#include <string>
#include "shell.h"
#include "GLOBALS.h"
#include <algorithm>
#include "system_manager.h"
#include "helpers.h"

void Shell::init(TFT_Handler* th, DISPLAY_STATE* ds, SystemManager* system_manager) {
  tft = th;
  display_state = ds;
  _system_manager = system_manager;

  EventManager::getInstance().subscribe(this);

  draw_background(COL_TEAL);
  draw_task_bar(COL_GREY);

  // Create desktop items with their associated program classes
  DesktopItem di0;
  di0.id = 0;
  di0.place_x = 0 * 50 + 1;
  di0.place_y = 10;
  di0.icon_size_x = 45;
  di0.icon_size_y = 50;
  di0.name = "Counter";
  di0.program_class = "CounterProgram";
  items.push_back(di0);

  DesktopItem di1;
  di1.id = 4;
  di1.place_x = 4 * 50 + 1;
  di1.place_y = 10;
  di1.icon_size_x = 45;
  di1.icon_size_y = 50;
  di1.name = "Text Editor";
  di1.program_class = "TextEditorProgram";
  items.push_back(di1);

  DesktopItem di2;
  di2.id = 2;
  di2.place_x = 2 * 50 + 1;
  di2.place_y = 10;
  di2.icon_size_x = 45;
  di2.icon_size_y = 50;
  di2.name = "Calculator";
  di2.program_class = "CalculatorProgram";
  items.push_back(di2);

  DesktopItem di3;
  di3.id = 3;
  di3.place_x = 3 * 50 + 1;
  di3.place_y = 10;
  di3.icon_size_x = 45;
  di3.icon_size_y = 50;
  di3.name = "Game";
  di3.program_class = "Chatty";
  items.push_back(di3);

  DesktopItem di4;
  di4.id = 1;
  di4.place_x = 1 * 50 + 1;
  di4.place_y = 10;
  di4.icon_size_x = 45;
  di4.icon_size_y = 50;
  di4.name = "Settings";
  di4.program_class = "SettingsProgram";
  items.push_back(di4);

  DesktopItem di5;
  di5.id = 5;
  di5.place_x = 5 * 50 + 1;
  di5.place_y = 10;
  di5.icon_size_x = 45;
  di5.icon_size_y = 50;
  di5.name = "Internet Tester";
  di5.program_class = "InternetTester";
  items.push_back(di5);

  for (const auto& item : items) {
    draw_desktop_Item(item);
  }
}

void Shell::on_click_event(CLICK_EVENT event) {
  if (event.event != CLICK_EVENTS::LEFT_CLICK) return;

  // Always check windows first
  short window_id = handle_window_click(event);
  if (window_id >= 0) {
    display_state->update_display.store(true);
    return;
  }

  short icon_id = handle_desktop_click(event);
  if (icon_id != -1) {
    display_state->update_display.store(true);
    return;
  }

  short tast_icon_id = handle_taskbar_click(event);
  if (tast_icon_id != -1) {
    display_state->update_display.store(true);
    return;
  }

  bool ckicked_start_button = handle_start_button_click(event);
  if (ckicked_start_button) {
    display_state->update_display.store(true);
    return;
  }
}

// ======= Window =======
void Shell::create_window(Window* window) {
  short total_pos_x = window->x + window->width;
  short total_pos_y = window->y + window->height;

  // Clamp window within the screen size AND taskbar
  if (total_pos_x > MAX_SCREEN_WIDTH) window->x = MAX_SCREEN_WIDTH - window->width;
  if (total_pos_y > MAX_SCREEN_HEIGHT) window->y = MAX_SCREEN_HEIGHT - window->height - 29;

  windows.push_back(window);

  for (short i = 0; i < task_bar_items.size(); ++i) {
    task_bar_items[i].focused = false;
  }

  TaskBarItem item;
  item.id = window->id;
  item.focused = true;
  item.name = window->title;
  item.width = 95;
  item.height = 18;
  item.offset_x = 100;
  item.place_y = 298;

  // Set place_x and place_y for ALL items
  if (task_bar_items.size() == 0) {
    item.place_x = 60;
  } else {
    // For subsequent items, use the previous item's position + offset
    const TaskBarItem& prev = task_bar_items.back();
    item.place_x = prev.place_x + prev.offset_x;
  }

  task_bar_items.push_back(item);

  display_state->update_display.store(true);
}

void Shell::close_window(short window_id) {
  for (auto it = windows.begin(); it != windows.end(); ++it) {
    if ((*it)->id == window_id) {
      Window* window_to_delete = *it;
      windows.erase(it);
      _system_manager->close_program(window_to_delete->id);
      delete window_to_delete;
      display_state->update_display.store(true);
      break;
    }
  }

  for (auto it = task_bar_items.begin(); it != task_bar_items.end(); ++it) {
    if (it->id == window_id) {
      task_bar_items.erase(it);
      display_state->update_display.store(true);
      break;
    }
  }

  Helpers::recalculate_taskbar(task_bar_items);
}

void Shell::minimize_window(short window_id) {
  for (auto it = windows.begin(); it != windows.end(); ++it) {
    for (short i = 0; i < task_bar_items.size(); ++i) {
      if ((*it)->id == window_id && (*it)->id == task_bar_items[i].id) {
        (*it)->minimized = true;
        task_bar_items[i].focused = false;
        display_state->update_display.store(true);
        break;
      }
    }
  }
}

void Shell::draw_all() {
  draw_background(0x0410);
  draw_task_bar(0xbdf7);

  for (const auto& item : items) {
    draw_desktop_Item(item);
  }

  for (const auto& win : windows) {
    if (win->minimized) continue;
    
    draw_window(*win);
  }
}

void Shell::draw_window(const Window& window) {
  if (window.minimized) return;

  // Outer shadow
  tft->draw_rect(window.x, window.y, window.width + 2, window.height + 2, 1, 0x0000);

  // Inner shadow
  tft->draw_rect(window.x, window.y, window.width + 1, window.height + 1, 1, 0x8410);

  // Highlight
  tft->draw_rect(window.x - 1, window.y - 1, window.width + 1, window.height + 1, 1, 0xffff);

  // Window
  tft->draw_box(window.x, window.y, window.width, window.height, window.background_color);

  // Decorations
  tft->draw_box(window.x + 3, window.y + 3, window.width - 6, 30, window.foreground_color);

  for (auto it = window.window_decorations.begin(); it != window.window_decorations.end(); ++it) {
    if (it->action == WindowAction::CLOSE) {
      // Close button
      tft->draw_box(window.x + it->x_offset, window.y + it->y_offset, it->height, it->width, COL_RED);
    }

    if (it->action == WindowAction::MINIMIZE) {
      // Minimize button
      tft->draw_box(window.x + it->x_offset, window.y + it->y_offset, it->height, it->width, COL_LIGHT_GREY);
    }
  }

  // Window title
  tft->draw_text(window.x + 6 + 65, window.y + 10, window.title, COL_WHITE, 2);

  // Window content
  tft->draw_box(window.x + 3, window.y + 35, window.width - 6, window.height - 38, COL_WHITE);

  for (WindowContentText text : window.window_content_text) {
    tft->draw_text(text.x, text.y, text.text, COL_BLACK, text.size);
  }

  for (ContentButton button : window.content_buttons) {
    tft->draw_button(button.x, button.y, button.width, button.height, COL_GREY, button.pressed, button.action);
  }
}

//  ======= Desktop  =======
void Shell::draw_background(short color) {
  tft->fill_screen(color);
}

void Shell::draw_desktop_Item(const DesktopItem& desktop_item) {
  tft->draw_box(desktop_item.place_x, desktop_item.place_y, desktop_item.icon_size_x, desktop_item.icon_size_y, 0x4648);
}

void Shell::draw_task_bar(short color) {
  // bar
  tft->draw_box(0, 293, 480, 40, color);
  tft->draw_line(0, 294, 480, 294, 0xffff);

  // Outer shadow
  tft->draw_box(5, 297, 53, 21, 0x0000);

  // Inner shadow
  tft->draw_box(6, 298, 51, 19, 0x8410);

  // Highlight
  tft->draw_box(5, 297, 51, 19, 0xffff);

  // Button
  tft->draw_box(6, 298, 50, 18, color);

  for (TaskBarItem item : task_bar_items) {
    if (item.focused) {
      tft->draw_box(item.place_x - 2, item.place_y - 2, item.width + 3, item.height + 3, COL_BLACK);
      tft->draw_box(item.place_x - 1, item.place_y - 1, item.width + 2, item.height + 2, COL_DARK_GREY);
      tft->draw_box(item.place_x, item.place_y, item.width + 2, item.height + 2, COL_WHITE);
      tft->draw_box(item.place_x, item.place_y, item.width, item.height, COL_GREY);

      tft->draw_text(item.place_x + 2, item.place_y + 2, item.name, COL_BLACK, 1);
    } else {
      tft->draw_box(item.place_x - 1, item.place_y - 1, item.width + 1, item.height + 1, COL_WHITE);
      tft->draw_box(item.place_x, item.place_y, item.width + 2, item.height + 2, COL_BLACK);
      tft->draw_rect(item.place_x, item.place_y, item.width + 1, item.height + 1, 1, COL_DARK_GREY);
      tft->draw_box(item.place_x, item.place_y, item.width, item.height, COL_GREY);

      tft->draw_text(item.place_x + 2, item.place_y + 2, item.name, COL_BLACK, 1);
    }
  }
}

void Shell::draw_start_menu() {

}

short Shell::handle_window_click(CLICK_EVENT event) {
  // Iterate BACKWARDS - last window is on top
  for (short i = windows.size() - 1; i >= 0; i--) {
    Window* window = windows[i];
    if (window->minimized) continue;

    // Check if click is within window bounds
    if (event.x >= window->x && event.x <= (window->x + window->width)
    && event.y >= window->y && event.y <= (window->y + window->height)) {

      for (auto it = window->window_decorations.begin(); it != window->window_decorations.end(); ++it) {
        short x = window->x + it->x_offset;
        short y = window->y + it->y_offset;

        // Check if click is within either of the buttons
        if (event.x >= x && event.x <= (x + it->width) && event.y >= y && event.y <= (y + it->height) && it->action == WindowAction::CLOSE && !window->minimized) {
          close_window(window->id);
          return window->id;
        }

        if (event.x >= x && event.x <= (x + it->width) && event.y >= y && event.y <= (y + it->height) && it->action == WindowAction::MINIMIZE) {
          minimize_window(window->id);
          return window->id;
        }
      }

      // Unfocus all windows
      for (auto& win : windows) {
        win->focused = false;
      }

      // Focus this window
      window->focused = true;

      // Move window to end (top of z-order)
      auto it = windows.begin() + i;
      std::rotate(it, it + 1, windows.end());

      return window->id;
    }
  }

  return -1;
}

short Shell::handle_desktop_click(CLICK_EVENT event) {
  for (const auto& item : items) {
    if (event.x >= item.place_x && event.x <= (item.place_x + item.icon_size_x) 
        && event.y >= item.place_y && event.y <= (item.place_y + item.icon_size_y)) {

      // Check if program is already running
      for (const auto& prog : _system_manager->_programs) {
        if (prog->get_name() == item.name) {
          return -1; // Already running
        }
      }

      // Create window
      Window* win = new Window();

      WindowDecoration close_btn = {
        .x_offset = 6,
        .y_offset = 5,
        .width = 25,
        .height = 25,
        .action = WindowAction::CLOSE,
      };

      WindowDecoration minimize_btn = {
        .x_offset = 36,
        .y_offset = 5,
        .width = 25,
        .height = 25,
        .action = WindowAction::MINIMIZE,
      };

      win->window_decorations.push_back(close_btn);
      win->window_decorations.push_back(minimize_btn);

      win->x = 10;
      win->y = 0;
      win->width = 350;
      win->height = 250;
      win->background_color = 0xbdf7;
      win->foreground_color = COL_DARK_BLUE;
      win->focused = true;
      win->minimized = false;
      win->title = item.name;
      win->window_content_text = {};

      // Spawn program using the program_class
      bool result = _system_manager->spawn_program(win, item.program_class);

      if (!result) {
        delete win;
        return -1;
      }

      create_window(win);
      return item.id;
    }
  }

  return -1;
}

short Shell::handle_taskbar_click(CLICK_EVENT event) {
  for (short i = 0; i < task_bar_items.size(); ++i) {
    if (event.x >= task_bar_items[i].place_x && event.x <= (task_bar_items[i].place_x + task_bar_items[i].width) && event.y >= task_bar_items[i].place_y && event.y <= (task_bar_items[i].place_y + task_bar_items[i].height)) {
      for (short j = 0; j < windows.size(); ++j) {
        if (windows[j]->id != task_bar_items[i].id) continue;

        for (short k = 0; k < windows.size(); ++k) windows[k]->focused = false;

        windows[j]->focused = true;
        windows[j]->minimized = false;

        auto it = windows.begin() + j;
        std::rotate(it, it + 1, windows.end());
      }

      for (short l = 0; l < task_bar_items.size(); ++l) task_bar_items[l].focused = false;
      task_bar_items[i].focused = true;
      return task_bar_items[i].id;
    }
  }
  return -1;
}

bool Shell::handle_start_button_click(CLICK_EVENT event) {
  if (event.x >= 6 && event.x <= (6 + 50) && event.y >= 298 && event.y <= (298 + 18)) {
    Serial.println("Taskbar button clicked");

    // TODO: Handle icon click (open window, etc.)
    return true;
  }

  return false;
}