import { getEnv } from "@/env";

const ORCHESTRATION_BASE_URL = getEnv("VITE_ORCHESTRATION_API_BASE_URL");
const SESSION_STORAGE_KEY = "chatbot_user";

export interface ApiEnvelope<T> {
  status?: "success" | "error" | string;
  message?: string;
  data: T;
}

export class ApiError extends Error {
  status: number;
  data: unknown;

  constructor(message: string, status: number, data?: unknown) {
    super(message);
    this.name = "ApiError";
    this.status = status;
    this.data = data;
  }
}

export interface AuthUser {
  id: string;
  email: string;
  fullname: string;
  role?: string;
  status?: string;
}

export interface AuthTokens {
  access_token: string;
  refresh_token: string;
  token_type?: string;
  expires_in?: number;
  refresh_expires_in?: number;
}

export interface UserSession extends AuthTokens {
  user_id: string;
  email: string;
  name: string;
  role?: string;
  status?: string;
  loginTime: string;
  expires_at?: string;
  refresh_expires_at?: string;
}

export interface LoginData extends AuthTokens {
  user: AuthUser;
}

export type LoginResponse = ApiEnvelope<LoginData>;
export type RefreshResponse = ApiEnvelope<LoginData>;

export type DocumentStatus = "uploading" | "uploaded" | "processing" | "processed" | "completed" | "failed";

export interface ApiDocument {
  id: string;
  user_id?: string;
  filename: string;
  blob_name?: string;
  status: DocumentStatus;
  file_size: number;
  file_type: string;
  created_at: string;
  processed_at?: string | null;
  error_message?: string | null;
}

export interface UploadDocumentResponse {
  status: string;
  message: string;
  data: ApiDocument;
}

export interface DocTypeInfo {
  type: string;
  max_size_mb: number;
  status: "active" | "inactive";
  message: string | null;
}

export type DbType = "postgres" | "mysql" | "sqlserver" | "supabase" | "bigquery" | "snowflake" | string;

export interface DbTypeField {
  name: string;
  type: "string" | "integer" | "select" | "boolean";
  required: boolean;
  default: string | number | boolean | null;
  description: string;
  options?: string[];
  sensitive?: boolean;
}

export interface DbTypeInfo {
  db_type: DbType;
  display_name: string;
  logo: string;
  status: "active" | "inactive";
  message: string | null;
  fields: DbTypeField[];
}

export interface DatabaseClient {
  id: string;
  user_id: string;
  name: string;
  db_type: DbType;
  status: "active" | "inactive" | string;
  created_at: string;
  updated_at: string | null;
}

export interface IngestColumn {
  name: string;
  data_type: string;
  nullable: boolean;
}

export interface IngestTable {
  name: string;
  row_count: number;
  columns: IngestColumn[];
  fks: Array<{ column_name: string; foreign_table: string; foreign_column_name: string }>;
}

export interface IngestResponse {
  tables: IngestTable[];
}

export interface DataCatalogSource {
  source_id: string;
  source_type: "schema" | "tabular" | "unstructured" | string;
  name: string;
  location_ref: string;
  table_count?: number;
  updated_at?: string;
}

export interface DataCatalog {
  user_id: string;
  schema_version: string;
  generated_at: string;
  sources: DataCatalogSource[];
}

export interface DataBindItem {
  id: string;
  name: string;
  group_type: "document" | "database";
  type: string;
}

export interface Analysis {
  id: string;
  user_id: string;
  analysis_title: string;
  objective: string;
  business_questions: string[];
  status: "active" | "inactive" | string;
  data_bind: DataBindItem[];
  data_bind_version: number;
  report_collection?: unknown[];
  created_at: string;
  updated_at: string;
}

export interface AnalysisListResponse {
  analyses: Analysis[];
  pagination?: {
    page: number;
    limit: number;
    total?: number;
    total_pages?: number;
  };
}

export interface AnalysisMessage {
  id: string;
  analysis_id: string;
  user_id: string;
  role: "user" | "ai";
  content: string;
  message_id?: string | null;
  status?: "success" | "failed";
  note?: string;
  created_at: string;
}

export const RESERVED_FAILED_MESSAGE_ID = "00000000-0000-0000-0000-000000000000";

export interface CreateAnalysisPayload {
  analysis_title: string;
  objective: string;
  business_questions: string[];
  data_bind: DataBindItem[];
}

export interface UpdateAnalysisPayload {
  analysis_title?: string;
  objective?: string;
  status?: "active" | "inactive";
}

function readStoredSession(): UserSession | null {
  try {
    const raw = localStorage.getItem(SESSION_STORAGE_KEY);
    return raw ? (JSON.parse(raw) as UserSession) : null;
  } catch {
    return null;
  }
}

function writeStoredSession(session: UserSession): void {
  localStorage.setItem(SESSION_STORAGE_KEY, JSON.stringify(session));
}

function clearStoredSession(): void {
  localStorage.removeItem(SESSION_STORAGE_KEY);
}

function secondsFromNow(seconds?: number): string | undefined {
  if (!seconds) return undefined;
  return new Date(Date.now() + seconds * 1000).toISOString();
}

function sessionFromAuthData(data: LoginData, previous?: UserSession | null): UserSession {
  return {
    user_id: data.user.id,
    email: data.user.email,
    name: data.user.fullname,
    role: data.user.role,
    status: data.user.status,
    access_token: data.access_token,
    refresh_token: data.refresh_token,
    token_type: data.token_type ?? "Bearer",
    expires_in: data.expires_in,
    refresh_expires_in: data.refresh_expires_in,
    expires_at: secondsFromNow(data.expires_in),
    refresh_expires_at: secondsFromNow(data.refresh_expires_in),
    loginTime: previous?.loginTime ?? new Date().toISOString(),
  };
}

async function parseError(res: Response): Promise<ApiError> {
  const body = await res.json().catch(() => null);
  const message =
    (body && typeof body === "object" && "message" in body && String((body as { message?: string }).message)) ||
    (body && typeof body === "object" && "detail" in body && String((body as { detail?: string }).detail)) ||
    `HTTP ${res.status}`;
  return new ApiError(message, res.status, body);
}

let _refreshPromise: Promise<UserSession | null> | null = null;

async function refreshWithStoredSession(): Promise<UserSession | null> {
  if (_refreshPromise) return _refreshPromise;

  _refreshPromise = (async () => {
    const current = readStoredSession();
    if (!current?.refresh_token) return null;

    const res = await fetch(`${ORCHESTRATION_BASE_URL}/api/refresh`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ refresh_token: current.refresh_token }),
    });

    if (!res.ok) {
      clearStoredSession();
      return null;
    }

    const envelope = (await res.json()) as RefreshResponse;
    const next = sessionFromAuthData(envelope.data, current);
    writeStoredSession(next);
    return next;
  })().finally(() => {
    _refreshPromise = null;
  });

  return _refreshPromise;
}

async function orchestrationRequest<T>(path: string, options: RequestInit = {}, retry = true): Promise<T> {
  const session = readStoredSession();
  const headers = new Headers(options.headers);
  const hasFormBody = options.body instanceof FormData;

  if (!hasFormBody && !headers.has("Content-Type")) {
    headers.set("Content-Type", "application/json");
  }

  if (session?.access_token && !headers.has("Authorization")) {
    headers.set("Authorization", `${session.token_type ?? "Bearer"} ${session.access_token}`);
  }

  const res = await fetch(`${ORCHESTRATION_BASE_URL}${path}`, {
    ...options,
    headers,
  });

  if (res.status === 401 && retry) {
    const refreshed = await refreshWithStoredSession();
    if (refreshed) {
      return orchestrationRequest<T>(path, options, false);
    }
  }

  if (!res.ok) throw await parseError(res);
  if (res.status === 204) return undefined as T;
  return (await res.json()) as T;
}

export async function login(email: string, password: string): Promise<LoginResponse> {
  return orchestrationRequest<LoginResponse>("/api/login", {
    method: "POST",
    body: JSON.stringify({ email, password }),
  }, false);
}

export async function refreshSession(refreshToken: string): Promise<RefreshResponse> {
  return orchestrationRequest<RefreshResponse>("/api/refresh", {
    method: "POST",
    body: JSON.stringify({ refresh_token: refreshToken }),
  }, false);
}

export function persistAuthData(data: LoginData): UserSession {
  const session = sessionFromAuthData(data, readStoredSession());
  writeStoredSession(session);
  return session;
}

export const getDocuments = (userId: string): Promise<ApiDocument[]> =>
  orchestrationRequest<ApiEnvelope<ApiDocument[] | null>>(`/api/v1/documents/${encodeURIComponent(userId)}`)
    .then((res) => res.data ?? []);

export async function uploadDocument(userId: string, file: File): Promise<UploadDocumentResponse> {
  const form = new FormData();
  form.append("user_id", userId);
  form.append("file", file);

  return orchestrationRequest<UploadDocumentResponse>("/api/v1/document/upload", {
    method: "POST",
    body: form,
  });
}

export const processDocument = (userId: string, documentId: string) =>
  orchestrationRequest<ApiEnvelope<{ document_id: string; file_type: string; status: string }>>("/api/v1/document/process", {
    method: "POST",
    body: JSON.stringify({ user_id: userId, document_id: documentId }),
  });

export const deleteDocument = (userId: string, documentId: string) =>
  orchestrationRequest<ApiEnvelope<unknown>>("/api/v1/document/delete", {
    method: "DELETE",
    body: JSON.stringify({ document_id: documentId, user_id: userId }),
  });

export const getDocumentTypes = (): Promise<DocTypeInfo[]> =>
  orchestrationRequest<ApiEnvelope<DocTypeInfo[]>>("/api/v1/documents/doctypes").then((res) => res.data ?? []);

export const getDatabaseClientTypes = (): Promise<DbTypeInfo[]> =>
  orchestrationRequest<ApiEnvelope<DbTypeInfo[] | null>>("/api/v1/database-clients/dbtypes").then((res) => res.data ?? []);

export const connectDatabase = (
  userId: string,
  dbType: DbType,
  name: string,
  credentials: Record<string, string | number | boolean>
): Promise<DatabaseClient> =>
  orchestrationRequest<ApiEnvelope<DatabaseClient>>("/api/v1/database-clients", {
    method: "POST",
    body: JSON.stringify({ user_id: userId, name, db_type: dbType, credentials }),
  }).then((res) => res.data);

export const getDatabaseClients = (userId: string): Promise<DatabaseClient[]> =>
  orchestrationRequest<ApiEnvelope<DatabaseClient[] | null>>(`/api/v1/database-clients/${encodeURIComponent(userId)}`)
    .then((res) => res.data ?? []);

export const deleteDatabaseClient = (clientId: string, userId: string) =>
  orchestrationRequest<ApiEnvelope<unknown>>(
    `/api/v1/database-clients/${encodeURIComponent(clientId)}?user_id=${encodeURIComponent(userId)}`,
    { method: "DELETE" }
  );

export const ingestDatabaseClient = (clientId: string, userId: string): Promise<IngestResponse> =>
  orchestrationRequest<ApiEnvelope<IngestResponse>>(
    `/api/v1/database-clients/${encodeURIComponent(clientId)}/ingest?user_id=${encodeURIComponent(userId)}`,
    { method: "POST" }
  ).then((res) => res.data);

export const getDataCatalog = (userId: string): Promise<DataCatalog> =>
  orchestrationRequest<ApiEnvelope<DataCatalog>>(`/api/v1/data-catalog/${encodeURIComponent(userId)}`).then((res) => res.data);

export const rebuildDataCatalog = (userId: string): Promise<DataCatalog> =>
  orchestrationRequest<ApiEnvelope<DataCatalog>>("/api/v1/data-catalog/rebuild", {
    method: "POST",
    body: JSON.stringify({ user_id: userId }),
  }).then((res) => res.data);

function normalizeAnalysisList(data: AnalysisListResponse | Analysis[] | null): AnalysisListResponse {
  if (!data) return { analyses: [] };
  if (Array.isArray(data)) return { analyses: data };
  return { analyses: data.analyses ?? [], pagination: data.pagination };
}

export const listAnalyses = (params: { status?: "active" | "inactive"; page?: number; limit?: number } = {}) => {
  const query = new URLSearchParams();
  if (params.status) query.set("status", params.status);
  if (params.page) query.set("page", String(params.page));
  if (params.limit) query.set("limit", String(params.limit));
  const suffix = query.toString() ? `?${query.toString()}` : "";
  return orchestrationRequest<ApiEnvelope<AnalysisListResponse | Analysis[] | null>>(`/api/v1/analyses${suffix}`).then((res) =>
    normalizeAnalysisList(res.data)
  );
};

export const getAnalysis = (analysisId: string): Promise<Analysis> =>
  orchestrationRequest<ApiEnvelope<Analysis>>(`/api/v1/analyses/${encodeURIComponent(analysisId)}`).then((res) => res.data);

export const createAnalysis = (payload: CreateAnalysisPayload): Promise<Analysis> =>
  orchestrationRequest<ApiEnvelope<Analysis>>("/api/v1/analyses", {
    method: "POST",
    body: JSON.stringify(payload),
  }).then((res) => res.data);

export const updateAnalysis = (analysisId: string, payload: UpdateAnalysisPayload): Promise<Analysis> =>
  orchestrationRequest<ApiEnvelope<Analysis>>(`/api/v1/analyses/${encodeURIComponent(analysisId)}`, {
    method: "PATCH",
    body: JSON.stringify(payload),
  }).then((res) => res.data);

export const deleteAnalysis = (analysisId: string): Promise<void> =>
  orchestrationRequest<void>(`/api/v1/analyses/${encodeURIComponent(analysisId)}`, { method: "DELETE" });

export const updateAnalysisDataBind = (
  analysisId: string,
  expectedVersion: number,
  dataBind: DataBindItem[]
): Promise<Analysis> =>
  orchestrationRequest<ApiEnvelope<Analysis>>(`/api/v1/analyses/${encodeURIComponent(analysisId)}/data-bind`, {
    method: "PUT",
    body: JSON.stringify({ expected_version: expectedVersion, data_bind: dataBind }),
  }).then((res) => res.data);

export const getAnalysisDataCatalog = (analysisId: string): Promise<DataCatalog> =>
  orchestrationRequest<ApiEnvelope<DataCatalog>>(`/api/v1/analyses/${encodeURIComponent(analysisId)}/data-catalog`).then((res) => res.data);

export const rebuildAnalysisDataCatalog = (analysisId: string): Promise<DataCatalog> =>
  orchestrationRequest<ApiEnvelope<DataCatalog>>(`/api/v1/analyses/${encodeURIComponent(analysisId)}/data-catalog/rebuild`, {
    method: "POST",
  }).then((res) => res.data);

export const getAnalysisMessages = (analysisId: string, limit = 100): Promise<AnalysisMessage[]> =>
  orchestrationRequest<ApiEnvelope<{ messages?: AnalysisMessage[] } | AnalysisMessage[]>>(
    `/api/v1/analyses/${encodeURIComponent(analysisId)}/messages?limit=${encodeURIComponent(String(limit))}`
  ).then((res) => (Array.isArray(res.data) ? res.data : res.data.messages ?? []));

export const createAnalysisMessage = (
  analysisId: string,
  payload: { role: "user" | "ai"; content: string; message_id?: string }
): Promise<AnalysisMessage> =>
  orchestrationRequest<ApiEnvelope<{ message?: AnalysisMessage } | AnalysisMessage>>(
    `/api/v1/analyses/${encodeURIComponent(analysisId)}/messages`,
    {
      method: "POST",
      body: JSON.stringify(payload),
    }
  ).then((res) => ("message" in (res.data as object) ? (res.data as { message: AnalysisMessage }).message : (res.data as AnalysisMessage)));