import { ref, computed } from 'vue';
import { defineStore } from 'pinia';

export interface AppInfo {
  id: string;
  name: string;
  icon: string;
  component: string;
  description: string;
  category: string;
}

export interface AppInstance {
  id: string;
  appId: string;
  title: string;
  x: number;
  y: number;
  width: number;
  height: number;
  zIndex: number;
  isMinimized: boolean;
  isMaximized: boolean;
  isFocused: boolean;
}

let appInstanceIdCounter = 0;

export const useAppsStore = defineStore('apps', () => {
  // Available apps registry
  const availableApps = ref<AppInfo[]>([
    {
      id: 'calculator',
      name: 'Calculator',
      icon: '🧮',
      component: 'Calculator',
      description: 'A simple calculator for basic arithmetic operations',
      category: 'Utilities'
    },
    // More apps can be added here in the future
  ]);

  // Running app instances
  const appInstances = ref<AppInstance[]>([]);
  const nextZIndex = ref(100);

  // Getters
  const getAppById = computed(() => {
    return (id: string) => availableApps.value.find(app => app.id === id);
  });

  const getAppInstanceById = computed(() => {
    return (id: string) => appInstances.value.find(instance => instance.id === id);
  });

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

  const focusedAppInstance = computed(() => {
    return appInstances.value.find(instance => instance.isFocused);
  });

  // Actions
  function launchApp(appId: string) {
    const app = getAppById.value(appId);
    if (!app) {
      console.error(`App with id "${appId}" not found`);
      return null;
    }

    const newInstanceId = appInstanceIdCounter++;
    const newInstance: AppInstance = {
      id: `app-${appId}-${newInstanceId}`,
      appId: appId,
      title: `${app.name} #${newInstanceId + 1}`,
      x: Math.random() * 200 + 50,
      y: Math.random() * 100 + 50 + 48, // Below taskbar
      width: 320,
      height: 400,
      zIndex: nextZIndex.value++,
      isMinimized: false,
      isMaximized: false,
      isFocused: true,
    };

    // Unfocus all other instances
    appInstances.value.forEach(instance => instance.isFocused = false);
    
    appInstances.value.push(newInstance);
    return newInstance;
  }

  function focusAppInstance(instanceId: string) {
    const instance = appInstances.value.find(i => i.id === instanceId);
    if (!instance || instance.isFocused) return;

    // Unfocus all other instances
    appInstances.value.forEach(i => i.isFocused = false);

    instance.zIndex = nextZIndex.value++;
    instance.isFocused = true;

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

  function closeAppInstance(instanceId: string) {
    appInstances.value = appInstances.value.filter(i => i.id !== instanceId);
  }

  function minimizeAppInstance(instanceId: string) {
    const instance = appInstances.value.find(i => i.id === instanceId);
    if (instance) {
      instance.isMinimized = true;
      instance.isFocused = false;
    }
  }

  function toggleMaximizeAppInstance(instanceId: string) {
    const instance = appInstances.value.find(i => i.id === instanceId);
    if (instance) {
      instance.isMaximized = !instance.isMaximized;
      focusAppInstance(instanceId);
    }
  }

  function updateAppInstancePosition({ id, x, y }: { id: string; x: number; y: number }) {
    const instance = appInstances.value.find(i => i.id === id);
    if (instance && !instance.isMaximized) {
      instance.x = x;
      instance.y = y;
    }
  }

  function updateAppInstanceSize({ id, width, height }: { id: string; width: number; height: number }) {
    const instance = appInstances.value.find(i => i.id === id);
    if (instance && !instance.isMaximized) {
      instance.width = width;
      instance.height = height;
    }
  }

  function closeAllAppInstances() {
    appInstances.value = [];
  }

  return {
    availableApps,
    appInstances,
    nextZIndex,
    getAppById,
    getAppInstanceById,
    orderedAppInstances,
    focusedAppInstance,
    launchApp,
    focusAppInstance,
    closeAppInstance,
    minimizeAppInstance,
    toggleMaximizeAppInstance,
    updateAppInstancePosition,
    updateAppInstanceSize,
    closeAllAppInstances,
  };
});