import * as SecureStore from "expo-secure-store";
import Constants from "expo-constants";

export class ApiError extends Error {
  status: number;
  fields?: Record<string, string>;

  constructor(message: string, status: number, fields?: Record<string, string>) {
    super(message);
    this.name = 'ApiError';
    this.status = status;
    this.fields = fields;
  }
}
import {
  User,
  AuthResponse,
  SignUpPayload,
  ResetPasswordRequestResponse,
  ResetPasswordResponse,
  UserUpdatePayload,
  CreateMoodEntryPayload,
  SleepRecordPayload,
  UpdateSleepRecordPayload,
  MoodEntry,
  SleepRecord,
  SleepRecordResponse,
  MoodEntryResponse,
  Trigger,
  TriggerResponse,
  CreateTriggerPayload,
  UpdateTriggerPayload,
  ActivateResponse,
  PaginatedResponse,
  InsightType,
  InsightPeriod,
  InsightMetadata,
  Insight,
  MedicineRegimen,
  MedicineRegimenResponse,
  CreateMedicineRegimenPayload,
  UpdateMedicineRegimenPayload,
  TodayMedicineEntry,
  UserPreferencesPayload,
  CareAction,
  CareActionType,
  CareActionResponse,
  CreateCareActionPayload,
  PatchCareActionPayload,
  TriggerMoodLink,
  LinkMoodPayload,
  AvatarResponse,
  RemoveAvatarResponse,
  ExportDataResponse,
} from "@/lib/api/types";

// Development builds already talk to Metro, so the API is on the same host.
// Release builds have no hostUri and always take the env var.
const API_BASE_URL =
  process.env.EXPO_PUBLIC_API_BASE_URL ??
  (Constants.expoConfig?.hostUri
    ? `http://${Constants.expoConfig.hostUri.split(":")[0]}:3000`
    : undefined);
const TOKEN_KEY = process.env.EXPO_PUBLIC_TOKEN_KEY;

class ApiClient {
  private onUnauthorizedCallback?: () => void;

  registerUnauthorizedHandler(cb: () => void) {
    this.onUnauthorizedCallback = cb;
  }

  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,
      },
    };

    let response: Response;

    console.log(`${API_BASE_URL}${endpoint} => with ${JSON.stringify(config)}`)

    try {
      response = await fetch(`${API_BASE_URL}${endpoint}`, config);
    } catch (err) {
      console.error("Underlying error: ", err)
      throw new ApiError("Sem conexão com o servidor", 0);
    }

    if (!response.ok) {
      if (response.status === 401) {
        this.onUnauthorizedCallback?.();
      }

      const body = await response
        .json()
        .catch(() => ({ error: "Network error" }));

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

      throw new ApiError(
        body.error || `HTTP ${response.status}`,
        response.status,
        body.fields,
      );
    }

    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 }),
    });

    if (response.token) {
      await this.storeToken(response.token);
    }

    return response;
  }

  async activate(code: string): Promise<ActivateResponse> {
    return this.request("/auth/activate", {
      method: "POST",
      body: JSON.stringify({ code }),
    });
  }

  async requestActivateCode(): Promise<void> {
    return this.request("/auth/resend_code", {
      method: "POST",
    });
  }

  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 logout(): Promise<void> {
    await this.removeToken();
  }

  // User-related
  async getMe(): Promise<{ user: User }> {
    return this.request('/users/me');
  }

  async completeOnboarding(): Promise<{ user: User }> {
    return this.request('/users/me/onboarding/complete', { method: 'POST' });
  }

  async updateUser(user: UserUpdatePayload): Promise<{ user: User }> {
    return await this.request(`/users/${user.id}`, {
      method: "PUT",
      body: JSON.stringify({ user }),
    });
  }

  async avatar(formData: FormData): Promise<AvatarResponse> {
    return await this.request<AvatarResponse>(`/users/me/avatar`, {
      method: "POST",
      body: formData,
    });
  }

  async removeAvatar(): Promise<RemoveAvatarResponse> {
    return await this.request<RemoveAvatarResponse>(`/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: SleepRecordPayload,
  ): 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}` : ""}`);
  }

  async getSleepRecord(id: string): Promise<SleepRecord> {
    return this.request(`/sleep_records/${id}`);
  }

  async updateSleepRecord(
    id: string,
    sleepRecord: UpdateSleepRecordPayload,
  ): Promise<SleepRecordResponse> {
    return await this.request(`/sleep_records/${id}`, {
      method: "PUT",
      body: JSON.stringify({ sleepRecord }),
    });
  }

  async deleteSleepRecord(id: string): Promise<void> {
    return this.request(`/sleep_records/${id}`, { method: "DELETE" });
  }

  // Trigger
  async createTrigger(trigger: CreateTriggerPayload): Promise<TriggerResponse> {
    return await this.request(`/triggers`, {
      method: "POST",
      body: JSON.stringify({ trigger }),
    });
  }

  async getTriggers(params?: {
    from?: string;
    to?: string;
    page?: number;
    limit?: number;
  }): Promise<PaginatedResponse<Trigger>> {
    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(`/triggers${qs ? `?${qs}` : ""}`);
  }

  async getTrigger(id: string): Promise<Trigger> {
    return this.request(`/triggers/${id}`);
  }

  async updateTrigger(
    id: string,
    trigger: UpdateTriggerPayload,
  ): Promise<TriggerResponse> {
    return await this.request(`/triggers/${id}`, {
      method: "PUT",
      body: JSON.stringify({ trigger }),
    });
  }

  async deleteTrigger(id: string): Promise<void> {
    return this.request(`/triggers/${id}`, { method: "DELETE" });
  }

  // Insights
  async getInsights<T extends InsightType = InsightType>(filters?: {
    type?: T;
    period?: InsightPeriod;
    limit?: number;
  }): Promise<{ insights: Insight<T>[] }> {
    const query = new URLSearchParams();
    if (filters?.type) query.set("type", filters.type);
    if (filters?.period) query.set("period", filters.period);
    if (filters?.limit) query.set("limit", String(filters.limit));

    const qs = query.toString();
    return this.request<{ insights: Insight<T>[] }>(
      `/insights${qs ? `?${qs}` : ""}`,
    );
  }

  // Medicine Regimens
  async getMedicineRegimens(): Promise<{ regimens: MedicineRegimen[] }> {
    return this.request('/medicine-regimens');
  }

  async getMedicineRegimen(id: string): Promise<{ regimen: MedicineRegimen }> {
    return this.request(`/medicine-regimens/${id}`);
  }

  async createMedicineRegimen(
    regimen: CreateMedicineRegimenPayload
  ): Promise<MedicineRegimenResponse> {
    return this.request('/medicine-regimens', {
      method: 'POST',
      body: JSON.stringify({ regimen })
    });
  }

  async updateMedicineRegimen(
    id: string,
    regimen: UpdateMedicineRegimenPayload
  ): Promise<MedicineRegimenResponse> {
    return this.request(`/medicine-regimens/${id}`, {
      method: 'PATCH',
      body: JSON.stringify({ regimen })
    });
  }

  async deleteMedicineRegimen(id: string): Promise<void> {
    return this.request(`/medicine-regimens/${id}`, { method: 'DELETE' });
  }

  async toggleMedicineRegimen(
    id: string,
    active: boolean,
  ): Promise<MedicineRegimenResponse> {
    return this.request(`/medicine-regimens/${id}/active`, {
      method: 'PATCH',
      body: JSON.stringify({ active }),
    });
  }

  async getMedicineRegimensToday(): Promise<{ regimens: TodayMedicineEntry[] }> {
    return this.request('/medicine-regimens/today');
  }

  async patchUserMe(payload: UserPreferencesPayload): Promise<{ user: User }> {
    return this.request('/users/me', {
      method: 'PATCH',
      body: JSON.stringify({ user: payload }),
    });
  }

  async exportData(): Promise<ExportDataResponse> {
    return this.request('/exports', { method: 'POST' });
  }

  // Care Actions
  async getCareActions(
    params?: {
      type?: CareActionType;
      from?: string;
      to?: string;
      page?: number;
      limit?: number
    }): Promise<PaginatedResponse<CareAction>> {
    const query = new URLSearchParams();
    if (params?.type) query.set('type', params.type);
    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(`/care-actions${qs ? `?${qs}` : ''}`);
  }

  async getCareAction(id: string): Promise<CareAction> {
    return this.request(`/care-actions/${id}`);
  }

  async createCareAction(payload: CreateCareActionPayload): Promise<CareActionResponse> {
    return this.request('/care-actions', {
      method: 'POST', body: JSON.stringify({ careAction: payload })
    });
  }

  async patchCareAction(
    id: string,
    payload: PatchCareActionPayload,
  ): Promise<CareAction> {
    return this.request(`/care-actions/${id}`, {
      method: 'PATCH',
      body: JSON.stringify({ careAction: payload }),
    });
  }

  async deleteCareAction(id: string): Promise<void> {
    return this.request(`/care-actions/${id}`, { method: 'DELETE' });
  }

  // Trigger to Mood linking
  async linkMoodToTrigger(
    triggerId: string, payload: LinkMoodPayload
  ): Promise<{ link: TriggerMoodLink }> {
    return this.request(`/triggers/${triggerId}/link-mood`, {
      method: 'POST',
      body: JSON.stringify(payload)
    });
  }

  async unlinkMoodFromTrigger(triggerId: string, moodId: string): Promise<void> {
    return this.request(`/triggers/${triggerId}/link-mood/${moodId}`, { method: 'DELETE' });
  }

  async generateReport(
    periodStart: string,
    periodEnd: string,
  ): Promise<ArrayBuffer> {
    const token = await this.getStoredToken()

    let response: Response
    try {
      response = await fetch(`${API_BASE_URL}/reports`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          ...(token && { Authorization: `Bearer ${token}` }),
        },
        body: JSON.stringify({ periodStart, periodEnd }),
      })
    } catch {
      throw new ApiError('Sem conexão com o servidor', 0)
    }

    if (!response.ok) {
      if (response.status === 401) this.onUnauthorizedCallback?.()
      const body = await response.json().catch(() => ({
        error: `HTTP ${response.status}`,
      }))
      throw new ApiError(body.error ?? `HTTP ${response.status}`, response.status)
    }

    return response.arrayBuffer()
  }
}

export const apiClient = new ApiClient();