/**
 * Palantir Foundry Datasets API.
 * Datasets, branches, transactions, files, schemas, table reads.
 *
 * File upload uses binary PUT with application/octet-stream content type
 * (NOT FormData). Schema endpoints use /getSchema and /putSchema verbs.
 *
 * @see https://www.palantir.com/docs/foundry/api/v2/datasets-v2-resources/
 */

import type { PalantirClient } from "./client.js";
import type {
  Dataset,
  CreateDatasetParams,
  Branch,
  CreateBranchParams,
  Transaction,
  CreateTransactionParams,
  FileMetadata,
  DatasetSchema,
  PageResponse,
  PageParams,
} from "./types.js";

export class DatasetsNamespace {
  constructor(private client: PalantirClient) {}

  // ─── Datasets ───────────────────────────────────────────────────

  /** Create a new dataset. */
  async create(params: CreateDatasetParams): Promise<Dataset> {
    return this.client.post("/api/v2/datasets", params);
  }

  /** Get a dataset by RID. */
  async get(datasetRid: string): Promise<Dataset> {
    return this.client.get(`/api/v2/datasets/${datasetRid}`);
  }

  // ─── Branches ───────────────────────────────────────────────────

  /** Get a specific branch. */
  async getBranch(datasetRid: string, branchId: string): Promise<Branch> {
    return this.client.get(`/api/v2/datasets/${datasetRid}/branches/${branchId}`);
  }

  /** List branches for a dataset. */
  async listBranches(
    datasetRid: string,
    params?: PageParams
  ): Promise<PageResponse<Branch>> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/branches`,
      params
    );
  }

  /** Create a branch. */
  async createBranch(
    datasetRid: string,
    params: CreateBranchParams
  ): Promise<Branch> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/branches`,
      params
    );
  }

  /** Delete a branch. */
  async deleteBranch(datasetRid: string, branchId: string): Promise<void> {
    return this.client.delete(
      `/api/v2/datasets/${datasetRid}/branches/${branchId}`
    );
  }

  // ─── Transactions ───────────────────────────────────────────────

  /** Create a transaction. */
  async createTransaction(
    datasetRid: string,
    params: CreateTransactionParams
  ): Promise<Transaction> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/transactions`,
      params
    );
  }

  /** Get a transaction. */
  async getTransaction(datasetRid: string, transactionRid: string): Promise<Transaction> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/transactions/${transactionRid}`
    );
  }

  /** List transactions for a dataset. Requires preview=true. */
  async listTransactions(
    datasetRid: string,
    params?: PageParams
  ): Promise<PageResponse<Transaction>> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/transactions`,
      { ...params, preview: true } as Record<string, unknown>
    );
  }

  /** Commit a transaction. */
  async commitTransaction(
    datasetRid: string,
    transactionRid: string
  ): Promise<Transaction> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/transactions/${transactionRid}/commit`
    );
  }

  /** Abort a transaction. */
  async abortTransaction(
    datasetRid: string,
    transactionRid: string
  ): Promise<Transaction> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/transactions/${transactionRid}/abort`
    );
  }

  // ─── File Operations ────────────────────────────────────────────
  // File upload uses binary PUT (application/octet-stream), NOT FormData.
  // @see https://www.palantir.com/docs/foundry/api/v2/datasets-v2-resources/files/upload-file

  /** List files in a dataset. */
  async listFiles(
    datasetRid: string,
    params?: PageParams & { branch?: string; endTransactionRid?: string; pathPrefix?: string }
  ): Promise<PageResponse<FileMetadata>> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/files`,
      params as Record<string, unknown>
    );
  }

  /** Get file metadata. */
  async getFile(
    datasetRid: string,
    filePath: string,
    params?: { branch?: string; endTransactionRid?: string }
  ): Promise<FileMetadata> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/files/${encodeURIComponent(filePath)}`,
      params as Record<string, unknown>
    );
  }

  /**
   * Delete a file from a dataset.
   * Uses query params (branchName or transactionRid), not path params.
   * @see https://www.palantir.com/docs/foundry/api/v2/datasets-v2-resources/files/delete-file
   */
  async deleteFile(
    datasetRid: string,
    filePath: string,
    params: { branchName?: string; transactionRid?: string }
  ): Promise<void> {
    const queryParams = new URLSearchParams();
    if (params.branchName) queryParams.set("branchName", params.branchName);
    if (params.transactionRid) queryParams.set("transactionRid", params.transactionRid);
    const qs = queryParams.toString();
    return this.client.delete(
      `/api/v2/datasets/${datasetRid}/files/${encodeURIComponent(filePath)}${qs ? `?${qs}` : ""}`
    );
  }

  /**
   * Upload a file to a dataset transaction.
   * Uses binary PUT with application/octet-stream content type.
   * The file path is URL-encoded in the endpoint path.
   */
  async uploadFile(
    datasetRid: string,
    transactionRid: string,
    filePath: string,
    content: string | Blob | ArrayBuffer | Uint8Array
  ): Promise<FileMetadata> {
    const token = await this.client.getAccessToken();

    const encodedPath = encodeURIComponent(filePath);
    const url = `${this.client.stackUrl}/api/v2/datasets/${datasetRid}/transactions/${transactionRid}/files/${encodedPath}/upload`;

    const body = typeof content === "string"
      ? new TextEncoder().encode(content)
      : content;

    const response = await this.client.rawFetch(url, {
      method: "PUT",
      headers: {
        Authorization: `Bearer ${token ?? ""}`,
        "Content-Type": "application/octet-stream",
      } as Record<string, string>,
      body: body as Blob | ArrayBuffer | Uint8Array,
    });

    if (!response.ok) {
      throw new Error(`File upload failed: ${response.status} ${response.statusText}`);
    }

    return response.json() as Promise<FileMetadata>;
  }

  /**
   * Read file content from a dataset as a raw Response stream.
   * Returns the fetch Response so the caller can consume the body as needed.
   */
  async readFileContent(
    datasetRid: string,
    filePath: string,
    params?: { branch?: string; endTransactionRid?: string }
  ): Promise<Response> {
    const token = await this.client.getAccessToken();

    const queryParams = new URLSearchParams();
    if (params?.branch) queryParams.set("branch", params.branch);
    if (params?.endTransactionRid) queryParams.set("endTransactionRid", params.endTransactionRid);

    const url = `${this.client.stackUrl}/api/v2/datasets/${datasetRid}/files/${encodeURIComponent(filePath)}/content?${queryParams.toString()}`;
    return this.client.rawFetch(url, {
      headers: { Authorization: `Bearer ${token ?? ""}` },
    });
  }

  // ─── Schema ─────────────────────────────────────────────────────
  // Schema endpoints use /getSchema (GET) and /putSchema (PUT) verbs.
  // @see https://www.palantir.com/docs/foundry/api/v2/datasets-v2-resources/datasets/get-schema

  /** Get the schema of a dataset. */
  async getSchema(
    datasetRid: string,
    params?: { branchName?: string; endTransactionRid?: string; versionId?: string }
  ): Promise<DatasetSchema> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/getSchema`,
      params as Record<string, unknown>
    );
  }

  /**
   * Get schemas for multiple datasets in a single request.
   * Max batch size: 1000.
   */
  async getSchemaBatch(
    items: Array<{ datasetRid: string; branchName?: string; endTransactionRid?: string; versionId?: string }>
  ): Promise<unknown> {
    return this.client.post(
      "/api/v2/datasets/getSchemaBatch",
      items
    );
  }

  /** Set the schema of a dataset. Supports optional query params for branch/transaction/reader. */
  async putSchema(
    datasetRid: string,
    schema: DatasetSchema,
    params?: { branchName?: string; endTransactionRid?: string; dataframeReader?: string }
  ): Promise<DatasetSchema> {
    const queryParams = new URLSearchParams();
    if (params?.branchName) queryParams.set("branchName", params.branchName);
    if (params?.endTransactionRid) queryParams.set("endTransactionRid", params.endTransactionRid);
    if (params?.dataframeReader) queryParams.set("dataframeReader", params.dataframeReader);
    const qs = queryParams.toString();
    return this.client.put(
      `/api/v2/datasets/${datasetRid}/putSchema${qs ? `?${qs}` : ""}`,
      schema
    );
  }

  /** Get schedules targeting this dataset. */
  async getSchedules(
    datasetRid: string,
    params?: PageParams & { branchName?: string }
  ): Promise<unknown> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/getSchedules`,
      params as Record<string, unknown>
    );
  }

  /** Get health checks configured for a dataset. */
  async getHealthChecks(
    datasetRid: string,
    params?: { branchName?: string; preview?: boolean }
  ): Promise<unknown> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/getHealthChecks`,
      { ...params, preview: true } as Record<string, unknown>
    );
  }

  /** Get health check reports for a dataset. */
  async getHealthCheckReports(
    datasetRid: string,
    params?: { branchName?: string; preview?: boolean }
  ): Promise<unknown> {
    return this.client.get(
      `/api/v2/datasets/${datasetRid}/getHealthCheckReports`,
      { ...params, preview: true } as Record<string, unknown>
    );
  }

  /** Get job RIDs for a dataset. */
  async getJobs(
    datasetRid: string,
    params?: PageParams & { branchName?: string; where?: Record<string, unknown>; orderBy?: Record<string, unknown>[] }
  ): Promise<unknown> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/jobs`,
      { ...params, preview: true }
    );
  }

  // ─── Table ──────────────────────────────────────────────────────

  /**
   * Read dataset as a table (structured rows).
   * Supports ARROW and CSV formats, column selection, and transaction scoping.
   * @see https://www.palantir.com/docs/foundry/api/v2/datasets-v2-resources/tables/read-table
   */
  async readTable(
    datasetRid: string,
    params?: PageParams & {
      branch?: string;
      rowLimit?: number;
      format?: "ARROW" | "CSV";
      columns?: string[];
      startTransactionRid?: string;
    }
  ): Promise<unknown> {
    return this.client.post(
      `/api/v2/datasets/${datasetRid}/readTable`,
      params
    );
  }
}