/*
 * Copyright (c) 2023, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "CalendarWidget.h"
#include "AddEventDialog.h"
#include <AK/JsonParser.h>
#include <AK/LexicalPath.h>
#include <Applications/Calendar/CalendarWindowGML.h>
#include <LibConfig/Client.h>
#include <LibCore/System.h>
#include <LibGUI/Action.h>
#include <LibGUI/ActionGroup.h>
#include <LibGUI/Application.h>
#include <LibGUI/BoxLayout.h>
#include <LibGUI/Calendar.h>
#include <LibGUI/Icon.h>
#include <LibGUI/Menu.h>
#include <LibGUI/Menubar.h>
#include <LibGUI/MessageBox.h>
#include <LibGUI/Process.h>
#include <LibGUI/Toolbar.h>
#include <LibGUI/Window.h>
#include <LibMain/Main.h>

namespace Calendar {

ErrorOr<NonnullRefPtr<CalendarWidget>> CalendarWidget::create(GUI::Window* parent_window)
{
    auto widget = TRY(AK::adopt_nonnull_ref_or_enomem(new (nothrow) CalendarWidget));
    TRY(widget->load_from_gml(calendar_window_gml));

    widget->m_event_calendar = widget->find_descendant_of_type_named<EventCalendar>("calendar");
    widget->create_on_events_change();

    auto toolbar = widget->find_descendant_of_type_named<GUI::Toolbar>("toolbar");
    auto calendar = widget->m_event_calendar;

    auto prev_date_action = TRY(widget->create_prev_date_action());
    auto next_date_action = TRY(widget->create_next_date_action());

    auto add_event_action = TRY(widget->create_add_event_action());

    auto jump_to_action = TRY(widget->create_jump_to_action());

    auto view_month_action = TRY(widget->create_view_month_action());
    view_month_action->set_checked(true);

    auto view_year_action = TRY(widget->create_view_year_action());
    auto view_type_action_group = make<GUI::ActionGroup>();

    view_type_action_group->set_exclusive(true);
    view_type_action_group->add_action(*view_month_action);
    view_type_action_group->add_action(*view_year_action);
    auto default_view = Config::read_string("Calendar"sv, "View"sv, "DefaultView"sv, "Month"sv);
    if (default_view == "Year")
        view_year_action->set_checked(true);

    auto open_settings_action = TRY(widget->create_open_settings_action());

    (void)TRY(toolbar->try_add_action(prev_date_action));
    (void)TRY(toolbar->try_add_action(next_date_action));
    TRY(toolbar->try_add_separator());
    (void)TRY(toolbar->try_add_action(jump_to_action));
    (void)TRY(toolbar->try_add_action(add_event_action));
    TRY(toolbar->try_add_separator());
    (void)TRY(toolbar->try_add_action(view_month_action));
    (void)TRY(toolbar->try_add_action(view_year_action));
    (void)TRY(toolbar->try_add_action(open_settings_action));

    widget->create_on_tile_doubleclick();

    calendar->on_month_click = [&] {
        view_month_action->set_checked(true);
    };

    auto new_calendar_action = TRY(widget->create_new_calendar_action());
    auto open_calendar_action = widget->create_open_calendar_action();

    auto save_as_action = widget->create_save_as_action();
    auto save_action = widget->create_save_action(save_as_action);

    auto& file_menu = parent_window->add_menu("&File"_string);
    file_menu.add_action(open_settings_action);
    file_menu.add_action(new_calendar_action);
    file_menu.add_action(open_calendar_action);
    file_menu.add_action(save_as_action);
    file_menu.add_action(save_action);

    TRY(file_menu.try_add_separator());

    TRY(file_menu.try_add_action(GUI::CommonActions::make_quit_action([](auto&) {
        GUI::Application::the()->quit();
    })));

    auto& event_menu = parent_window->add_menu("&Event"_string);
    event_menu.add_action(add_event_action);

    auto view_menu = TRY(parent_window->try_add_menu("&View"_string));
    TRY(view_menu->try_add_action(*view_month_action));
    TRY(view_menu->try_add_action(*view_year_action));

    auto help_menu = TRY(parent_window->try_add_menu("&Help"_string));
    TRY(help_menu->try_add_action(GUI::CommonActions::make_command_palette_action(parent_window)));
    TRY(help_menu->try_add_action(GUI::CommonActions::make_about_action("Calendar", TRY(GUI::Icon::try_create_default_icon("app-calendar"sv)), parent_window)));

    return widget;
}

void CalendarWidget::create_on_events_change()
{
    m_event_calendar->event_manager().on_events_change = [&]() {
        m_event_calendar->repaint();
        window()->set_modified(true);
        update_window_title();
    };
}

void CalendarWidget::load_file(FileSystemAccessClient::File file)
{
    auto result = m_event_calendar->event_manager().load_file(file);
    if (result.is_error()) {
        GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Cannot load file: {}", result.error()));
        return;
    }

    window()->set_modified(false);
    update_window_title();
}

NonnullRefPtr<GUI::Action> CalendarWidget::create_save_action(GUI::Action& save_as_action)
{
    return GUI::CommonActions::make_save_action([&](auto&) {
        if (current_filename().is_empty()) {
            save_as_action.activate();
            return;
        }

        auto response = FileSystemAccessClient::Client::the().request_file(window(), current_filename().to_deprecated_string(), Core::File::OpenMode::Write);
        if (response.is_error())
            return;

        auto result = m_event_calendar->event_manager().save(response.value());
        if (result.is_error()) {
            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Cannot save file: {}", result.error()));
            return;
        }

        window()->set_modified(false);
        update_window_title();
    });
}

NonnullRefPtr<GUI::Action> CalendarWidget::create_save_as_action()
{
    return GUI::CommonActions::make_save_as_action([&](auto&) {
        auto response = FileSystemAccessClient::Client::the().save_file(window(), "calendar", "cal");
        if (response.is_error())
            return;

        auto result = m_event_calendar->event_manager().save(response.value());
        if (result.is_error()) {
            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Cannot save file: {}", result.error()));
            return;
        }

        window()->set_modified(false);
        update_window_title();
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_new_calendar_action()
{
    return GUI::Action::create("&New Calendar", {}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/app-calendar.png"sv)), [&](const GUI::Action&) {
        auto response = FileSystemAccessClient::Client::the().save_file(window(), "calendar", "cal", Core::File::OpenMode::Write);

        if (response.is_error())
            return;

        m_event_calendar->event_manager().clear();

        auto result = m_event_calendar->event_manager().save(response.value());
        if (result.is_error()) {
            GUI::MessageBox::show_error(window(), DeprecatedString::formatted("Cannot save file: {}", result.error()));
            return;
        }

        update_window_title();
    });
}

NonnullRefPtr<GUI::Action> CalendarWidget::create_open_calendar_action()
{
    return GUI::CommonActions::make_open_action([&](auto&) {
        auto response = FileSystemAccessClient::Client::the().open_file(window());
        if (response.is_error())
            return;
        (void)load_file(response.release_value());
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_prev_date_action()
{
    return GUI::Action::create({}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/go-back.png"sv)), [&](const GUI::Action&) {
        m_event_calendar->show_previous_date();
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_next_date_action()
{
    return GUI::Action::create({}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/go-forward.png"sv)), [&](const GUI::Action&) {
        m_event_calendar->show_next_date();
    });
}

void CalendarWidget::update_window_title()
{
    StringBuilder builder;
    if (current_filename().is_empty())
        builder.append("Untitled"sv);
    else
        builder.append(current_filename());
    builder.append("[*] - Calendar"sv);

    window()->set_title(builder.to_deprecated_string());
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_add_event_action()
{
    return GUI::Action::create("&Add Event", {}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/add-event.png"sv)), [&](const GUI::Action&) {
        AddEventDialog::show(m_event_calendar->selected_date(), m_event_calendar->event_manager(), window());
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_jump_to_action()
{
    return GUI::Action::create("Jump to &Today", {}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/calendar-date.png"sv)), [&](const GUI::Action&) {
        m_event_calendar->set_selected_date(Core::DateTime::now());
        m_event_calendar->update_tiles(Core::DateTime::now().year(), Core::DateTime::now().month());
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_view_month_action()
{
    return GUI::Action::create_checkable("&Month View", { Mod_Ctrl, KeyCode::Key_1 }, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/calendar-month-view.png"sv)), [&](const GUI::Action&) {
        if (m_event_calendar->mode() == GUI::Calendar::Year)
            m_event_calendar->toggle_mode();
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_view_year_action()
{
    return GUI::Action::create_checkable("&Year View", { Mod_Ctrl, KeyCode::Key_2 }, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/icon-view.png"sv)), [&](const GUI::Action&) {
        if (m_event_calendar->mode() == GUI::Calendar::Month)
            m_event_calendar->toggle_mode();
    });
}

ErrorOr<NonnullRefPtr<GUI::Action>> CalendarWidget::create_open_settings_action()
{
    return GUI::Action::create("Calendar &Settings", {}, TRY(Gfx::Bitmap::load_from_file("/res/icons/16x16/app-settings.png"sv)), [&](GUI::Action const&) {
        GUI::Process::spawn_or_show_error(window(), "/bin/CalendarSettings"sv);
    });
}

void CalendarWidget::create_on_tile_doubleclick()
{
    m_event_calendar->on_tile_doubleclick = [&] {
        AddEventDialog::show(m_event_calendar->selected_date(), m_event_calendar->event_manager(), window());
    };
}

}