import { Document } from "@langchain/core/documents";
import { CheerioWebBaseLoader } from "./cheerio.js";
/**
 * Class representing a document loader specifically designed for loading
 * documents from Gitbook. It extends the CheerioWebBaseLoader.
 */
export class GitbookLoader extends CheerioWebBaseLoader {
    constructor(webPath, params = {}) {
        const path = params.shouldLoadAllPaths === true ? `${webPath}/sitemap.xml` : webPath;
        super(path);
        Object.defineProperty(this, "webPath", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: webPath
        });
        Object.defineProperty(this, "shouldLoadAllPaths", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: false
        });
        Object.defineProperty(this, "baseUrl", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        this.baseUrl = webPath;
        this.webPath = path;
        this.shouldLoadAllPaths =
            params.shouldLoadAllPaths ?? this.shouldLoadAllPaths;
    }
    /**
     * Method that scrapes the web document using Cheerio and loads the
     * content based on the value of shouldLoadAllPaths. If shouldLoadAllPaths
     * is true, it calls the loadAllPaths() method to load all paths.
     * Otherwise, it calls the loadPath() method to load a single path.
     * @returns Promise resolving to an array of Document instances.
     */
    async load() {
        const $ = await this.scrape();
        if (this.shouldLoadAllPaths === true) {
            return this.loadAllPaths($);
        }
        return this.loadPath($);
    }
    /**
     * Private method that loads the content of a single path from the Gitbook
     * web document. It extracts the page content by selecting all elements
     * inside the "main" element, filters out empty text nodes, and joins the
     * remaining text nodes with line breaks. It extracts the title by
     * selecting the first "h1" element inside the "main" element. It creates
     * a Document instance with the extracted page content and metadata
     * containing the source URL and title.
     * @param $ CheerioAPI instance representing the loaded web document.
     * @param url Optional string representing the URL of the web document.
     * @returns Array of Document instances.
     */
    loadPath($, url) {
        const pageContent = $("main *")
            .contents()
            .toArray()
            .map((element) => element.type === "text" ? $(element).text().trim() : null)
            .filter((text) => text)
            .join("\n");
        const title = $("main h1").first().text().trim();
        return [
            new Document({
                pageContent,
                metadata: { source: url ?? this.webPath, title },
            }),
        ];
    }
    /**
     * Private method that loads the content of all paths from the Gitbook web
     * document. It extracts the URLs of all paths from the "loc" elements in
     * the sitemap.xml. It iterates over each URL, scrapes the web document
     * using the _scrape() method, and calls the loadPath() method to load the
     * content of each path. It collects all the loaded documents and returns
     * them as an array.
     * @param $ CheerioAPI instance representing the loaded web document.
     * @returns Promise resolving to an array of Document instances.
     */
    async loadAllPaths($) {
        const urls = $("loc")
            .toArray()
            .map((element) => $(element).text());
        const documents = [];
        for (const url of urls) {
            const buildUrl = url.includes(this.baseUrl) ? url : this.baseUrl + url;
            console.log(`Fetching text from ${buildUrl}`);
            const html = await GitbookLoader._scrape(buildUrl, this.caller, this.timeout);
            documents.push(...this.loadPath(html, buildUrl));
        }
        console.log(`Fetched ${documents.length} documents.`);
        return documents;
    }
}