import { HTTPClient } from "../../http/HTTPClient";
import { ProviderError } from "../../models/errors";
import { SearchOptions } from "../../types/search";
import { ImageSearchResult } from "../models";
import { BaseImageProvider } from "./BaseImageProvider";

export const DDG_MAIN_URL = "https://duckduckgo.com/";
export const DDG_IMAGE_SEARCH_URL = "https://duckduckgo.com/i.js";
const VQD_REGEX = /vqd=(["']?)([\w-]+)\1/;

export interface DuckDuckGoImageProviderOptions {
  httpClient?: HTTPClient;
  httpTimeoutSeconds?: number;
}

/**
 * DuckDuckGo Image Search provider implementation.
 * Queries DuckDuckGo image search endpoints and normalizes response payloads.
 * Requires no API keys.
 * Mapped from Python `image_search/providers/duckduckgo.py` DuckDuckGoImageProvider.
 */
export class DuckDuckGoImageProvider extends BaseImageProvider {
  public static readonly PROVIDER_NAME = "duckduckgo";

  constructor(options: DuckDuckGoImageProviderOptions = {}) {
    super({
      providerName: DuckDuckGoImageProvider.PROVIDER_NAME,
      httpClient: options.httpClient,
      httpTimeoutSeconds: options.httpTimeoutSeconds,
    });
  }

  /**
   * Execute image search using DuckDuckGo endpoints.
   *
   * @param query Non-empty search query string.
   * @param options Search options (numResults, extra kwargs).
   * @returns List of normalized ImageSearchResult objects.
   * @throws ProviderError if VQD token extraction or HTTP request fails.
   */
  public async searchImages(
    query: string,
    options: SearchOptions = {}
  ): Promise<ImageSearchResult[]> {
    if (!query || !query.trim()) {
      return [];
    }

    const cleanQuery = query.trim();
    const numResults = options.numResults ?? 10;
    const { apiKey: _k, numResults: _n, provider: _p, ...extraKwargs } = options;

    const vqdToken = await this.fetchVqdToken(cleanQuery);
    if (!vqdToken) {
      throw new ProviderError("Failed to extract DuckDuckGo vqd verification token.");
    }

    const params: Record<string, string | number | boolean> = {
      l: "wt-wt",
      o: "json",
      q: cleanQuery,
      vqd: vqdToken,
      f: ",,,",
      p: "1",
      ...(extraKwargs as Record<string, string | number | boolean>),
    };

    const headers: Record<string, string> = {
      Referer: DDG_MAIN_URL,
      Accept: "application/json",
    };

    let response;
    try {
      response = await this._httpClient.get(DDG_IMAGE_SEARCH_URL, {
        params,
        headers,
      });
    } catch (exc: unknown) {
      const err = exc instanceof Error ? exc : new Error(String(exc));
      throw new ProviderError(`DuckDuckGo image search HTTP request failed: ${err.message}`);
    }

    if (response.statusCode !== 200 || !response.data || typeof response.data !== "object") {
      throw new ProviderError(
        `DuckDuckGo image search failed with status code ${response.statusCode}`
      );
    }

    const data = response.data as Record<string, unknown>;
    const rawResults = data.results;
    if (!Array.isArray(rawResults)) {
      return [];
    }

    const normalized = rawResults.map((item: unknown) =>
      this.normalizeResult((item as Record<string, unknown>) || {})
    );

    return normalized.slice(0, numResults);
  }

  /**
   * Fetch DuckDuckGo initial search page and extract VQD verification token via regex.
   * Mapped from Python `_fetch_vqd_token()`.
   */
  public async fetchVqdToken(query: string): Promise<string | null> {
    const params = { q: query };
    const headers = {
      "User-Agent":
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
    };

    try {
      const response = await this._httpClient.get(DDG_MAIN_URL, {
        params,
        headers,
      });
      if (response.statusCode === 200 && response.text) {
        const match = response.text.match(VQD_REGEX);
        if (match && match[2]) {
          return match[2];
        }
      }
    } catch {
      return null;
    }
    return null;
  }

  private normalizeResult(rawItem: Record<string, unknown>): ImageSearchResult {
    const imageUrl = String(rawItem.image || "");
    const sourceUrl = String(rawItem.url || "");

    let sourceDomain: string | undefined = undefined;
    if (sourceUrl) {
      try {
        const parsed = new URL(sourceUrl);
        sourceDomain = parsed.hostname;
      } catch {
        sourceDomain = undefined;
      }
    }

    return {
      title: String(rawItem.title || ""),
      imageUrl,
      sourceUrl,
      sourceDomain,
      width: typeof rawItem.width === "number" ? rawItem.width : undefined,
      height: typeof rawItem.height === "number" ? rawItem.height : undefined,
      thumbnailUrl: typeof rawItem.thumbnail === "string" ? rawItem.thumbnail : undefined,
      raw: rawItem,
    };
  }
}

import { HTTPClient } from "../../http/HTTPClient";
import { ProviderError } from "../../models/errors";
import { SearchOptions } from "../../types/search";
import { ImageSearchResult } from "../models";
import { BaseImageProvider } from "./BaseImageProvider";

export const DDG_MAIN_URL = "https://duckduckgo.com/";
export const DDG_IMAGE_SEARCH_URL = "https://duckduckgo.com/i.js";
const VQD_REGEX = /vqd=(["']?)([\w-]+)\1/;

export interface DuckDuckGoImageProviderOptions {
  httpClient?: HTTPClient;
  httpTimeoutSeconds?: number;
}

/**
 * DuckDuckGo Image Search provider implementation.
 * Queries DuckDuckGo image search endpoints and normalizes response payloads.
 * Requires no API keys.
 * Mapped from Python `image_search/providers/duckduckgo.py` DuckDuckGoImageProvider.
 */
export class DuckDuckGoImageProvider extends BaseImageProvider {
  public static readonly PROVIDER_NAME = "duckduckgo";

  constructor(options: DuckDuckGoImageProviderOptions = {}) {
    super({
      providerName: DuckDuckGoImageProvider.PROVIDER_NAME,
      httpClient: options.httpClient,
      httpTimeoutSeconds: options.httpTimeoutSeconds,
    });
  }

  /**
   * Execute image search using DuckDuckGo endpoints.
   *
   * @param query Non-empty search query string.
   * @param options Search options (numResults, extra kwargs).
   * @returns List of normalized ImageSearchResult objects.
   * @throws ProviderError if VQD token extraction or HTTP request fails.
   */
  public async searchImages(
    query: string,
    options: SearchOptions = {}
  ): Promise<ImageSearchResult[]> {
    if (!query || !query.trim()) {
      return [];
    }

    const cleanQuery = query.trim();
    const numResults = options.numResults ?? 10;
    const { apiKey: _k, numResults: _n, provider: _p, ...extraKwargs } = options;

    const vqdToken = await this.fetchVqdToken(cleanQuery);
    if (!vqdToken) {
      throw new ProviderError("Failed to extract DuckDuckGo vqd verification token.");
    }

    const params: Record<string, string | number | boolean> = {
      l: "wt-wt",
      o: "json",
      q: cleanQuery,
      vqd: vqdToken,
      f: ",,,",
      p: "1",
      ...(extraKwargs as Record<string, string | number | boolean>),
    };

    const headers: Record<string, string> = {
      Referer: DDG_MAIN_URL,
      Accept: "application/json",
    };

    let response;
    try {
      response = await this._httpClient.get(DDG_IMAGE_SEARCH_URL, {
        params,
        headers,
      });
    } catch (exc: unknown) {
      const err = exc instanceof Error ? exc : new Error(String(exc));
      throw new ProviderError(`DuckDuckGo image search HTTP request failed: ${err.message}`);
    }

    if (response.statusCode !== 200 || !response.data || typeof response.data !== "object") {
      throw new ProviderError(
        `DuckDuckGo image search failed with status code ${response.statusCode}`
      );
    }

    const data = response.data as Record<string, unknown>;
    const rawResults = data.results;
    if (!Array.isArray(rawResults)) {
      return [];
    }

    const normalized = rawResults.map((item: unknown) =>
      this.normalizeResult((item as Record<string, unknown>) || {})
    );

    return normalized.slice(0, numResults);
  }

  /**
   * Fetch DuckDuckGo initial search page and extract VQD verification token via regex.
   * Mapped from Python `_fetch_vqd_token()`.
   */
  public async fetchVqdToken(query: string): Promise<string | null> {
    const params = { q: query };
    const headers = {
      "User-Agent":
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
    };

    try {
      const response = await this._httpClient.get(DDG_MAIN_URL, {
        params,
        headers,
      });
      if (response.statusCode === 200 && response.text) {
        const match = response.text.match(VQD_REGEX);
        if (match && match[2]) {
          return match[2];
        }
      }
    } catch {
      return null;
    }
    return null;
  }

  private normalizeResult(rawItem: Record<string, unknown>): ImageSearchResult {
    const imageUrl = String(rawItem.image || "");
    const sourceUrl = String(rawItem.url || "");

    let sourceDomain: string | undefined = undefined;
    if (sourceUrl) {
      try {
        const parsed = new URL(sourceUrl);
        sourceDomain = parsed.hostname;
      } catch {
        sourceDomain = undefined;
      }
    }

    return {
      title: String(rawItem.title || ""),
      imageUrl,
      sourceUrl,
      sourceDomain,
      width: typeof rawItem.width === "number" ? rawItem.width : undefined,
      height: typeof rawItem.height === "number" ? rawItem.height : undefined,
      thumbnailUrl: typeof rawItem.thumbnail === "string" ? rawItem.thumbnail : undefined,
      raw: rawItem,
    };
  }
}