// ebay_command_line_tool.js
// A Node.js script to scrape eBay search results and output JSON.
// Uses ebay_core.js for parsing and extraction logic.
// Usage: node ebay_command_line_tool.js "EBAY_SEARCH_URL"

const puppeteer = require('puppeteer');
const fs = require('fs');
const path = require('path');

// --- Main Scraping Function ---
async function scrapeEbayFromCommandLine(url) {
    if (!url) {
        console.error("Error: eBay search URL is required as the first argument.");
        console.log("Example Usage: node ebay_command_line_tool.js \"https://www.ebay.com/sch/i.html?_nkw=ssd\"");
        process.exit(1);
    }

    // --- Load Core Script ---
    // This assumes ebay_core.js is in the same directory as this script.
    const coreScriptPath = path.join(__dirname, 'ebay_core.js');
    let ebayCoreScriptContent;
    try {
        ebayCoreScriptContent = fs.readFileSync(coreScriptPath, 'utf8');
        if (!ebayCoreScriptContent) {
            throw new Error("ebay_core.js is empty or could not be read properly.");
        }
    } catch (e) {
        console.error(`Error: Could not read ebay_core.js from ${coreScriptPath}`);
        console.error("Please ensure 'ebay_core.js' exists in the same directory as this script.");
        console.error(e.message);
        process.exit(1);
    }

    console.log(`Attempting to scrape: ${url}`);
    let browser; // Declare browser outside try so it can be closed in finally
    try {
        browser = await puppeteer.launch({
            headless: true, // Set to false for debugging to see the browser
            args: ['--no-sandbox', '--disable-setuid-sandbox'] // Common args for server environments
        });
        const page = await browser.newPage();
        await page.setUserAgent('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36');
        // Increase navigation timeout and wait until network is idle
        await page.goto(url, { waitUntil: 'networkidle2', timeout: 90000 });

        // --- Inject and Execute Core Logic ---
        // Inject the core parser script into the page context
        // This makes the EbayParser object available in the page's window scope
        await page.evaluate(ebayCoreScriptContent);

        // Now call the extraction function from the injected script
        const extractedResults = await page.evaluate(() => {
            // EbayParser should now be available on the window object
            if (typeof window.EbayParser === 'undefined' || typeof window.EbayParser.extractDataFromPage !== 'function') {
                // This error will be caught by the outer try/catch if thrown
                throw new Error("EbayParser or EbayParser.extractDataFromPage function was not properly injected or is missing in ebay_core.js!");
            }
            return window.EbayParser.extractDataFromPage(); // This calls the function defined in ebay_core.js
        });
        
        return extractedResults;

    } catch (e) {
        console.error("An error occurred during the scraping process:", e.message);
        // If running in a visible mode, a screenshot can be helpful.
        // if (browser && page) { // Check if page exists
        //     try {
        //        await page.screenshot({ path: 'ebay_scraping_error.png' });
        //        console.log("A screenshot 'ebay_scraping_error.png' has been saved for debugging.");
        //     } catch(se) { console.error("Could not save screenshot:", se.message); }
        // }
        return []; // Return empty array on error
    } finally {
        if (browser) {
            await browser.close();
        }
    }
}

// --- Script Execution ---
// The first actual argument to the script (process.argv[0] is node, process.argv[1] is the script path)
const searchUrl = process.argv[2];

(async () => {
    const data = await scrapeEbayFromCommandLine(searchUrl);
    if (data && data.length > 0) {
        console.log(JSON.stringify(data, null, 2));
    } else {
        console.log("No data extracted. This could be due to an error, an empty page, or incorrect selectors in ebay_core.js.");
    }
})();