use crate::app::state::TextEditor;
use crate::io;
use eframe::egui;

#[derive(Debug, Clone, Copy)]
enum ShortcutAction {
    NewFile,
    OpenFile,
    SaveFile,
    SaveAsFile,
    NewTab,
    CloseTab,
    ToggleLineNumbers,
    ToggleLineSide,
    ToggleWordWrap,
    ToggleAutoHideToolbar,
    ToggleFind,
    FocusFind,
    NextTab,
    PrevTab,
    PageUp,
    PageDown,
    ZoomIn,
    ZoomOut,
    GlobalZoomIn,
    GlobalZoomOut,
    ResetZoom,
    Escape,
    Preferences,
    ToggleVimMode,
}

type ShortcutDefinition = (egui::Modifiers, egui::Key, ShortcutAction);

fn get_shortcuts() -> Vec<ShortcutDefinition> {
    vec![
        (egui::Modifiers::CTRL, egui::Key::N, ShortcutAction::NewFile),
        (
            egui::Modifiers::CTRL,
            egui::Key::O,
            ShortcutAction::OpenFile,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::S,
            ShortcutAction::SaveAsFile,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::S,
            ShortcutAction::SaveFile,
        ),
        (egui::Modifiers::CTRL, egui::Key::T, ShortcutAction::NewTab),
        (
            egui::Modifiers::CTRL,
            egui::Key::W,
            ShortcutAction::CloseTab,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::F,
            ShortcutAction::FocusFind,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::F,
            ShortcutAction::ToggleFind,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::L,
            ShortcutAction::ToggleLineSide,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::L,
            ShortcutAction::ToggleLineNumbers,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::K,
            ShortcutAction::ToggleWordWrap,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::H,
            ShortcutAction::ToggleAutoHideToolbar,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::Tab,
            ShortcutAction::PrevTab,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::Tab,
            ShortcutAction::NextTab,
        ),
        (
            egui::Modifiers::NONE,
            egui::Key::PageUp,
            ShortcutAction::PageUp,
        ),
        (
            egui::Modifiers::NONE,
            egui::Key::PageDown,
            ShortcutAction::PageDown,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::Equals,
            ShortcutAction::ZoomIn,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::Minus,
            ShortcutAction::GlobalZoomOut,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::Minus,
            ShortcutAction::ZoomOut,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::Plus,
            ShortcutAction::GlobalZoomIn,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::Num0,
            ShortcutAction::ResetZoom,
        ),
        (
            egui::Modifiers::CTRL,
            egui::Key::P,
            ShortcutAction::Preferences,
        ),
        (
            egui::Modifiers::CTRL | egui::Modifiers::SHIFT,
            egui::Key::Period,
            ShortcutAction::ToggleVimMode,
        ),
        (
            egui::Modifiers::NONE,
            egui::Key::Escape,
            ShortcutAction::Escape,
        ),
    ]
}

fn execute_action(action: ShortcutAction, editor: &mut TextEditor, _ctx: &egui::Context) -> bool {
    match action {
        ShortcutAction::NewFile => {
            io::new_file(editor);
            false
        }
        ShortcutAction::OpenFile => {
            io::open_file(editor);
            false
        }
        ShortcutAction::SaveFile => {
            io::save_file(editor);
            false
        }
        ShortcutAction::SaveAsFile => {
            io::save_as_file(editor);
            false
        }
        ShortcutAction::NewTab => {
            editor.add_new_tab();
            false
        }
        ShortcutAction::CloseTab => {
            if editor.tabs.len() > 1 {
                if let Some(current_tab) = editor.get_active_tab() {
                    if current_tab.is_modified {
                        editor.pending_unsaved_action = Some(
                            super::state::UnsavedAction::CloseTab(editor.active_tab_index),
                        );
                    } else {
                        editor.close_tab(editor.active_tab_index);
                    }
                }
            }
            false
        }
        ShortcutAction::ToggleLineNumbers => {
            editor.show_line_numbers = !editor.show_line_numbers;
            editor.save_config();
            false
        }
        ShortcutAction::ToggleLineSide => {
            editor.line_side = !editor.line_side;
            editor.save_config();
            false
        }
        ShortcutAction::ToggleWordWrap => {
            editor.word_wrap = !editor.word_wrap;
            editor.save_config();
            false
        }
        ShortcutAction::ToggleAutoHideToolbar => {
            editor.auto_hide_toolbar = !editor.auto_hide_toolbar;
            editor.save_config();
            false
        }
        ShortcutAction::NextTab => {
            let next_tab_index = editor.active_tab_index + 1;
            if next_tab_index < editor.tabs.len() {
                editor.switch_to_tab(next_tab_index);
            } else {
                editor.switch_to_tab(0);
            }
            false
        }
        ShortcutAction::PrevTab => {
            if editor.active_tab_index == 0 {
                editor.switch_to_tab(editor.tabs.len() - 1);
            } else {
                editor.switch_to_tab(editor.active_tab_index - 1);
            }
            false
        }
        ShortcutAction::PageUp => false,
        ShortcutAction::PageDown => false,
        ShortcutAction::ZoomIn => {
            editor.font_size += 1.0;
            true
        }
        ShortcutAction::ZoomOut => {
            editor.font_size -= 1.0;
            true
        }
        ShortcutAction::GlobalZoomIn => {
            editor.zoom_factor += 0.1;
            false
        }
        ShortcutAction::GlobalZoomOut => {
            editor.zoom_factor -= 0.1;
            if editor.zoom_factor < 0.1 {
                editor.zoom_factor = 0.1;
            }
            false
        }
        ShortcutAction::ResetZoom => {
            editor.zoom_factor = 1.0;
            false
        }
        ShortcutAction::ToggleVimMode => {
            // editor.vim_mode = !editor.vim_mode;
            false
        }
        ShortcutAction::Escape => {
            editor.show_about = false;
            editor.show_shortcuts = false;
            if editor.show_find {
                editor.should_select_current_match = true;
            }
            editor.show_find = false;
            editor.show_preferences = false;
            editor.pending_unsaved_action = None;
            false
        }
        ShortcutAction::ToggleFind => {
            editor.show_find = !editor.show_find;
            if editor.show_find && !editor.find_query.is_empty() {
                editor.update_find_matches();
            }
            false
        }
        ShortcutAction::FocusFind => {
            if editor.show_find {
                editor.focus_find = true;
            }
            false
        }
        ShortcutAction::Preferences => {
            editor.show_preferences = !editor.show_preferences;
            false
        }
    }
}

pub fn handle(editor: &mut TextEditor, ctx: &egui::Context) {
    let mut font_zoom_occurred = false;
    let mut global_zoom_occurred = false;

    ctx.input_mut(|i| {
        for (modifiers, key, action) in get_shortcuts() {
            if i.consume_key(modifiers, key) {
                match action {
                    ShortcutAction::ZoomIn | ShortcutAction::ZoomOut => {
                        font_zoom_occurred = execute_action(action, editor, ctx);
                    }
                    ShortcutAction::GlobalZoomIn
                    | ShortcutAction::GlobalZoomOut
                    | ShortcutAction::ResetZoom => {
                        execute_action(action, editor, ctx);
                        global_zoom_occurred = true;
                    }
                    _ => {
                        execute_action(action, editor, ctx);
                    }
                }
                break;
            }
        }
    });

    if font_zoom_occurred {
        editor.apply_font_settings(ctx);
    }

    if global_zoom_occurred {
        ctx.set_zoom_factor(editor.zoom_factor);
    }

    if editor.should_select_current_match {
        editor.select_current_match(ctx);
        editor.should_select_current_match = false;
    }
}