import db from '@/lib/db';
import type { Toy, User } from '@/types';
import { randomUUID } from 'crypto';

// Helper to parse toy data from DB, converting JSON strings back to objects
const parseToy = (toyData: any): Toy => {
  if (!toyData) return null;
  return {
    ...toyData,
    images: toyData.images ? JSON.parse(toyData.images) : [],
    unavailableRanges: toyData.unavailableRanges ? JSON.parse(toyData.unavailableRanges) : [],
    pricePerDay: Number(toyData.pricePerDay),
    ownerAvatarUrl: toyData.ownerAvatarUrl,
    dataAiHint: toyData.category?.toLowerCase() || 'toy'
  };
};

// --- TOY OPERATIONS ---

export function getAllToys(): Toy[] {
  const stmt = db.prepare(`
    SELECT t.*, u.name as ownerName, u.avatarUrl as ownerAvatarUrl
    FROM toys t 
    JOIN users u ON t.ownerId = u.id
  `);
  const toys = stmt.all();
  return toys.map(parseToy);
}

export function getToyById(id: string): Toy | undefined {
  const stmt = db.prepare(`
    SELECT t.*, u.name as ownerName, u.avatarUrl as ownerAvatarUrl
    FROM toys t 
    JOIN users u ON t.ownerId = u.id 
    WHERE t.id = ?
  `);
  const toy = stmt.get(id);
  return toy ? parseToy(toy) : undefined;
}

export function getToysByOwner(ownerId: number): Toy[] {
  const stmt = db.prepare(`
    SELECT t.*, u.name as ownerName, u.avatarUrl as ownerAvatarUrl
    FROM toys t 
    JOIN users u ON t.ownerId = u.id 
    WHERE t.ownerId = ?
  `);
  const toys = stmt.all(ownerId);
  return toys.map(parseToy);
}

export function createToy(toyData: Omit<Toy, 'id' | 'ownerName' | 'ownerAvatarUrl' | 'dataAiHint'>): Toy {
    const id = `toy-${randomUUID()}`;
    const stmt = db.prepare(
        `INSERT INTO toys (id, name, description, category, images, unavailableRanges, ownerId, pricePerDay, location)
         VALUES (@id, @name, @description, @category, @images, @unavailableRanges, @ownerId, @pricePerDay, @location)`
    );

    stmt.run({
        ...toyData,
        id,
        images: JSON.stringify(toyData.images),
        unavailableRanges: JSON.stringify(toyData.unavailableRanges),
    });

    return getToyById(id)!;
}

export function updateToy(toyData: Omit<Toy, 'ownerName' | 'ownerAvatarUrl' | 'dataAiHint'>): Toy {
    const stmt = db.prepare(
        `UPDATE toys SET
            name = @name,
            description = @description,
            category = @category,
            images = @images,
            unavailableRanges = @unavailableRanges,
            pricePerDay = @pricePerDay,
            location = @location
        WHERE id = @id AND ownerId = @ownerId` // Security check
    );

    const result = stmt.run({
        ...toyData,
        images: JSON.stringify(toyData.images),
        unavailableRanges: JSON.stringify(toyData.unavailableRanges),
    });

    if (result.changes === 0) {
        throw new Error("Toy not found or user not authorized to update.");
    }

    return getToyById(toyData.id)!;
}

export function getOwnerProfile(ownerId: number): User | undefined {
    return getUserById(ownerId);
}

// --- USER OPERATIONS ---

export function getAllUsers(): User[] {
  const stmt = db.prepare('SELECT id, name, nickname, email, role, avatarUrl, bio FROM users');
  return stmt.all() as User[];
}

export function getUserById(id: number): User | undefined {
  const stmt = db.prepare('SELECT * FROM users WHERE id = ?');
  return stmt.get(id) as User | undefined;
}