import { Injectable } from '@angular/core';
import { Observable, of, delay } from 'rxjs';
import { Project, Category, Subcategory, Item, ItemsListResponse } from '../models';

@Injectable({
  providedIn: 'root'
})
export class MockDataService {
  private projects: Project[] = [
    {
      id: 'dexar',
      name: 'dexar',
      displayName: 'Dexar Marketplace',
      active: true,
      logoUrl: 'https://via.placeholder.com/150?text=Dexar'
    },
    {
      id: 'novo',
      name: 'novo',
      displayName: 'Novo Shop',
      active: true,
      logoUrl: 'https://via.placeholder.com/150?text=Novo'
    }
  ];

  private categories: Category[] = [
    {
      id: 'cat1',
      name: 'Electronics',
      visible: true,
      priority: 1,
      img: 'https://via.placeholder.com/400x300?text=Electronics',
      projectId: 'dexar',
      subcategories: [
        {
          id: 'sub1',
          name: 'Smartphones',
          visible: true,
          priority: 1,
          img: 'https://via.placeholder.com/400x300?text=Smartphones',
          categoryId: 'cat1',
          itemCount: 15
        },
        {
          id: 'sub2',
          name: 'Laptops',
          visible: true,
          priority: 2,
          img: 'https://via.placeholder.com/400x300?text=Laptops',
          categoryId: 'cat1',
          itemCount: 12
        }
      ]
    },
    {
      id: 'cat2',
      name: 'Clothing',
      visible: true,
      priority: 2,
      img: 'https://via.placeholder.com/400x300?text=Clothing',
      projectId: 'dexar',
      subcategories: [
        {
          id: 'sub3',
          name: 'Men',
          visible: true,
          priority: 1,
          img: 'https://via.placeholder.com/400x300?text=Men',
          categoryId: 'cat2',
          itemCount: 25
        }
      ]
    },
    {
      id: 'cat3',
      name: 'Home & Garden',
      visible: false,
      priority: 3,
      img: 'https://via.placeholder.com/400x300?text=Home',
      projectId: 'novo',
      subcategories: []
    }
  ];

  private items: Item[] = [
    {
      id: 'item1',
      name: 'iPhone 15 Pro Max',
      visible: true,
      priority: 1,
      quantity: 50,
      price: 1299,
      currency: 'USD',
      imgs: [
        'https://via.placeholder.com/600x400?text=iPhone+Front',
        'https://via.placeholder.com/600x400?text=iPhone+Back'
      ],
      tags: ['new', 'featured', 'bestseller'],
      simpleDescription: 'Latest iPhone with titanium design and A17 Pro chip',
      description: [
        { key: 'Color', value: 'Natural Titanium' },
        { key: 'Storage', value: '256GB' },
        { key: 'Display', value: '6.7 inch Super Retina XDR' },
        { key: 'Chip', value: 'A17 Pro' }
      ],
      subcategoryId: 'sub1',
      comments: [
        {
          id: 'c1',
          text: 'Great phone! Battery life is amazing.',
          createdAt: new Date('2024-01-10'),
          author: 'John Doe'
        }
      ]
    },
    {
      id: 'item2',
      name: 'Samsung Galaxy S24 Ultra',
      visible: true,
      priority: 2,
      quantity: 35,
      price: 1199,
      currency: 'USD',
      imgs: ['https://via.placeholder.com/600x400?text=Samsung+S24'],
      tags: ['new', 'android'],
      simpleDescription: 'Premium Samsung flagship with S Pen',
      description: [
        { key: 'Color', value: 'Titanium Gray' },
        { key: 'Storage', value: '512GB' },
        { key: 'RAM', value: '12GB' }
      ],
      subcategoryId: 'sub1'
    },
    {
      id: 'item3',
      name: 'Google Pixel 8 Pro',
      visible: true,
      priority: 3,
      quantity: 20,
      price: 999,
      currency: 'USD',
      imgs: ['https://via.placeholder.com/600x400?text=Pixel+8'],
      tags: ['sale', 'android', 'ai'],
      simpleDescription: 'Best AI photography phone',
      description: [
        { key: 'Color', value: 'Bay Blue' },
        { key: 'Storage', value: '256GB' }
      ],
      subcategoryId: 'sub1'
    },
    {
      id: 'item4',
      name: 'MacBook Pro 16"',
      visible: true,
      priority: 1,
      quantity: 15,
      price: 2499,
      currency: 'USD',
      imgs: ['https://via.placeholder.com/600x400?text=MacBook'],
      tags: ['featured', 'professional'],
      simpleDescription: 'Powerful laptop for professionals',
      description: [
        { key: 'Processor', value: 'M3 Max' },
        { key: 'RAM', value: '36GB' },
        { key: 'Storage', value: '1TB SSD' }
      ],
      subcategoryId: 'sub2'
    },
    {
      id: 'item5',
      name: 'Dell XPS 15',
      visible: true,
      priority: 2,
      quantity: 0,
      price: 1799,
      currency: 'USD',
      imgs: ['https://via.placeholder.com/600x400?text=Dell+XPS'],
      tags: ['out-of-stock'],
      simpleDescription: 'Premium Windows laptop',
      description: [
        { key: 'Processor', value: 'Intel Core i9' },
        { key: 'RAM', value: '32GB' }
      ],
      subcategoryId: 'sub2'
    }
  ];

  // Generate more items for testing infinite scroll
  private generateMoreItems(subcategoryId: string, count: number): Item[] {
    const items: Item[] = [];
    for (let i = 6; i <= count + 5; i++) {
      items.push({
        id: `item${i}`,
        name: `Test Product ${i}`,
        visible: Math.random() > 0.3,
        priority: i,
        quantity: Math.floor(Math.random() * 100),
        price: Math.floor(Math.random() * 1000) + 100,
        currency: 'USD',
        imgs: [`https://via.placeholder.com/600x400?text=Product+${i}`],
        tags: ['test'],
        simpleDescription: `This is test product number ${i}`,
        description: [{ key: 'Size', value: 'Medium' }],
        subcategoryId
      });
    }
    return items;
  }

  getProjects(): Observable<Project[]> {
    return of(this.projects).pipe(delay(300));
  }

  getCategories(projectId: string): Observable<Category[]> {
    const cats = this.categories.filter(c => c.projectId === projectId);
    return of(cats).pipe(delay(300));
  }

  getCategory(categoryId: string): Observable<Category> {
    const cat = this.categories.find(c => c.id === categoryId)!;
    return of(cat).pipe(delay(200));
  }

  updateCategory(categoryId: string, data: Partial<Category>): Observable<Category> {
    const cat = this.categories.find(c => c.id === categoryId)!;
    Object.assign(cat, data);
    return of(cat).pipe(delay(300));
  }

  createCategory(projectId: string, data: Partial<Category>): Observable<Category> {
    const newCat: Category = {
      id: `cat${Date.now()}`,
      name: data.name || 'New Category',
      visible: data.visible ?? true,
      priority: data.priority || 99,
      img: data.img,
      projectId,
      subcategories: []
    };
    this.categories.push(newCat);
    return of(newCat).pipe(delay(300));
  }

  deleteCategory(categoryId: string): Observable<void> {
    const index = this.categories.findIndex(c => c.id === categoryId);
    if (index > -1) this.categories.splice(index, 1);
    return of(void 0).pipe(delay(300));
  }

  getSubcategory(subcategoryId: string): Observable<Subcategory> {
    let sub: Subcategory | undefined;
    for (const cat of this.categories) {
      sub = cat.subcategories?.find(s => s.id === subcategoryId);
      if (sub) break;
    }
    return of(sub!).pipe(delay(200));
  }

  updateSubcategory(subcategoryId: string, data: Partial<Subcategory>): Observable<Subcategory> {
    let sub: Subcategory | undefined;
    for (const cat of this.categories) {
      sub = cat.subcategories?.find(s => s.id === subcategoryId);
      if (sub) {
        Object.assign(sub, data);
        break;
      }
    }
    return of(sub!).pipe(delay(300));
  }

  createSubcategory(categoryId: string, data: Partial<Subcategory>): Observable<Subcategory> {
    const cat = this.categories.find(c => c.id === categoryId)!;
    const newSub: Subcategory = {
      id: `sub${Date.now()}`,
      name: data.name || 'New Subcategory',
      visible: data.visible ?? true,
      priority: data.priority || 99,
      img: data.img,
      categoryId,
      itemCount: 0
    };
    if (!cat.subcategories) cat.subcategories = [];
    cat.subcategories.push(newSub);
    return of(newSub).pipe(delay(300));
  }

  deleteSubcategory(subcategoryId: string): Observable<void> {
    for (const cat of this.categories) {
      const index = cat.subcategories?.findIndex(s => s.id === subcategoryId) ?? -1;
      if (index > -1) {
        cat.subcategories?.splice(index, 1);
        break;
      }
    }
    return of(void 0).pipe(delay(300));
  }

  getItems(subcategoryId: string, page = 1, limit = 20, search?: string, filters?: any): Observable<ItemsListResponse> {
    let allItems = [...this.items, ...this.generateMoreItems(subcategoryId, 50)];
    
    // Filter by subcategory
    allItems = allItems.filter(item => item.subcategoryId === subcategoryId);
    
    // Apply search
    if (search) {
      allItems = allItems.filter(item => 
        item.name.toLowerCase().includes(search.toLowerCase())
      );
    }
    
    // Apply visibility filter
    if (filters?.visible !== undefined) {
      allItems = allItems.filter(item => item.visible === filters.visible);
    }
    
    const total = allItems.length;
    const start = (page - 1) * limit;
    const end = start + limit;
    const items = allItems.slice(start, end);
    
    return of({
      items,
      total,
      page,
      limit,
      hasMore: end < total
    }).pipe(delay(400));
  }

  getItem(itemId: string): Observable<Item> {
    const item = this.items.find(i => i.id === itemId)!;
    return of(item).pipe(delay(200));
  }

  updateItem(itemId: string, data: Partial<Item>): Observable<Item> {
    const item = this.items.find(i => i.id === itemId)!;
    Object.assign(item, data);
    return of(item).pipe(delay(300));
  }

  createItem(subcategoryId: string, data: Partial<Item>): Observable<Item> {
    const newItem: Item = {
      id: `item${Date.now()}`,
      name: data.name || 'New Item',
      visible: data.visible ?? true,
      priority: data.priority || 99,
      quantity: data.quantity || 0,
      price: data.price || 0,
      currency: data.currency || 'USD',
      imgs: data.imgs || [],
      tags: data.tags || [],
      simpleDescription: data.simpleDescription || '',
      description: data.description || [],
      subcategoryId
    };
    this.items.push(newItem);
    return of(newItem).pipe(delay(300));
  }

  deleteItem(itemId: string): Observable<void> {
    const index = this.items.findIndex(i => i.id === itemId);
    if (index > -1) this.items.splice(index, 1);
    return of(void 0).pipe(delay(300));
  }

  bulkUpdateItems(itemIds: string[], data: Partial<Item>): Observable<void> {
    itemIds.forEach(id => {
      const item = this.items.find(i => i.id === id);
      if (item) Object.assign(item, data);
    });
    return of(void 0).pipe(delay(400));
  }

  uploadImage(file: File): Observable<{ url: string }> {
    // Simulate upload
    const url = `https://via.placeholder.com/600x400?text=${encodeURIComponent(file.name)}`;
    return of({ url }).pipe(delay(1000));
  }
}