the Terminal.
    terminal: ratatui::Terminal<CrosstermBackend<Stdout>>,
    /// Terminal event handler.
    pub events: EventHandler,
}

impl Tui {
    /// Constructs a new instance of [`Tui`].
    pub fn new() -> Result<Self> {
        let backend = CrosstermBackend::new(stdout());
        let terminal = Terminal::new(backend)?;
        let events = EventHandler::new(250);
        Ok(Self { terminal, events })
    }

    /// Initializes the terminal interface.
    ///
    /// It enables the raw mode and sets terminal properties.
    pub fn init(&mut self) -> Result<()> {
        terminal::enable_raw_mode()?;
        crossterm::execute!(io::stdout(), EnterAlternateScreen, EnableMouseCapture)?;

        // Define a custom panic hook to reset the terminal properties.
        // This way, you won't have your terminal messed up if an unexpected error happens.
        let panic_hook = panic::take_hook();
        panic::set_hook(Box::new(move |panic| {
            Self::reset().expect("failed to reset the terminal");
            panic_hook(panic);
        }));

        self.terminal.hide_cursor()?;
        self.terminal.clear()?;
        Ok(())
    }

    /// [`Draw`] the terminal interface by [`rendering`] the widgets.
    ///
    /// [`Draw`]: ratatui::Terminal::draw
    /// [`rendering`]: crate::ui::render
    pub fn draw(&mut self, app: &mut App) -> Result<()> {
        // self.terminal.draw(|frame| ui::render(app, frame))?;
        self.terminal
            .draw(|frame| frame.render_widget(app, frame.area()))?;
        Ok(())
    }

    /// Resets the terminal interface.
    ///
    /// This function is also used for the panic hook to revert
    /// the terminal properties if unexpected errors occur.
    fn reset() -> Result<()> {
        terminal::disable_raw_mode()?;
        crossterm::execute!(io::stdout(), LeaveAlternateScreen, DisableMouseCapture)?;
        Ok(())
    }

    /// Exits the terminal interface.
    ///
    /// It disables the raw mode and reverts back the terminal properties.
    pub fn exit(&mut self) -> Result<()> {
        Self::reset()?;
        self.terminal.show_cursor()?;
        Ok(())
    }
}