import "server-only";

const ENDPOINT = process.env.NEXT_PUBLIC_APPWRITE_ENDPOINT!;
const PROJECT_ID = process.env.NEXT_PUBLIC_APPWRITE_PROJECT_ID!;

if (!ENDPOINT || !PROJECT_ID) {
  throw new Error(
    "Missing NEXT_PUBLIC_APPWRITE_ENDPOINT or NEXT_PUBLIC_APPWRITE_PROJECT_ID",
  );
}

export const DATABASE_ID = process.env.NEXT_PUBLIC_APPWRITE_DATABASE_ID!;
export const MEDIA_BUCKET_ID =
  process.env.NEXT_PUBLIC_APPWRITE_MEDIA_BUCKET_ID ?? "kovak-yazilim-media";

export const TABLES = {
  contactMessages: "contact_messages",
  services: "services",
  projects: "projects",
  blogPosts: "blog_posts",
  testimonials: "testimonials",
  seoPages: "seo_pages",
  seoSettings: "seo_settings",
} as const;

export class AppwriteError extends Error {
  code: number;
  type?: string;
  constructor(message: string, code: number, type?: string) {
    super(message);
    this.name = "AppwriteError";
    this.code = code;
    this.type = type;
  }
}

type FetchOpts = {
  method?: "GET" | "POST" | "PUT" | "PATCH" | "DELETE";
  body?: unknown;
  session?: string;
  query?: Record<string, string | string[] | number | undefined>;
  formData?: FormData;
};

async function aw<T>(path: string, opts: FetchOpts = {}): Promise<T> {
  const url = new URL(ENDPOINT + path);
  if (opts.query) {
    for (const [k, v] of Object.entries(opts.query)) {
      if (v === undefined) continue;
      if (Array.isArray(v)) v.forEach((x) => url.searchParams.append(k + "[]", String(x)));
      else url.searchParams.set(k, String(v));
    }
  }

  const headers: Record<string, string> = {
    "X-Appwrite-Project": PROJECT_ID,
    "X-Appwrite-Response-Format": "1.9.0",
  };
  if (opts.session) headers["X-Appwrite-Session"] = opts.session;

  let body: BodyInit | undefined;
  if (opts.formData) {
    body = opts.formData;
  } else if (opts.body !== undefined) {
    headers["Content-Type"] = "application/json";
    body = JSON.stringify(opts.body);
  }

  const res = await fetch(url, {
    method: opts.method ?? "GET",
    headers,
    body,
    cache: "no-store",
  });

  if (!res.ok) {
    let data: { message?: string; type?: string } = {};
    try {
      data = await res.json();
    } catch {
      /* ignore */
    }
    throw new AppwriteError(
      data.message || `HTTP ${res.status}`,
      res.status,
      data.type,
    );
  }

  const ct = res.headers.get("content-type") ?? "";
  if (ct.includes("application/json")) {
    return (await res.json()) as T;
  }
  return undefined as T;
}

// ─── Query helpers ───────────────────────────────────────────────

export const Q = {
  equal: (attr: string, value: string | number | boolean | string[]) =>
    JSON.stringify({
      method: "equal",
      attribute: attr,
      values: Array.isArray(value) ? value : [value],
    }),
  notEqual: (attr: string, value: string | number) =>
    JSON.stringify({ method: "notEqual", attribute: attr, values: [value] }),
  orderAsc: (attr: string) =>
    JSON.stringify({ method: "orderAsc", attribute: attr }),
  orderDesc: (attr: string) =>
    JSON.stringify({ method: "orderDesc", attribute: attr }),
  limit: (n: number) => JSON.stringify({ method: "limit", values: [n] }),
  offset: (n: number) => JSON.stringify({ method: "offset", values: [n] }),
};

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

export interface AwRow {
  $id: string;
  $createdAt: string;
  $updatedAt: string;
  [k: string]: unknown;
}
export interface AwListResponse<T> {
  total: number;
  rows: T[];
}
export interface AwFile {
  $id: string;
  name: string;
  sizeOriginal: number;
  mimeType: string;
  $createdAt: string;
}
export interface AwSession {
  $id: string;
  secret: string;
  expire: string;
  userId: string;
  provider: string;
}
export interface AwUser {
  $id: string;
  email: string;
  name: string;
  status: boolean;
}

// ─── Account ─────────────────────────────────────────────────────

export const account = {
  createEmailPasswordSession(email: string, password: string) {
    return aw<AwSession>("/account/sessions/email", {
      method: "POST",
      body: { email, password },
    });
  },
  get(session: string) {
    return aw<AwUser>("/account", { session });
  },
  deleteSession(sessionId: string, session: string) {
    return aw<void>(`/account/sessions/${sessionId}`, {
      method: "DELETE",
      session,
    });
  },
};

// ─── TablesDB ────────────────────────────────────────────────────

export const tablesDB = {
  listRows<T = AwRow>(
    databaseId: string,
    tableId: string,
    queries: string[] = [],
    session?: string,
  ) {
    return aw<AwListResponse<T>>(
      `/tablesdb/${databaseId}/tables/${tableId}/rows`,
      { query: { queries }, session },
    );
  },
  getRow<T = AwRow>(
    databaseId: string,
    tableId: string,
    rowId: string,
    session?: string,
  ) {
    return aw<T>(`/tablesdb/${databaseId}/tables/${tableId}/rows/${rowId}`, {
      session,
    });
  },
  createRow<T = AwRow>(
    databaseId: string,
    tableId: string,
    rowId: string,
    data: Record<string, unknown>,
    session?: string,
  ) {
    return aw<T>(`/tablesdb/${databaseId}/tables/${tableId}/rows`, {
      method: "POST",
      body: { rowId, data },
      session,
    });
  },
  updateRow<T = AwRow>(
    databaseId: string,
    tableId: string,
    rowId: string,
    data: Record<string, unknown>,
    session?: string,
  ) {
    return aw<T>(`/tablesdb/${databaseId}/tables/${tableId}/rows/${rowId}`, {
      method: "PATCH",
      body: { data },
      session,
    });
  },
  deleteRow(
    databaseId: string,
    tableId: string,
    rowId: string,
    session?: string,
  ) {
    return aw<void>(`/tablesdb/${databaseId}/tables/${tableId}/rows/${rowId}`, {
      method: "DELETE",
      session,
    });
  },
};

// ─── Storage ─────────────────────────────────────────────────────

export const storage = {
  listFiles(bucketId: string, queries: string[] = [], session?: string) {
    return aw<{ total: number; files: AwFile[] }>(
      `/storage/buckets/${bucketId}/files`,
      { query: { queries }, session },
    );
  },
  createFile(
    bucketId: string,
    fileId: string,
    file: File,
    session?: string,
  ) {
    const fd = new FormData();
    fd.append("fileId", fileId);
    fd.append("file", file);
    return aw<AwFile>(`/storage/buckets/${bucketId}/files`, {
      method: "POST",
      formData: fd,
      session,
    });
  },
  deleteFile(bucketId: string, fileId: string, session?: string) {
    return aw<void>(`/storage/buckets/${bucketId}/files/${fileId}`, {
      method: "DELETE",
      session,
    });
  },
  fileViewUrl(bucketId: string, fileId: string) {
    return `${ENDPOINT}/storage/buckets/${bucketId}/files/${fileId}/view?project=${PROJECT_ID}`;
  },
};

// ─── ID generator (Appwrite "unique()") ──────────────────────────

export const ID = {
  unique() {
    return "unique()";
  },
  custom(id: string) {
    return id;
  },
};