// gKeyMapper - GTK4 GUI for remapping the G keys (G1-G9) of the Logitech G910.
// GUI only for now. Mappings are stored as a simple text file.

#include <gtk/gtk.h>

#include <iostream>
#include <locale.h>
#include <glib/gi18n.h>
#include <string>
#include <vector>

#include "capturedialog.h"
#include "daemonclient.h"
#include "ipc_ids.h"
#include "keyrow.h"
#include "mapping.h"
#include "mappings.h"

#ifndef PACKAGE
#define PACKAGE "gkeymapper"
#endif

#ifndef LOCALEDIR
#define LOCALEDIR "/usr/local/share/locale"
#endif

namespace {

using gkeymapper::KeyRow;
using gkeymapper::kNumKeys;

std::vector<KeyRow> rows;

// Footer view of the daemon. It is filled by the asynchronous callbacks of
// DaemonClient, which arrive on the GTK main loop, so nothing here ever waits
// for the daemon.
struct DaemonFooter {
    bool reachable = false;
    std::string device;
    std::string lastKey;
} daemonFooter;

GtkWidget* daemonLabel = nullptr;
gkeymapper::DaemonClient daemonClient;

// Rebuilds the footer line from the state above. " · " is a separator, not a
// sentence, so it is not translated.
static void refresh_footer() {
    if (daemonLabel == nullptr) {
        return;
    }
    std::string text;
    if (!daemonFooter.reachable) {
        text = _("Daemon: not reachable");
    } else {
        text = _("Daemon: running");
        if (!daemonFooter.device.empty()) {
            g_autofree gchar* device =
                g_strdup_printf(_("Device: %s"), daemonFooter.device.c_str());
            text += " · ";
            text += device;
        }
        if (!daemonFooter.lastKey.empty()) {
            text += " · ";
            text += daemonFooter.lastKey;
        }
    }
    gtk_label_set_text(GTK_LABEL(daemonLabel), text.c_str());
}

static void on_daemon_status(const gkeymapper::DaemonStatus& status) {
    daemonFooter.reachable = status.reachable;
    daemonFooter.device = status.device;
    if (!status.reachable) {
        daemonFooter.lastKey.clear(); // stale once the daemon is gone
    }
    refresh_footer();
}

static void on_daemon_key(int index, const std::string& action) {
    g_autofree gchar* text =
        g_strdup_printf(_("Last key: G%d → %s"), index + 1, action.c_str());
    daemonFooter.lastKey = text;
    refresh_footer();
}

static void on_pick_file_response(GtkDialog* dialog, int response, gpointer userData) {
    if (response == GTK_RESPONSE_ACCEPT) {
        KeyRow* row = static_cast<KeyRow*>(userData);
        GtkFileChooser* chooser = GTK_FILE_CHOOSER(dialog);
        g_autoptr(GFile) file = gtk_file_chooser_get_file(chooser);
        char* path = g_file_get_path(file);
        if (path) {
            gtk_editable_set_text(GTK_EDITABLE(row->targetEntry), path);
            g_free(path);
        }
    }
    gtk_window_destroy(GTK_WINDOW(dialog));
}

static void pick_command_file(KeyRow* row, GtkWindow* parent) {
    GtkWidget* dialog = gtk_file_chooser_dialog_new(_("Choose file"),
                                                   parent,
                                                   GTK_FILE_CHOOSER_ACTION_OPEN,
                                                   _("_Cancel"), GTK_RESPONSE_CANCEL,
                                                   _("_Open"), GTK_RESPONSE_ACCEPT,
                                                   NULL);
    g_signal_connect(dialog, "response", G_CALLBACK(on_pick_file_response), row);
    gtk_window_present(GTK_WINDOW(dialog));
}

void on_capture_clicked(GtkButton* btn, gpointer userData) {
    auto* row = static_cast<KeyRow*>(userData);
    guint sel = gtk_drop_down_get_selected(GTK_DROP_DOWN(row->typeDrop));

    GtkWindow* window = GTK_WINDOW(gtk_widget_get_root(GTK_WIDGET(btn)));
    if (sel == 1) {
        pick_command_file(row, window);
        return;
    }

    if (sel == 0) {
        gkeymapper::open_key_capture_dialog(row, window);
    }
}

static void update_row_state(KeyRow* row) {
    guint sel = gtk_drop_down_get_selected(GTK_DROP_DOWN(row->typeDrop));
    gboolean enabled = (sel != 2);
    gtk_widget_set_sensitive(row->targetEntry, enabled);
    gtk_widget_set_sensitive(row->captureButton, enabled);

    if (sel == 1) {
        gtk_button_set_label(GTK_BUTTON(row->captureButton), _("Choose file..."));
        gtk_entry_set_placeholder_text(GTK_ENTRY(row->targetEntry),
                                       _("e.g. /usr/bin/firefox or custom command"));
    } else {
        gtk_button_set_label(GTK_BUTTON(row->captureButton), _("Capture"));
        gtk_entry_set_placeholder_text(GTK_ENTRY(row->targetEntry),
                                       _("e.g. ctrl+c, ctrl+v"));
    }
    gtk_widget_set_size_request(row->captureButton, 180, -1);
}

static void on_type_changed(GObject* /*object*/, GParamSpec* /*pspec*/, gpointer userData) {
    update_row_state(static_cast<KeyRow*>(userData));
}

void on_save_clicked(GtkButton* /*btn*/, gpointer /*userData*/) {
    const std::string path = gkeymapper::default_config_path();
    g_autofree gchar* dir = g_path_get_dirname(path.c_str());
    g_mkdir_with_parents(dir, 0755);

    if (!gkeymapper::write_mappings(path, rows)) {
        g_printerr(_("Could not save %s.\n"), path.c_str());
        return;
    }

    // Best effort: the daemon would pick the save up through its file watch
    // within about half a second, this just applies it right away.
    daemonClient.reload();

    std::cout << _("Mappings saved to ") << path << "\n";
}

static void on_export_response(GtkDialog* dialog, int response, gpointer /*userData*/) {
    if (response == GTK_RESPONSE_ACCEPT) {
        GtkFileChooser* chooser = GTK_FILE_CHOOSER(dialog);
        g_autoptr(GFile) file = gtk_file_chooser_get_file(chooser);
        char* path = g_file_get_path(file);
        if (path) {
            if (!gkeymapper::write_mappings(path, rows)) {
                g_printerr(_("Could not export mappings.\n"));
            }
            g_free(path);
        }
    }
    gtk_window_destroy(GTK_WINDOW(dialog));
}

static void on_import_response(GtkDialog* dialog, int response, gpointer /*userData*/) {
    if (response == GTK_RESPONSE_ACCEPT) {
        GtkFileChooser* chooser = GTK_FILE_CHOOSER(dialog);
        g_autoptr(GFile) file = gtk_file_chooser_get_file(chooser);
        char* path = g_file_get_path(file);
        if (path) {
            gkeymapper::read_mappings(path, rows);
            g_free(path);
        }
    }
    gtk_window_destroy(GTK_WINDOW(dialog));
}

static std::string find_asset(const std::string& name);

// The icons are compiled into the executable (data/icons.gresource.xml), so the
// GUI has them even when no assets are installed. The file lookup stays as a
// fallback for a build without the resource; because the resource is embedded,
// it wins over any installed file.
static const char* kIconResource = "/dev/rager/gkeymapper/icon.png";
static const char* kIconThemeResource = "/dev/rager/gkeymapper/icons";

static bool have_embedded_icon() {
    return g_resources_get_info(kIconResource, G_RESOURCE_LOOKUP_FLAGS_NONE, nullptr, nullptr,
                                nullptr);
}

static GtkWidget* make_icon_image(int pixelSize) {
    GtkWidget* image = have_embedded_icon()
                           ? gtk_image_new_from_resource(kIconResource)
                           : gtk_image_new_from_file(find_asset("icon.png").c_str());
    gtk_image_set_pixel_size(GTK_IMAGE(image), pixelSize);
    return image;
}

static void show_about_dialog(GtkWindow* parent) {
    GtkWidget* dialog = gtk_about_dialog_new();
    gtk_about_dialog_set_program_name(GTK_ABOUT_DIALOG(dialog), _("gKeyMapper"));
    gtk_about_dialog_set_version(GTK_ABOUT_DIALOG(dialog), gkeymapper::ipc::kVersion);
    gtk_about_dialog_set_comments(GTK_ABOUT_DIALOG(dialog),
                                 _("G-Key mapper for the Logitech G910 (GTK4)."));
    gtk_about_dialog_set_website(GTK_ABOUT_DIALOG(dialog), "https://rager.dev");
    gtk_about_dialog_set_website_label(GTK_ABOUT_DIALOG(dialog), "Thomas Rager - rager.dev");

    GdkTexture* texture = nullptr;
    if (have_embedded_icon()) {
        texture = gdk_texture_new_from_resource(kIconResource);
    } else {
        std::string iconPath = find_asset("icon.png");
        GError* error = nullptr;
        texture = gdk_texture_new_from_filename(iconPath.c_str(), &error);
        if (!texture && error) {
            g_printerr("Could not load icon: %s\n", error->message);
            g_error_free(error);
        }
    }
    if (texture) {
        gtk_about_dialog_set_logo(GTK_ABOUT_DIALOG(dialog), GDK_PAINTABLE(texture));
        g_object_unref(texture);
    }
    gtk_window_set_transient_for(GTK_WINDOW(dialog), parent);
    g_signal_connect(dialog, "response", G_CALLBACK(gtk_window_destroy), NULL);
    gtk_window_present(GTK_WINDOW(dialog));
}

static void do_export(GtkWindow* parent) {
    GtkWidget* dialog = gtk_file_chooser_dialog_new(_("Export configuration"),
                                                   parent,
                                                   GTK_FILE_CHOOSER_ACTION_SAVE,
                                                   _("_Cancel"), GTK_RESPONSE_CANCEL,
                                                   _("_Save"), GTK_RESPONSE_ACCEPT,
                                                   NULL);
    gtk_file_chooser_set_current_name(GTK_FILE_CHOOSER(dialog), "gkeymapper.conf");
    g_signal_connect(dialog, "response", G_CALLBACK(on_export_response), NULL);
    gtk_window_present(GTK_WINDOW(dialog));
}

static void do_import(GtkWindow* parent) {
    GtkWidget* dialog = gtk_file_chooser_dialog_new(_("Import configuration"),
                                                   parent,
                                                   GTK_FILE_CHOOSER_ACTION_OPEN,
                                                   _("_Cancel"), GTK_RESPONSE_CANCEL,
                                                   _("_Open"), GTK_RESPONSE_ACCEPT,
                                                   NULL);
    g_signal_connect(dialog, "response", G_CALLBACK(on_import_response), NULL);
    gtk_window_present(GTK_WINDOW(dialog));
}

static void action_export(GSimpleAction* /*action*/, GVariant* /*parameter*/, gpointer userData) {
    GtkApplication* app = GTK_APPLICATION(userData);
    GtkWindow* window = gtk_application_get_active_window(app);
    if (window) {
        do_export(window);
    }
}

static void action_import(GSimpleAction* /*action*/, GVariant* /*parameter*/, gpointer userData) {
    GtkApplication* app = GTK_APPLICATION(userData);
    GtkWindow* window = gtk_application_get_active_window(app);
    if (window) {
        do_import(window);
    }
}

static void action_about(GSimpleAction* /*action*/, GVariant* /*parameter*/, gpointer userData) {
    GtkApplication* app = GTK_APPLICATION(userData);
    GtkWindow* window = gtk_application_get_active_window(app);
    if (window) {
        show_about_dialog(window);
    }
}

static std::string find_asset(const std::string& name) {
    const char* env = g_getenv("GKEYMAPPER_ASSETS_DIR");
    if (env && *env) {
        std::string path = std::string(env) + "/" + name;
        if (g_file_test(path.c_str(), G_FILE_TEST_EXISTS)) {
            return path;
        }
    }

    std::string local = std::string("./assets/") + name;
    if (g_file_test(local.c_str(), G_FILE_TEST_EXISTS)) {
        return local;
    }

#ifndef ASSETS_DIR
#define ASSETS_DIR "/usr/local/share/gkeymapper/assets"
#endif
    std::string installed = std::string(ASSETS_DIR) + "/" + name;
    if (g_file_test(installed.c_str(), G_FILE_TEST_EXISTS)) {
        return installed;
    }
    return local;
}

void build_ui(GtkApplication* app) {
    GtkWidget* window = gtk_application_window_new(app);
    gtk_window_set_title(GTK_WINDOW(window), _("gKeyMapper – Logitech G910"));
    gtk_window_set_resizable(GTK_WINDOW(window), FALSE);

    GtkWidget* headerBar = gtk_header_bar_new();
    gtk_window_set_titlebar(GTK_WINDOW(window), headerBar);
    // Serve "gkeymapper" from the embedded icons, so the window icon resolves
    // even without an installed hicolor theme.
    gtk_icon_theme_add_resource_path(
        gtk_icon_theme_get_for_display(gtk_widget_get_display(window)), kIconThemeResource);
    gtk_window_set_icon_name(GTK_WINDOW(window), "gkeymapper");

    GtkWidget* titleBox = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 8);
    GtkWidget* iconImage = make_icon_image(24);
    gtk_image_set_pixel_size(GTK_IMAGE(iconImage), 24);
    gtk_box_append(GTK_BOX(titleBox), iconImage);
    gtk_box_append(GTK_BOX(titleBox), gtk_label_new(_("gKeyMapper")));
    gtk_header_bar_set_title_widget(GTK_HEADER_BAR(headerBar), titleBox);

    GMenu* menu = g_menu_new();
    g_menu_append(menu, _("Export configuration..."), "app.export-config");
    g_menu_append(menu, _("Import configuration..."), "app.import-config");

    GMenu* helpSection = g_menu_new();
    g_menu_append(helpSection, _("About"), "app.about");
    g_menu_append_section(menu, NULL, G_MENU_MODEL(helpSection));

    GtkWidget* menuButton = gtk_menu_button_new();
    gtk_menu_button_set_icon_name(GTK_MENU_BUTTON(menuButton), "open-menu-symbolic");
    gtk_menu_button_set_menu_model(GTK_MENU_BUTTON(menuButton), G_MENU_MODEL(menu));
    gtk_header_bar_pack_end(GTK_HEADER_BAR(headerBar), menuButton);

    GtkWidget* outer = gtk_box_new(GTK_ORIENTATION_VERTICAL, 0);
    gtk_window_set_child(GTK_WINDOW(window), outer);

    // Subtitle only: the app name is already in the header bar, and the heading
    // spelled it differently ("G-Key Mapper") on top of that.
    GtkWidget* subtitle =
        gtk_label_new(_("G1 to G9 of the Logitech G910 remapped to keys or commands"));
    gtk_label_set_xalign(GTK_LABEL(subtitle), 0.0f);
    gtk_widget_add_css_class(subtitle, "dim-label");
    gtk_widget_set_margin_top(subtitle, 16);
    gtk_widget_set_margin_bottom(subtitle, 8);
    gtk_widget_set_margin_start(subtitle, 16);
    gtk_widget_set_margin_end(subtitle, 16);
    gtk_box_append(GTK_BOX(outer), subtitle);

    // Table with all nine G keys (no scrolling needed, everything stays visible)
    GtkWidget* grid = gtk_grid_new();
    gtk_grid_set_row_spacing(GTK_GRID(grid), 6);
    gtk_grid_set_column_spacing(GTK_GRID(grid), 8);
    gtk_widget_set_margin_top(grid, 8);
    gtk_widget_set_margin_bottom(grid, 4);
    gtk_widget_set_margin_start(grid, 16);
    gtk_widget_set_margin_end(grid, 16);
    gtk_widget_set_hexpand(grid, TRUE);
    gtk_box_append(GTK_BOX(outer), grid);

    // Column headers
    const char* headers[] = { _("G-Key"), _("Type"), _("Target (Key/Command)"), _("Action") };
    for (int c = 0; c < 4; ++c) {
        GtkWidget* h = gtk_label_new(nullptr);
        g_autofree gchar* headerMarkup = g_strdup_printf("<b>%s</b>", headers[c]);
        gtk_label_set_markup(GTK_LABEL(h), headerMarkup);
        gtk_widget_add_css_class(h, "dim-label");
        gtk_grid_attach(GTK_GRID(grid), h, c, 0, 1, 1);
    }

    const char* typeOptions[] = { _("Key"), _("Command"), _("Disabled"), nullptr };

    rows.resize(kNumKeys);
    for (int i = 0; i < kNumKeys; ++i) {
        rows[i].index = i;

        // G key label
        GtkWidget* keyLabel = gtk_label_new(nullptr);
        g_autofree gchar* keyMarkup = g_strdup_printf("<b>G%d</b>", i + 1);
        gtk_label_set_markup(GTK_LABEL(keyLabel), keyMarkup);
        gtk_grid_attach(GTK_GRID(grid), keyLabel, 0, i + 1, 1, 1);
        rows[i].keyLabel = keyLabel;

        // Type dropdown (fixed width so rows don't jump between languages)
        GtkWidget* drop = gtk_drop_down_new_from_strings(typeOptions);
        gtk_drop_down_set_selected(GTK_DROP_DOWN(drop), 0);
        gtk_widget_set_size_request(drop, 150, -1);
        gtk_grid_attach(GTK_GRID(grid), drop, 1, i + 1, 1, 1);
        rows[i].typeDrop = drop;

        g_signal_connect(drop, "notify::selected", G_CALLBACK(on_type_changed), &rows[i]);

        // Target input (wide: commands and file paths need room)
        GtkWidget* entry = gtk_entry_new();
        gtk_entry_set_placeholder_text(GTK_ENTRY(entry), _("e.g. ctrl+c, ctrl+v"));
        gtk_widget_set_size_request(entry, 440, -1);
        gtk_widget_set_hexpand(entry, TRUE);
        gtk_grid_attach(GTK_GRID(grid), entry, 2, i + 1, 1, 1);
        rows[i].targetEntry = entry;

        // Capture button
        GtkWidget* capture = gtk_button_new_with_label(_("Capture"));
        gtk_widget_set_size_request(capture, 180, -1);
        g_signal_connect(capture, "clicked", G_CALLBACK(on_capture_clicked), &rows[i]);
        gtk_grid_attach(GTK_GRID(grid), capture, 3, i + 1, 1, 1);
        rows[i].captureButton = capture;

        update_row_state(&rows[i]);
    }

    // Footer with save button and the daemon status line
    GtkWidget* footer = gtk_box_new(GTK_ORIENTATION_VERTICAL, 6);
    gtk_widget_set_margin_top(footer, 8);
    gtk_widget_set_margin_bottom(footer, 16);
    gtk_widget_set_margin_start(footer, 16);
    gtk_widget_set_margin_end(footer, 16);
    gtk_box_append(GTK_BOX(outer), footer);

    GtkWidget* footerRow = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 8);
    gtk_box_append(GTK_BOX(footer), footerRow);

    GtkWidget* saveBtn = gtk_button_new_with_label(_("Save mappings"));
    // No "suggested-action" class on purpose: it gets a strong accent color
    // (e.g. Mint-Y green) that clashes with the rest of the layout. The plain
    // button follows the system theme like everything else.
    g_signal_connect(saveBtn, "clicked", G_CALLBACK(on_save_clicked), nullptr);
    gtk_box_append(GTK_BOX(footerRow), saveBtn);

    GtkWidget* hint = gtk_label_new(_("Saved to ~/.config/gKeyMapper/mappings.conf"));
    gtk_widget_add_css_class(hint, "dim-label");
    gtk_widget_set_halign(hint, GTK_ALIGN_END);
    gtk_widget_set_hexpand(hint, TRUE);
    gtk_box_append(GTK_BOX(footerRow), hint);

    // Daemon status: control plane only, the keypress path never leaves the
    // daemon. Text starts neutral so the footer does not change height when the
    // first reply arrives. Plain label on purpose: GTK4's GtkStatusbar would add
    // a message stack (pop/push) and is exposed over AT-SPI as a generic filler,
    // so it brings no benefit here.
    daemonLabel = gtk_label_new(_("Daemon: checking..."));
    gtk_widget_add_css_class(daemonLabel, "dim-label");
    gtk_label_set_xalign(GTK_LABEL(daemonLabel), 0.0f);
    gtk_label_set_ellipsize(GTK_LABEL(daemonLabel), PANGO_ELLIPSIZE_END);
    gtk_box_append(GTK_BOX(footer), daemonLabel);

    gtk_window_present(GTK_WINDOW(window));

    daemonClient.init(on_daemon_status, on_daemon_key);
}

static void on_activate(GtkApplication* app, gpointer /*user_data*/) {
    GSimpleAction* exportAction = g_simple_action_new("export-config", NULL);
    g_signal_connect(exportAction, "activate", G_CALLBACK(action_export), app);
    g_action_map_add_action(G_ACTION_MAP(app), G_ACTION(exportAction));

    GSimpleAction* importAction = g_simple_action_new("import-config", NULL);
    g_signal_connect(importAction, "activate", G_CALLBACK(action_import), app);
    g_action_map_add_action(G_ACTION_MAP(app), G_ACTION(importAction));

    GSimpleAction* aboutAction = g_simple_action_new("about", NULL);
    g_signal_connect(aboutAction, "activate", G_CALLBACK(action_about), app);
    g_action_map_add_action(G_ACTION_MAP(app), G_ACTION(aboutAction));

    build_ui(app);
}
} // namespace

int main(int argc, char** argv) {
    setlocale(LC_ALL, "");

    const char* localedir = g_getenv("GKEYMAPPER_LOCALEDIR");
    if (!localedir || !*localedir) {
        localedir = LOCALEDIR;
    }
    bindtextdomain(PACKAGE, localedir);
    bind_textdomain_codeset(PACKAGE, "UTF-8");
    textdomain(PACKAGE);

    GtkApplication* app = gtk_application_new(gkeymapper::ipc::kAppId,
                                              G_APPLICATION_FLAGS_NONE);
    g_signal_connect(app, "activate", G_CALLBACK(on_activate), nullptr);
    int status = g_application_run(G_APPLICATION(app), argc, argv);
    g_object_unref(app);
    return status;
}