import { ref, computed } from 'vue';
import { defineStore } from 'pinia';
import type { AppInfo } from './apps';

export interface DesktopIconPosition {
  appId: string;
  x: number;
  y: number;
}

export const useDesktopStore = defineStore('desktop', () => {
  // Desktop icon positions
  const iconPositions = ref<DesktopIconPosition[]>([]);

  // Default grid positions for new icons
  const getNextGridPosition = () => {
    const iconSize = 80;
    const padding = 20;
    
    // Check if we're in browser environment
    const screenWidth = typeof window !== 'undefined' ? window.innerWidth : 1200;
    const cols = Math.floor((screenWidth - padding) / (iconSize + padding));
    
    const currentCount = iconPositions.value.length;
    const row = Math.floor(currentCount / cols);
    const col = currentCount % cols;
    
    return {
      x: padding + col * (iconSize + padding),
      y: 48 + padding + row * (iconSize + padding) // Below taskbar
    };
  };

  // Initialize desktop icons for available apps
  function initializeDesktopIcons(apps: AppInfo[]) {
    if (iconPositions.value.length === 0) {
      apps.forEach((app, index) => {
        const position = getNextGridPosition();
        iconPositions.value.push({
          appId: app.id,
          x: position.x,
          y: position.y
        });
      });
    }
  }

  // Update icon position
  function updateIconPosition(appId: string, x: number, y: number) {
    const icon = iconPositions.value.find(pos => pos.appId === appId);
    if (icon) {
      icon.x = x;
      icon.y = y;
    }
  }

  // Get icon position
  function getIconPosition(appId: string) {
    return iconPositions.value.find(pos => pos.appId === appId);
  }

  // Add new icon to desktop
  function addIconToDesktop(appId: string) {
    const existing = iconPositions.value.find(pos => pos.appId === appId);
    if (!existing) {
      const position = getNextGridPosition();
      iconPositions.value.push({
        appId,
        x: position.x,
        y: position.y
      });
    }
  }

  // Remove icon from desktop
  function removeIconFromDesktop(appId: string) {
    iconPositions.value = iconPositions.value.filter(pos => pos.appId !== appId);
  }

  // Auto-arrange icons in grid
  function arrangeIconsInGrid() {
    const iconSize = 80;
    const padding = 20;
    const screenWidth = typeof window !== 'undefined' ? window.innerWidth : 1200;
    const cols = Math.floor((screenWidth - padding) / (iconSize + padding));
    
    iconPositions.value.forEach((icon, index) => {
      const row = Math.floor(index / cols);
      const col = index % cols;
      
      icon.x = padding + col * (iconSize + padding);
      icon.y = 48 + padding + row * (iconSize + padding);
    });
  }

  return {
    iconPositions,
    initializeDesktopIcons,
    updateIconPosition,
    getIconPosition,
    addIconToDesktop,
    removeIconFromDesktop,
    arrangeIconsInGrid,
  };
});