import * as SecureStore from 'expo-secure-store';

import {

  User,

  AuthResponse,

  VerifyTokenResponse,

  SignUpPayload,

  ResetPasswordRequestResponse,

  ResetPasswordResponse,

  UserUpdatePayload,

  UserUpdateResponse,

  MoodComponentPayload,

  MoodEntryPayload,

  SleepRecordPayload,

  PaginatedResponse

} from '@/lib/api/types';

const API_BASE_URL = process.env.EXPO_PUBLIC_API_BASE_URL;

const TOKEN_KEY = process.env.EXPO_PUBLIC_TOKEN_KEY;

class ApiClient {

  private async getStoredToken(): Promise<string | null> {

    try {

      return await SecureStore.getItemAsync(TOKEN_KEY);

    } catch (error) {

      console.error('Failed to get stored token:', error);

      return null;

    }

  }

  private async storeToken(token: string): Promise<void> {

    try {

      await SecureStore.setItemAsync(TOKEN_KEY, token);

    } catch (error) {

      console.error('Failed to store token:', error);

      throw error;

    }

  }

  private async removeToken(): Promise<void> {

    try {

      await SecureStore.deleteItemAsync(TOKEN_KEY);

    } catch (error) {

      console.error('Failed to remove token:', error);

    }

  }

  async getStoredAuthData(): Promise<{ token: string | null }> {

    const token = await this.getStoredToken();

    return { token };

  }

  private async request<T>(

    endpoint: string,

    options: RequestInit = {}

  ): Promise<T> {

    const token = await this.getStoredToken();

    const isFormData = options.body instanceof FormData;

    const config: RequestInit = {

      ...options,

      headers: {

        ...(token && { Authorization: `Bearer ${token}` }),

        ...(!isFormData && { 'Content-Type': 'application/json' }),

        ...options.headers,

      },

    };

    const response = await fetch(`${API_BASE_URL}${endpoint}`, config);

    if (!response.ok) {

      const error = await response.json()

        .catch(() => ({ error: 'Network error' }));

      console.error("[API]: ", error, response.status)

      throw new Error(error.error || `HTTP ${response.status}`);

    }

    return response.json();

  }

  // Auth

  async login(email: string, password: string): Promise<AuthResponse> {

    const response = await this.request<AuthResponse>('/auth/login', {

      method: 'POST',

      body: JSON.stringify({ email, password }),

    });

    await this.storeToken(response.token);

    return response;

  }

  async signup(user: SignUpPayload): Promise<AuthResponse> {

    const response = await this.request<AuthResponse>('/users', {

      method: 'POST',

      body: JSON.stringify({ user }),

    });

    await this.storeToken(response.token);

    return response;

  }

  async forgotPassword(email: string): Promise<ResetPasswordRequestResponse> {

    return this.request('/auth/forgot-password', {

      method: 'POST',

      body: JSON.stringify({ email }),

    });

  }

  async resetPassword(token: string, password: string): Promise<ResetPasswordResponse> {

    return this.request('/auth/reset-password', {

      method: 'POST',

      body: JSON.stringify({ token, newPassword: password }),

    });

  }

  async verifyToken(): Promise<VerifyTokenResponse> {

    try {

      return await this.request('/auth/verify');

    } catch (error) {

      // Token is invalid or expired

      await this.removeToken();

      throw error;

    }

  }

  async logout(): Promise<void> {

    await this.removeToken();

  }

  // User-related

  async updateUser(user: UserUpdatePayload): Promise<User> {

    return await this.request(`/users/${user.id}`, {

      method: 'PUT',

      body: JSON.stringify({ user })

    })

  }

  async avatar(formData: FormData): Promise<User> {

    return await this.request(`/users/me/avatar`, {

      method: 'POST',

      body: formData,

      headers: {

        'Content-Type': 'multipart/form-data',

      } as any,

    })

  }

  async removeAvatar(): Promise<void> {

    return await this.request(`/users/me/avatar`, {

      method: 'DELETE'

    });

  }

  // Mood-related

  async createMoodEntry(mood: CreateMoodEntryPayload): Promise<MoodEntryResponse> {

    return await this.request(`/moods`, {

      method: 'POST',

      body: JSON.stringify({ mood })

    })

  }

  async getMoodEntries(params?: {

    from?: string;

    to?: string;

    page?: number;

    limit?: number;

  }): Promise<PaginatedResponse<MoodEntry>> {

    const query = new URLSearchParams();

    if (params?.from)  query.set('from', params.from);

    if (params?.to)    query.set('to', params.to);

    if (params?.page)  query.set('page', String(params.page));

    if (params?.limit) query.set('limit', String(params.limit));

    const qs = query.toString();

    return this.request(`/moods${qs ? `?${qs}` : ''}`);

  }

  async getMoodEntry(id: string): Promise<MoodEntry> {

    return this.request(`/moods/${id}`);

  }

  async deleteMoodEntry(id: string): Promise<void> {

    return this.request(`/moods/${id}`, { method: 'DELETE' });

  }

  // Sleep Record

  async createSleepRecord(sleepRecord: CreateSleepRecordPayload): Promise<SleepRecordResponse> {

    return await this.request(`/sleep_records`, {

      method: 'POST',

      body: JSON.stringify({ sleepRecord })

    })

  }

  async getSleepRecords(params?: {

    from?: string;

    to?: string;

    page?: number;

    limit?: number;

  }): Promise<PaginatedResponse<SleepRecord>> {

    const query = new URLSearchParams();

    if (params?.from)  query.set('from', params.from);

    if (params?.to)    query.set('to', params.to);

    if (params?.page)  query.set('page', String(params.page));

    if (params?.limit) query.set('limit', String(params.limit));

    const qs = query.toString();

    return this.request(`/sleep_records${qs ? `?${qs}` : ''}`);

  }

}

export const apiClient = new ApiClient();