#include <Tactility/Tactility.h>

#include <tactility/lvgl_icon_shared.h>

#ifdef ESP_PLATFORM
#include <Tactility/service/displayidle/DisplayIdleService.h>
#endif

#include <Tactility/Logger.h>
#include <Tactility/app/App.h>
#include <Tactility/hal/display/DisplayDevice.h>
#include <Tactility/hal/touch/TouchDevice.h>
#include <Tactility/lvgl/Toolbar.h>
#include <Tactility/settings/DisplaySettings.h>

#include <lvgl.h>
#include <tactility/lvgl_module.h>

namespace tt::app::display {

static const auto LOGGER = Logger("Display");

static std::shared_ptr<hal::display::DisplayDevice> getHalDisplay() {
    return hal::findFirstDevice<hal::display::DisplayDevice>(hal::Device::Type::Display);
}

static bool hasCalibratableTouchDevice() {
    auto touch_devices = hal::findDevices<hal::touch::TouchDevice>(hal::Device::Type::Touch);
    for (const auto& touch_device : touch_devices) {
        if (touch_device != nullptr && touch_device->supportsCalibration()) {
            return true;
        }
    }
    return false;
}

class DisplayApp final : public App {

    settings::display::DisplaySettings displaySettings;
    bool displaySettingsUpdated = false;
    lv_obj_t* timeoutSwitch = nullptr;
    lv_obj_t* timeoutDropdown = nullptr;
    lv_obj_t* screensaverDropdown = nullptr;
    lv_obj_t* disableWhenChargingWrapper = nullptr;
    lv_obj_t* disableWhenChargingSwitch = nullptr;

    static void onBacklightSliderEvent(lv_event_t* event) {
        auto* slider = static_cast<lv_obj_t*>(lv_event_get_target(event));
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto hal_display = getHalDisplay();
        assert(hal_display != nullptr);

        if (hal_display->supportsBacklightDuty()) {
            int32_t slider_value = lv_slider_get_value(slider);
            app->displaySettings.backlightDuty = static_cast<uint8_t>(slider_value);
            app->displaySettingsUpdated = true;
            hal_display->setBacklightDuty(app->displaySettings.backlightDuty);
        }
    }

    static void onGammaSliderEvent(lv_event_t* event) {
        auto* slider = static_cast<lv_obj_t*>(lv_event_get_target(event));
        auto hal_display = hal::findFirstDevice<hal::display::DisplayDevice>(hal::Device::Type::Display);
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        assert(hal_display != nullptr);

        if (hal_display->getGammaCurveCount() > 0) {
            int32_t slider_value = lv_slider_get_value(slider);
            app->displaySettings.gammaCurve = static_cast<uint8_t>(slider_value);
            app->displaySettingsUpdated = true;
            hal_display->setGammaCurve(app->displaySettings.gammaCurve);
        }
    }

    static void onOrientationSet(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
        uint32_t selected_index = lv_dropdown_get_selected(dropdown);
        LOGGER.info("Selected {}", selected_index);
        auto selected_orientation = static_cast<settings::display::Orientation>(selected_index);
        if (selected_orientation != app->displaySettings.orientation) {
            app->displaySettings.orientation = selected_orientation;
            app->displaySettingsUpdated = true;
            lv_display_set_rotation(lv_display_get_default(), settings::display::toLvglDisplayRotation(selected_orientation));
        }
    }

    static void onTimeoutSwitch(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
        bool enabled = lv_obj_has_state(sw, LV_STATE_CHECKED);
        app->displaySettings.backlightTimeoutEnabled = enabled;
        app->displaySettingsUpdated = true;
        if (app->timeoutDropdown) {
            if (enabled) {
                lv_obj_clear_state(app->timeoutDropdown, LV_STATE_DISABLED);
                if (app->screensaverDropdown) {
                    lv_obj_clear_state(app->screensaverDropdown, LV_STATE_DISABLED);
                }
                if (app->disableWhenChargingWrapper) {
                    lv_obj_clear_state(app->disableWhenChargingWrapper, LV_STATE_DISABLED);
                }
            } else {
                lv_obj_add_state(app->timeoutDropdown, LV_STATE_DISABLED);
                if (app->screensaverDropdown) {
                    lv_obj_add_state(app->screensaverDropdown, LV_STATE_DISABLED);
                }
                if (app->disableWhenChargingWrapper) {
                    lv_obj_add_state(app->disableWhenChargingWrapper, LV_STATE_DISABLED);
                }
            }
        }
    }

    static void onDisableWhenChargingChanged(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
        bool enabled = lv_obj_has_state(sw, LV_STATE_CHECKED);
        app->displaySettings.disableScreensaverWhenCharging = enabled;
        app->displaySettingsUpdated = true;
    }

    static void onInvertColorChanged(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
        bool enabled = lv_obj_has_state(sw, LV_STATE_CHECKED);
        app->displaySettings.invertColor = enabled;
        app->displaySettingsUpdated = true;
        // Apply immediately
        auto hal_display = getHalDisplay();
        if (hal_display && hal_display->supportsInvertColor()) {
            hal_display->setInvertColor(enabled);
        }
    }

    static void onMonoThresholdChanged(lv_event_t* event) {
        auto* slider = static_cast<lv_obj_t*>(lv_event_get_target(event));
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        int32_t val = lv_slider_get_value(slider);
        if (val < 1) val = 1;
        if (val > 255) val = 255;
        app->displaySettings.monochromeThreshold = static_cast<uint8_t>(val);
        app->displaySettingsUpdated = true;
        auto hal_display = getHalDisplay();
        if (hal_display && hal_display->supportsMonochromeThreshold()) {
            hal_display->setMonochromeThreshold(static_cast<uint8_t>(val));
        }
    }

    static void onMonoThresholdChanging(lv_event_t* event) {
        auto* slider = static_cast<lv_obj_t*>(lv_event_get_target(event));
        auto* value_label = static_cast<lv_obj_t*>(lv_event_get_user_data(event));
        if (value_label) {
            int32_t v = lv_slider_get_value(slider);
            lv_label_set_text_fmt(value_label, "%d", (int)v);
        }
    }

    static void onTimeoutChanged(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
        uint32_t idx = lv_dropdown_get_selected(dropdown);
        // Map dropdown index to ms: 0=15s,1=30s,2=1m,3=2m,4=5m,5=Never
        static const uint32_t values_ms[] = {15000, 30000, 60000, 120000, 300000, 0};
        if (idx < (sizeof(values_ms)/sizeof(values_ms[0]))) {
            app->displaySettings.backlightTimeoutMs = values_ms[idx];
            app->displaySettingsUpdated = true;
        }
    }

    static void onScreensaverChanged(lv_event_t* event) {
        auto* app = static_cast<DisplayApp*>(lv_event_get_user_data(event));
        auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
        uint32_t idx = lv_dropdown_get_selected(dropdown);
        // Validate index bounds before casting to enum
        if (idx >= static_cast<uint32_t>(settings::display::ScreensaverType::Count)) {
            return;
        }
        auto selected_type = static_cast<settings::display::ScreensaverType>(idx);
        if (selected_type != app->displaySettings.screensaverType) {
            app->displaySettings.screensaverType = selected_type;
            app->displaySettingsUpdated = true;
        }
    }

    static void onCalibrateTouchClicked(lv_event_t*) {
        app::start("TouchCalibration");
    }

public:

    void onShow(AppContext& app, lv_obj_t* parent) override {
        displaySettings = settings::display::loadOrGetDefault();
        auto ui_density = lvgl_get_ui_density();

        lv_obj_set_flex_flow(parent, LV_FLEX_FLOW_COLUMN);
        lv_obj_set_style_pad_row(parent, 0, LV_STATE_DEFAULT);

        auto hal_display = getHalDisplay();
        assert(hal_display != nullptr);

        lvgl::toolbar_create(parent, app);

        auto* main_wrapper = lv_obj_create(parent);
        lv_obj_set_flex_flow(main_wrapper, LV_FLEX_FLOW_COLUMN);
        lv_obj_set_width(main_wrapper, LV_PCT(100));
        lv_obj_set_flex_grow(main_wrapper, 1);

        // Backlight slider

        if (hal_display->supportsBacklightDuty()) {
            auto* brightness_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(brightness_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_hor(brightness_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(brightness_wrapper, 0, LV_STATE_DEFAULT);
            if (ui_density != LVGL_UI_DENSITY_COMPACT) {
                lv_obj_set_style_pad_ver(brightness_wrapper, 4, LV_STATE_DEFAULT);
            }

            auto* brightness_label = lv_label_create(brightness_wrapper);
            lv_label_set_text(brightness_label, "Brightness");
            lv_obj_align(brightness_label, LV_ALIGN_LEFT_MID, 0, 0);

            auto* brightness_slider = lv_slider_create(brightness_wrapper);
            lv_obj_set_width(brightness_slider, LV_PCT(50));
            lv_obj_align(brightness_slider, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_slider_set_range(brightness_slider, 0, 255);
            lv_obj_add_event_cb(brightness_slider, onBacklightSliderEvent, LV_EVENT_VALUE_CHANGED, this);

            lv_slider_set_value(brightness_slider, displaySettings.backlightDuty, LV_ANIM_OFF);
        }

        // Gamma slider

        if (hal_display->getGammaCurveCount() > 0) {
            auto* gamma_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(gamma_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_hor(gamma_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(gamma_wrapper, 0, LV_STATE_DEFAULT);
            if (ui_density != LVGL_UI_DENSITY_COMPACT) {
                lv_obj_set_style_pad_ver(gamma_wrapper, 4, LV_STATE_DEFAULT);
            }

            auto* gamma_label = lv_label_create(gamma_wrapper);
            lv_label_set_text(gamma_label, "Gamma");
            lv_obj_align(gamma_label, LV_ALIGN_LEFT_MID, 0, 0);
            lv_obj_set_y(gamma_label, 0);

            auto* gamma_slider = lv_slider_create(gamma_wrapper);
            lv_obj_set_width(gamma_slider, LV_PCT(50));
            lv_obj_align(gamma_slider, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_slider_set_range(gamma_slider, 0, hal_display->getGammaCurveCount());
            lv_obj_add_event_cb(gamma_slider, onGammaSliderEvent, LV_EVENT_VALUE_CHANGED, this);

            uint8_t curve_index = displaySettings.gammaCurve;
            lv_slider_set_value(gamma_slider, curve_index, LV_ANIM_OFF);
        }

        // Orientation

        auto* orientation_wrapper = lv_obj_create(main_wrapper);
        lv_obj_set_size(orientation_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
        lv_obj_set_style_pad_all(orientation_wrapper, 0, LV_STATE_DEFAULT);
        lv_obj_set_style_border_width(orientation_wrapper, 0, LV_STATE_DEFAULT);

        auto* orientation_label = lv_label_create(orientation_wrapper);
        lv_label_set_text(orientation_label, "Orientation");
        lv_obj_align(orientation_label, LV_ALIGN_LEFT_MID, 0, 0);

        auto* orientation_dropdown = lv_dropdown_create(orientation_wrapper);
        // Note: order correlates with settings::display::Orientation item order
        lv_dropdown_set_options(orientation_dropdown, "Landscape\nPortrait Right\nLandscape Flipped\nPortrait Left");
        lv_obj_align(orientation_dropdown, LV_ALIGN_RIGHT_MID, 0, 0);
        lv_obj_add_event_cb(orientation_dropdown, onOrientationSet, LV_EVENT_VALUE_CHANGED, this);
        // Set the dropdown to match current orientation enum
        lv_dropdown_set_selected(orientation_dropdown, static_cast<uint16_t>(displaySettings.orientation));

        // Screen timeout

        if (hal_display->supportsBacklightDuty()) {
            auto* timeout_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(timeout_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_all(timeout_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(timeout_wrapper, 0, LV_STATE_DEFAULT);

            auto* timeout_label = lv_label_create(timeout_wrapper);
            lv_label_set_text(timeout_label, "Auto screen off");
            lv_obj_align(timeout_label, LV_ALIGN_LEFT_MID, 0, 0);

            timeoutSwitch = lv_switch_create(timeout_wrapper);
            if (displaySettings.backlightTimeoutEnabled) {
                lv_obj_add_state(timeoutSwitch, LV_STATE_CHECKED);
            }
            lv_obj_align(timeoutSwitch, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_obj_add_event_cb(timeoutSwitch, onTimeoutSwitch, LV_EVENT_VALUE_CHANGED, this);

            auto* timeout_select_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(timeout_select_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_all(timeout_select_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(timeout_select_wrapper, 0, LV_STATE_DEFAULT);

            auto* timeout_value_label = lv_label_create(timeout_select_wrapper);
            lv_label_set_text(timeout_value_label, "Timeout");
            lv_obj_align(timeout_value_label, LV_ALIGN_LEFT_MID, 0, 0);

            timeoutDropdown = lv_dropdown_create(timeout_select_wrapper);
            lv_dropdown_set_options(timeoutDropdown, "15 seconds\n30 seconds\n1 minute\n2 minutes\n5 minutes\nNever");
            lv_obj_align(timeoutDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_obj_add_event_cb(timeoutDropdown, onTimeoutChanged, LV_EVENT_VALUE_CHANGED, this);
            // Initialize dropdown selection from settings
            uint32_t ms = displaySettings.backlightTimeoutMs;
            uint32_t idx = 2; // default 1 minute
            if (ms == 15000) idx = 0;
            else if (ms == 30000)
                idx = 1;
            else if (ms == 60000)
                idx = 2;
            else if (ms == 120000)
                idx = 3;
            else if (ms == 300000)
                idx = 4;
            else if (ms == 0)
                idx = 5;
            lv_dropdown_set_selected(timeoutDropdown, idx);
            if (!displaySettings.backlightTimeoutEnabled) {
                lv_obj_add_state(timeoutDropdown, LV_STATE_DISABLED);
            }

            // Screensaver type
            auto* screensaver_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(screensaver_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_all(screensaver_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(screensaver_wrapper, 0, LV_STATE_DEFAULT);

            auto* screensaver_label = lv_label_create(screensaver_wrapper);
            lv_label_set_text(screensaver_label, "Screensaver");
            lv_obj_align(screensaver_label, LV_ALIGN_LEFT_MID, 0, 0);

            screensaverDropdown = lv_dropdown_create(screensaver_wrapper);
            // Note: order correlates with settings::display::ScreensaverType enum order
            lv_dropdown_set_options(screensaverDropdown, "None\nBouncing Balls\nMystify\nMatrix Rain\nStackChan\nMCP Screen");

            lv_obj_align(screensaverDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_obj_add_event_cb(screensaverDropdown, onScreensaverChanged, LV_EVENT_VALUE_CHANGED, this);
            lv_dropdown_set_selected(screensaverDropdown, static_cast<uint16_t>(displaySettings.screensaverType));
            if (!displaySettings.backlightTimeoutEnabled) {
                lv_obj_add_state(screensaverDropdown, LV_STATE_DISABLED);
            }

            // Disable screensaver when charging toggle
            disableWhenChargingWrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(disableWhenChargingWrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_all(disableWhenChargingWrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(disableWhenChargingWrapper, 0, LV_STATE_DEFAULT);

            auto* charging_label = lv_label_create(disableWhenChargingWrapper);
            lv_label_set_text(charging_label, "Disable on charging");
            lv_obj_align(charging_label, LV_ALIGN_LEFT_MID, 0, 0);

            disableWhenChargingSwitch = lv_switch_create(disableWhenChargingWrapper);
            if (displaySettings.disableScreensaverWhenCharging) {
                lv_obj_add_state(disableWhenChargingSwitch, LV_STATE_CHECKED);
            }
            lv_obj_align(disableWhenChargingSwitch, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_obj_add_event_cb(disableWhenChargingSwitch, onDisableWhenChargingChanged, LV_EVENT_VALUE_CHANGED, this);
            if (!displaySettings.backlightTimeoutEnabled) {
                lv_obj_add_state(disableWhenChargingWrapper, LV_STATE_DISABLED);
            }
        }

        // Invert color toggle (if display supports it - e.g. RLCD ST7305)
        {
            auto hal_disp = getHalDisplay();
            if (hal_disp && hal_disp->supportsInvertColor()) {
                auto* invert_wrapper = lv_obj_create(main_wrapper);
                lv_obj_set_size(invert_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
                lv_obj_set_style_pad_all(invert_wrapper, 0, LV_STATE_DEFAULT);
                lv_obj_set_style_border_width(invert_wrapper, 0, LV_STATE_DEFAULT);

                auto* invert_label = lv_label_create(invert_wrapper);
                lv_label_set_text(invert_label, "Invert colors");
                lv_obj_align(invert_label, LV_ALIGN_LEFT_MID, 0, 0);

                auto* invert_switch = lv_switch_create(invert_wrapper);
                if (displaySettings.invertColor) {
                    lv_obj_add_state(invert_switch, LV_STATE_CHECKED);
                }
                lv_obj_align(invert_switch, LV_ALIGN_RIGHT_MID, 0, 0);
                lv_obj_add_event_cb(invert_switch, onInvertColorChanged, LV_EVENT_VALUE_CHANGED, this);
            }
        }

        // Monochrome threshold slider (ST7305 reflective) - adjustable B/W cut
        {
            auto hal_disp = getHalDisplay();
            if (hal_disp && hal_disp->supportsMonochromeThreshold()) {
                auto* thresh_wrapper = lv_obj_create(main_wrapper);
                lv_obj_set_size(thresh_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
                lv_obj_set_style_pad_all(thresh_wrapper, 0, LV_STATE_DEFAULT);
                lv_obj_set_style_border_width(thresh_wrapper, 0, LV_STATE_DEFAULT);
                lv_obj_set_flex_flow(thresh_wrapper, LV_FLEX_FLOW_COLUMN);
                lv_obj_set_style_pad_row(thresh_wrapper, 2, LV_STATE_DEFAULT);

                auto* header_row = lv_obj_create(thresh_wrapper);
                lv_obj_set_size(header_row, LV_PCT(100), LV_SIZE_CONTENT);
                lv_obj_set_style_pad_all(header_row, 0, LV_STATE_DEFAULT);
                lv_obj_set_style_border_width(header_row, 0, LV_STATE_DEFAULT);

                auto* thresh_label = lv_label_create(header_row);
                lv_label_set_text(thresh_label, "Mono threshold");
                lv_obj_align(thresh_label, LV_ALIGN_LEFT_MID, 0, 0);

                auto* value_label = lv_label_create(header_row);
                lv_label_set_text_fmt(value_label, "%d", displaySettings.monochromeThreshold);
                lv_obj_align(value_label, LV_ALIGN_RIGHT_MID, 0, 0);

                auto* thresh_slider = lv_slider_create(thresh_wrapper);
                lv_obj_set_width(thresh_slider, LV_PCT(100));
                lv_slider_set_range(thresh_slider, 20, 230); // avoid extremes that make screen all black/white
                lv_slider_set_value(thresh_slider, displaySettings.monochromeThreshold, LV_ANIM_OFF);
                // Live label update: pass value_label as user_data
                lv_obj_add_event_cb(thresh_slider, onMonoThresholdChanging, LV_EVENT_VALUE_CHANGED, value_label);
                // Persist + apply: pass app as user_data
                lv_obj_add_event_cb(thresh_slider, onMonoThresholdChanged, LV_EVENT_VALUE_CHANGED, this);
                // Apply initial threshold live
                hal_disp->setMonochromeThreshold(displaySettings.monochromeThreshold);
            }
        }

        if (hasCalibratableTouchDevice()) {
            auto* calibrate_wrapper = lv_obj_create(main_wrapper);
            lv_obj_set_size(calibrate_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
            lv_obj_set_style_pad_all(calibrate_wrapper, 0, LV_STATE_DEFAULT);
            lv_obj_set_style_border_width(calibrate_wrapper, 0, LV_STATE_DEFAULT);

            auto* calibrate_label = lv_label_create(calibrate_wrapper);
            lv_label_set_text(calibrate_label, "Touch calibration");
            lv_obj_align(calibrate_label, LV_ALIGN_LEFT_MID, 0, 0);

            auto* calibrate_button = lv_button_create(calibrate_wrapper);
            lv_obj_align(calibrate_button, LV_ALIGN_RIGHT_MID, 0, 0);
            lv_obj_add_event_cb(calibrate_button, onCalibrateTouchClicked, LV_EVENT_SHORT_CLICKED, this);

            auto* calibrate_button_label = lv_label_create(calibrate_button);
            lv_label_set_text(calibrate_button_label, "Calibrate");
            lv_obj_center(calibrate_button_label);
        }
    }

    void onHide(AppContext& app) override {
        if (displaySettingsUpdated) {
            // Dispatch it, so file IO doesn't block the UI
            const settings::display::DisplaySettings settings_to_save = displaySettings;
            getMainDispatcher().dispatch([settings_to_save] {
                settings::display::save(settings_to_save);
#ifdef ESP_PLATFORM
                // Notify DisplayIdle service to reload settings
                auto displayIdle = service::displayidle::findService();
                if (displayIdle) {
                    displayIdle->reloadSettings();
                }
#endif
            });
        }
    }
};

extern const AppManifest manifest = {
    .appId = "Display",
    .appName = "Display",
    .appIcon = LVGL_ICON_SHARED_DISPLAY_SETTINGS,
    .appCategory = Category::Settings,
    .createApp = create<DisplayApp>
};

} // namespace