// ─── Types ────────────────────────────────────────────────────────────────────

export interface LoginResponse {
  status: string;
  message: string;
  data: {
    id: string;
    fullname: string;
    email: string;
    company: string;
    company_size: string;
    function: string;
    site: string;
    role: string;
    status: string;
    created_at: string;
  };
}

export interface Room {
  id: string;
  title: string;
  created_at: string;
  updated_at: string | null;
}

export interface CreateRoomResponse {
  status: string;
  message: string;
  data: Room;
}

export interface RoomMessage {
  id: string;
  role: "user" | "assistant";
  content: string;
  created_at: string;
}

export interface RoomDetail extends Room {
  messages: RoomMessage[];
}

export type DocumentStatus = "pending" | "processing" | "completed" | "failed";

export interface ApiDocument {
  id: string;
  filename: string;
  status: DocumentStatus;
  file_size: number;
  file_type: string;
  created_at: string;
}

export interface UploadDocumentResponse {
  status: string;
  message: string;
  data: { id: string; filename: string; status: DocumentStatus };
}

export interface ChatSource {
  document_id: string;
  filename: string;
  page_label: string | null;
}

// ─── Base Client ──────────────────────────────────────────────────────────────

const BASE_URL = ((import.meta as unknown as { env: Record<string, string> }).env.VITE_API_BASE_URL) ?? "";

async function request<T>(path: string, options?: RequestInit): Promise<T> {
  const res = await fetch(`${BASE_URL}${path}`, {
    headers: { "Content-Type": "application/json", ...options?.headers },
    ...options,
  });
  if (!res.ok) {
    const err = await res
      .json()
      .catch(() => ({ detail: `HTTP ${res.status}` }));
    throw new Error(err.detail ?? `HTTP ${res.status}`);
  }
  return res.json() as Promise<T>;
}

// ─── Auth ─────────────────────────────────────────────────────────────────────

export const login = (email: string, password: string) =>
  request<LoginResponse>("/api/login", {
    method: "POST",
    body: JSON.stringify({ email, password }),
  });

// ─── Rooms ────────────────────────────────────────────────────────────────────

export const getRooms = (userId: string) =>
  request<Room[]>(`/api/v1/rooms/${userId}`);

export const getRoom = (roomId: string) =>
  request<RoomDetail>(`/api/v1/room/${roomId}`);

export const deleteRoom = (roomId: string, userId: string) =>
  request<{ status: string; message: string }>(
    `/api/v1/room/${roomId}?user_id=${userId}`,
    { method: "DELETE" }
  );

export const createRoom = (userId: string, title?: string) =>
  request<CreateRoomResponse>("/api/v1/room/create", {
    method: "POST",
    body: JSON.stringify({ user_id: userId, title }),
  });

// ─── Documents ────────────────────────────────────────────────────────────────

export const getDocuments = (userId: string) =>
  request<ApiDocument[]>(`/api/v1/documents/${userId}`);

export const uploadDocument = async (
  userId: string,
  file: File
): Promise<UploadDocumentResponse> => {
  const form = new FormData();
  form.append("file", file);
  const res = await fetch(
    `${BASE_URL}/api/v1/document/upload?user_id=${userId}`,
    { method: "POST", body: form }
  );
  if (!res.ok) {
    const err = await res
      .json()
      .catch(() => ({ detail: `HTTP ${res.status}` }));
    throw new Error(err.detail ?? `HTTP ${res.status}`);
  }
  return res.json() as Promise<UploadDocumentResponse>;
};

export const processDocument = (userId: string, documentId: string) =>
  request<{
    status: string;
    message: string;
    data: { document_id: string; chunks_processed: number };
  }>(
    `/api/v1/document/process?document_id=${documentId}&user_id=${userId}`,
    { method: "POST" }
  );

export const deleteDocument = (userId: string, documentId: string) =>
  request<{ status: string; message: string }>(
    `/api/v1/document/delete?document_id=${documentId}&user_id=${userId}`,
    { method: "DELETE" }
  );

// ─── Chat ─────────────────────────────────────────────────────────────────────

export const streamChat = (
  userId: string,
  roomId: string,
  message: string
): Promise<Response> =>
  fetch(`${BASE_URL}/api/v1/chat/stream`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ user_id: userId, room_id: roomId, message }),
  });