import { ref, computed } from 'vue';
import { defineStore } from 'pinia';
import type { SnapType } from '../composables/useDraggable';

// Define the shape of a window
export interface WindowState {
  id: string;
  title: string;
  x: number;
  y: number;
  width: number;
  height: number;
  zIndex: number;
  isMinimized: boolean;
  isMaximized: boolean;
  isFocused: boolean;
}

let windowIdCounter = 0;

// Converted to a Setup Store to avoid `this` context issues in SSR.
export const useWindowsStore = defineStore('windows', () => {
  // State
  const windows = ref<WindowState[]>([]);
  const nextZIndex = ref(100);
  const focusedWindowId = ref<string | null>(null);

  // Getters
  const getWindowById = computed(() => {
    return (id: string) => windows.value.find(w => w.id === id);
  });

  const orderedWindows = computed(() => {
    return [...windows.value].sort((a, b) => a.zIndex - b.zIndex);
  });

  // Actions
  function createWindow(title: string = 'New Window') {
    const newId = windowIdCounter++;
    const newWindow: WindowState = {
      id: `window-${newId}`,
      title: `${title} #${newId + 1}`,
      x: Math.random() * 200 + 50,
      y: Math.random() * 100 + 50 + 48, // Adjust initial Y to be below taskbar
      width: 520,
      height: 320,
      zIndex: nextZIndex.value++,
      isMinimized: false,
      isMaximized: false,
      isFocused: true,
    };

    windows.value.forEach(w => w.isFocused = false);
    windows.value.push(newWindow);
    focusedWindowId.value = newWindow.id;
  }

  function focusWindow(id: string) {
    const windowToFocus = windows.value.find(w => w.id === id);
    if (!windowToFocus || windowToFocus.isFocused) return;

    windows.value.forEach(w => { w.isFocused = false; });

    windowToFocus.zIndex = nextZIndex.value++;
    windowToFocus.isFocused = true;
    focusedWindowId.value = id;

    if (windowToFocus.isMinimized) {
      windowToFocus.isMinimized = false;
    }
  }

  function closeWindow(id: string) {
    windows.value = windows.value.filter(w => w.id !== id);
    if (focusedWindowId.value === id) {
      const topWindow = orderedWindows.value[orderedWindows.value.length - 1];
      if (topWindow) {
        focusWindow(topWindow.id);
      } else {
        focusedWindowId.value = null;
      }
    }
  }

  function closeAllWindows() {
    windows.value = [];
    focusedWindowId.value = null;
  }

  function minimizeWindow(id: string) {
    const windowToMinimize = windows.value.find(w => w.id === id);
    if (windowToMinimize) {
      windowToMinimize.isMinimized = true;
      windowToMinimize.isFocused = false;
      const topWindow = orderedWindows.value.filter(w => !w.isMinimized).pop();
      if (topWindow) {
        focusWindow(topWindow.id);
      } else {
        focusedWindowId.value = null;
      }
    }
  }

  function toggleMaximize(id: string) {
    const windowToMaximize = windows.value.find(w => w.id === id);
    if (windowToMaximize) {
      windowToMaximize.isMaximized = !windowToMaximize.isMaximized;
      focusWindow(id);
    }
  }

  function snapWindow(id: string, snapType: SnapType) {
    const windowToSnap = windows.value.find(w => w.id === id);
    if (!windowToSnap) return;

    const taskbarHeight = 22; // Updated taskbar height
    const screenWidth = window.innerWidth;
    const screenHeight = window.innerHeight - taskbarHeight;

    windowToSnap.isMaximized = false; // Always unmaximize when snapping

    switch (snapType) {
      case 'left':
        windowToSnap.x = 0;
        windowToSnap.y = taskbarHeight;
        windowToSnap.width = screenWidth / 2;
        windowToSnap.height = screenHeight;
        break;
      case 'right':
        windowToSnap.x = screenWidth / 2;
        windowToSnap.y = taskbarHeight;
        windowToSnap.width = screenWidth / 2;
        windowToSnap.height = screenHeight;
        break;
      case 'top':
        windowToSnap.x = 0;
        windowToSnap.y = taskbarHeight;
        windowToSnap.width = screenWidth;
        windowToSnap.height = screenHeight;
        break;
    }
    focusWindow(id);
  }

  function updateWindowPosition({ id, x, y }: { id: string; x: number; y: number }) {
    const window = windows.value.find(w => w.id === id);
    if (window && !window.isMaximized) {
      window.x = x;
      window.y = y;
    }
  }

  function updateWindowSize({ id, width, height }: { id: string; width: number; height: number }) {
    const window = windows.value.find(w => w.id === id);
    if (window && !window.isMaximized) {
      window.width = width;
      window.height = height;
    }
  }

  return {
    windows,
    nextZIndex,
    focusedWindowId,
    getWindowById,
    orderedWindows,
    createWindow,
    focusWindow,
    closeWindow,
    closeAllWindows,
    minimizeWindow,
    toggleMaximize,
    snapWindow,
    updateWindowPosition,
    updateWindowSize,
  };
});