use super::{
    highlighter::ReplHighlighter, prompt::ReplPrompt, validator::ReplValidator, REPL_COMMANDS,
};

use crate::config::SharedConfig;

use anyhow::Result;
use reedline::{
    default_emacs_keybindings, default_vi_insert_keybindings, default_vi_normal_keybindings,
    ColumnarMenu, DefaultCompleter, EditMode, Emacs, KeyCode, KeyModifiers, Keybindings, Reedline,
    ReedlineEvent, ReedlineMenu, Vi,
};

const MENU_NAME: &str = "completion_menu";

pub struct Repl {
    pub(crate) editor: Reedline,
    pub(crate) prompt: ReplPrompt,
}

impl Repl {
    pub fn init(config: SharedConfig) -> Result<Self> {
        let commands: Vec<String> = REPL_COMMANDS
            .into_iter()
            .map(|(v, _)| v.to_string())
            .collect();

        let completer = Self::create_completer(&config, &commands);
        let highlighter = ReplHighlighter::new(config.clone(), commands);
        let menu = Self::create_menu();
        let edit_mode: Box<dyn EditMode> = if config.read().keybindings.is_vi() {
            let mut normal_keybindings = default_vi_normal_keybindings();
            let mut insert_keybindings = default_vi_insert_keybindings();
            Self::extra_keybindings(&mut normal_keybindings);
            Self::extra_keybindings(&mut insert_keybindings);
            Box::new(Vi::new(insert_keybindings, normal_keybindings))
        } else {
            let mut keybindings = default_emacs_keybindings();
            Self::extra_keybindings(&mut keybindings);
            Box::new(Emacs::new(keybindings))
        };
        let mut editor = Reedline::create()
            .with_completer(Box::new(completer))
            .with_highlighter(Box::new(highlighter))
            .with_menu(menu)
            .with_edit_mode(edit_mode)
            .with_quick_completions(true)
            .with_partial_completions(true)
            .with_validator(Box::new(ReplValidator))
            .with_ansi_colors(true);
        editor.enable_bracketed_paste()?;
        let prompt = ReplPrompt::new(config);
        Ok(Self { editor, prompt })
    }

    fn create_completer(config: &SharedConfig, commands: &[String]) -> DefaultCompleter {
        let mut completion = commands.to_vec();
        completion.extend(config.read().repl_completions());
        let mut completer =
            DefaultCompleter::with_inclusions(&['.', '-', '_', ':']).set_min_word_len(2);
        completer.insert(completion.clone());
        completer
    }

    fn extra_keybindings(keybindings: &mut Keybindings) {
        keybindings.add_binding(
            KeyModifiers::NONE,
            KeyCode::Tab,
            ReedlineEvent::UntilFound(vec![
                ReedlineEvent::Menu(MENU_NAME.to_string()),
                ReedlineEvent::MenuNext,
            ]),
        );
        keybindings.add_binding(
            KeyModifiers::CONTROL,
            KeyCode::Char('s'),
            ReedlineEvent::Submit,
        );
    }

    fn create_menu() -> ReedlineMenu {
        let completion_menu = ColumnarMenu::default().with_name(MENU_NAME);
        ReedlineMenu::EngineCompleter(Box::new(completion_menu))
    }
}