const API_BASE_URL = '/api';

class ApiService {
    constructor() {
        this.baseUrl = API_BASE_URL;
        this.token = null;
    }

    setToken(token) {
        this.token = token;
    }

    clearToken() {
        this.token = null;
    }

    async request(endpoint, options = {}) {
        const url = `${this.baseUrl}${endpoint}`;
        
        const headers = {
            'Content-Type': 'application/json',
            ...options.headers
        };
        
        if (this.token) {
            headers['Authorization'] = `Bearer ${this.token}`;
        }
        
        try {
            const response = await fetch(url, {
                ...options,
                headers
            });
            
            if (!response.ok) {
                const error = await response.json().catch(() => ({}));
                throw new ApiError(response.status, error.message || 'Request failed', error);
            }
            
            if (response.status === 204) {
                return null;
            }
            
            return await response.json();
        } catch (error) {
            if (error instanceof ApiError) throw error;
            throw new ApiError(0, 'Network error', { originalError: error });
        }
    }

    async get(endpoint, params = {}) {
        const queryString = new URLSearchParams(params).toString();
        const url = queryString ? `${endpoint}?${queryString}` : endpoint;
        return this.request(url, { method: 'GET' });
    }

    async post(endpoint, data) {
        return this.request(endpoint, {
            method: 'POST',
            body: JSON.stringify(data)
        });
    }

    async put(endpoint, data) {
        return this.request(endpoint, {
            method: 'PUT',
            body: JSON.stringify(data)
        });
    }

    async patch(endpoint, data) {
        return this.request(endpoint, {
            method: 'PATCH',
            body: JSON.stringify(data)
        });
    }

    async delete(endpoint) {
        return this.request(endpoint, { method: 'DELETE' });
    }

    async getListings(params = {}) {
        return this.get('/items/listings', params);
    }

    async getListing(id) {
        return this.get(`/items/listings/${id}`);
    }

    async createListing(data) {
        return this.post('/items/listings', data);
    }

    async updateListing(id, data) {
        return this.patch(`/items/listings/${id}`, data);
    }

    async deleteListing(id) {
        return this.delete(`/items/listings/${id}`);
    }

    async searchListings(query, params = {}) {
        return this.get('/items/listings', { search: query, ...params });
    }

    async getCategories() {
        return this.get('/items/categories');
    }

    async uploadFile(file) {
        const formData = new FormData();
        formData.append('file', file);
        
        const response = await fetch(`${this.baseUrl}/files`, {
            method: 'POST',
            headers: this.token ? { 'Authorization': `Bearer ${this.token}` } : {},
            body: formData
        });
        
        if (!response.ok) {
            throw new ApiError(response.status, 'Upload failed');
        }
        
        return response.json();
    }
}

class ApiError extends Error {
    constructor(status, message, data = {}) {
        super(message);
        this.name = 'ApiError';
        this.status = status;
        this.data = data;
    }
}

export const api = new ApiService();
export { ApiError };