#include "ui/root_layout.h"
#include "ui/events.h"
#include "esp_log.h"
#include "esp_event.h"

#define TAG "RootLayout"

#define HEADER_HEIGHT 40
#define NAV_BAR_HEIGHT 50

RootLayout::~RootLayout() {
  deinit();
}

esp_err_t RootLayout::init(lv_obj_t* parent, UIHandler* ui_handler) {

  // Configure parent as flexbox column layout
  lv_obj_set_flex_flow(parent, LV_FLEX_FLOW_COLUMN);
  lv_obj_set_flex_align(parent, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_START);
  lv_obj_set_style_pad_all(parent, 0, 0);
  lv_obj_set_style_pad_gap(parent, 0, 0);
  //
  // Create header (top, fixed height)
  header_obj_ = lv_obj_create(parent);
  lv_obj_set_width(header_obj_, lv_pct(100));
  lv_obj_set_height(header_obj_, HEADER_HEIGHT);
  lv_obj_set_style_bg_color(header_obj_, lv_color_white(), 0);
  lv_obj_set_style_border_width(header_obj_, 0, 0);
  lv_obj_set_style_border_color(header_obj_, lv_color_black(), 0);
  lv_obj_set_style_border_width(header_obj_, 1, LV_BORDER_SIDE_BOTTOM);
  lv_obj_set_style_pad_all(header_obj_, 0, 0);
  lv_obj_set_style_radius(header_obj_, 0, 0);
  //
  header_label_ = lv_label_create(header_obj_);
  lv_label_set_text(header_label_, "App");
  lv_obj_set_style_text_color(header_label_, lv_color_black(), 0);
  lv_obj_align(header_label_, LV_ALIGN_LEFT_MID, 10, 0);
  //
  // Create app container (middle, flexible height)
  app_container_ = lv_obj_create(parent);
  lv_obj_set_width(app_container_, lv_pct(100));
  lv_obj_set_flex_grow(app_container_, 1);
  lv_obj_set_style_bg_color(app_container_, lv_color_white(), 0);
  lv_obj_set_style_border_width(app_container_, 0, 0);
  lv_obj_set_style_pad_all(app_container_, 0, 0);
  lv_obj_set_style_radius(app_container_, 0, 0);

  //
  // Create navigation bar (bottom, fixed height)
  nav_bar_obj_ = lv_obj_create(parent);
  lv_obj_set_width(nav_bar_obj_, lv_pct(100));
  lv_obj_set_height(nav_bar_obj_, NAV_BAR_HEIGHT);
  lv_obj_set_style_bg_color(nav_bar_obj_, lv_color_white(), 0);
  lv_obj_set_style_border_color(nav_bar_obj_, lv_color_black(), 0);
  lv_obj_set_style_border_width(nav_bar_obj_, 1, LV_BORDER_SIDE_TOP);
  lv_obj_set_style_pad_all(nav_bar_obj_, 5, 0);
  lv_obj_set_style_radius(nav_bar_obj_, 0, 0);


  // Create back button (aligned to start by flex layout)
  back_button_ = lv_btn_create(nav_bar_obj_);
  lv_obj_set_size(back_button_, 60, NAV_BAR_HEIGHT - 10);
  lv_obj_set_style_bg_color(back_button_, lv_color_white(), 0);
  lv_obj_add_flag(back_button_, LV_OBJ_FLAG_HIDDEN);
  lv_obj_t* back_label = lv_label_create(back_button_);
  lv_label_set_text(back_label, LV_SYMBOL_LEFT);

  // Create home button (aligned to end by flex layout)
  home_button_ = lv_btn_create(nav_bar_obj_);
  lv_obj_set_size(home_button_, 60, NAV_BAR_HEIGHT - 10);
  lv_obj_set_style_bg_color(home_button_, lv_color_white(), 0);
  lv_obj_t* home_label = lv_label_create(home_button_);
  lv_label_set_text(home_label, LV_SYMBOL_HOME);
  lv_obj_set_style_text_color(home_label, lv_color_black(), 0);
  lv_obj_align(home_label, LV_ALIGN_CENTER, 0, 0);

  // Register keyboard event handler
  esp_err_t err = esp_event_handler_instance_register(
    UI_EVENT_BASE,
    ESP_EVENT_ANY_ID,
    [](void* handler_args, esp_event_base_t base, int32_t id, void* event_data) {
      RootLayout* root_layout = static_cast<RootLayout*>(handler_args);
      root_layout->on_keyboard_event_(handler_args, base, id, event_data);
    },
    this,
    &keyboard_event_handler_instance_
  );
  if (err != ESP_OK) {
    ESP_LOGE(TAG, "Failed to register keyboard event handler: %s", esp_err_to_name(err));
  }

  ESP_LOGI(TAG, "Layout created with flexible design: Header=%d, NavBar=%d",
    HEADER_HEIGHT, NAV_BAR_HEIGHT);

  return ESP_OK;
}

esp_err_t RootLayout::deinit(void) {
  // Unregister keyboard event handler
  if (keyboard_event_handler_instance_) {
    esp_event_handler_instance_unregister(
      UI_EVENT_BASE,
      ESP_EVENT_ANY_ID,
      keyboard_event_handler_instance_
    );
    keyboard_event_handler_instance_ = nullptr;
  }

  header_obj_ = nullptr;
  header_label_ = nullptr;
  //
  app_container_ = nullptr;
  //
  nav_bar_obj_ = nullptr;
  back_button_ = nullptr;
  home_button_ = nullptr;

  return ESP_OK;
}

void RootLayout::hide_nav_bar(void) const {
  if (nav_bar_obj_) {
    lv_obj_add_flag(nav_bar_obj_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Navigation bar not initialized");
  }
}

void RootLayout::show_nav_bar(void) const {
  if (nav_bar_obj_) {
    lv_obj_clear_flag(nav_bar_obj_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Navigation bar not initialized");
  }
}

void RootLayout::show_back_button(void) const {
  if (back_button_) {
    lv_obj_clear_flag(back_button_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Back button not initialized");
  }
}

void RootLayout::show_home_button(void) const {
  if (home_button_) {
    lv_obj_clear_flag(home_button_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Home button not found in navigation bar");
  }
}

void RootLayout::hide_back_button(void) const {
  if (back_button_) {
    lv_obj_add_flag(back_button_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Back button not initialized");
  }
}

void RootLayout::hide_home_button(void) const {
  if (home_button_) {
    lv_obj_add_flag(home_button_, LV_OBJ_FLAG_HIDDEN);
  } else {
    ESP_LOGW(TAG, "Home button not found in navigation bar");
  }
}

esp_err_t RootLayout::register_back_button_callback(lv_event_cb_t callback, void* user_data, lv_event_dsc_t** out_event_dsc) const {
  if (!back_button_) {
    ESP_LOGE(TAG, "Back button not initialized");
    return ESP_ERR_INVALID_STATE;
  }
  if (!callback) {
    ESP_LOGE(TAG, "Invalid argument: callback is nullptr");
    return ESP_ERR_INVALID_ARG;
  }
  if (out_event_dsc == nullptr) {
    ESP_LOGE(TAG, "Invalid argument: out_event_dsc is nullptr");
    return ESP_ERR_INVALID_ARG;
  }

  *out_event_dsc = lv_obj_add_event_cb(back_button_, callback, LV_EVENT_CLICKED, user_data);

  if (*out_event_dsc == nullptr) {
    ESP_LOGE(TAG, "Failed to register back button callback");
    return ESP_FAIL;
  }

  return ESP_OK;
}

esp_err_t RootLayout::register_home_button_callback(lv_event_cb_t callback, void* user_data, lv_event_dsc_t** out_event_dsc) const {
  if (!home_button_) {
    ESP_LOGE(TAG, "Home button not found in navigation bar");
    return ESP_ERR_NOT_FOUND;
  }
  if (!callback) {
    ESP_LOGE(TAG, "Invalid argument: callback is nullptr");
    return ESP_ERR_INVALID_ARG;
  }
  if (out_event_dsc == nullptr) {
    ESP_LOGE(TAG, "Invalid argument: out_event_dsc is nullptr");
    return ESP_ERR_INVALID_ARG;
  }

  *out_event_dsc = lv_obj_add_event_cb(home_button_, callback, LV_EVENT_CLICKED, user_data);

  if (*out_event_dsc == nullptr) {
    ESP_LOGE(TAG, "Failed to register home button callback");
    return ESP_FAIL;
  }

  return ESP_OK;
}

esp_err_t RootLayout::update_header(const std::string& title) const {
  if (!header_label_) {
    return ESP_ERR_INVALID_STATE;
  }

  if (title.empty() == false) {
    lv_label_set_text(header_label_, title.c_str());
  } else {
    lv_label_set_text(header_label_, "App");
  }

  return ESP_OK;
}

void RootLayout::on_keyboard_event_(void* handler_args, esp_event_base_t base, int32_t id, void* event_data) {
  if (base != UI_EVENT_BASE) {
    return;
  }

  switch (id) {
    case UI_EVENT_KEYBOARD_SHOWN:
      hide_nav_bar();
      break;

    case UI_EVENT_KEYBOARD_HIDDEN:
      show_nav_bar();
      break;

    default:
      ESP_LOGW(TAG, "Unknown keyboard event ID: %ld", id);
      break;
  }
}