require("dotenv").config();
const { Builder, By, until } = require("selenium-webdriver");
const chrome = require("selenium-webdriver/chrome");
const fs = require("fs");

function sleep(ms) {
  return new Promise((resolve) => setTimeout(resolve, ms));
}

async function initializeDriver() {
  const options = new chrome.Options();
  options.addArguments("--start-maximized");
  options.addArguments("--no-sandbox");
  options.addArguments("--disable-dev-shm-usage");
  options.addArguments("--disable-blink-features=AutomationControlled");
  options.addArguments(
    "--user-agent=Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"
  );
  return new Builder().forBrowser("chrome").setChromeOptions(options).build();
}

async function safeFindElement(element, by) {
  try {
    return await element.findElement(by);
  } catch (error) {
    return null;
  }
}

async function loginFacebook(driver, username, password, cookieFilePath) {
  await driver.get("https://www.facebook.com/login");
  try {
    const emailInput = await driver.wait(
      until.elementLocated(By.name("email")),
      10000
    );
    await emailInput.clear();
    await emailInput.sendKeys(username);
    const passInput = await driver.wait(
      until.elementLocated(By.name("pass")),
      10000
    );
    await passInput.clear();
    await passInput.sendKeys(password);
    const loginBtn = await driver.wait(
      until.elementLocated(By.name("login")),
      10000
    );
    await loginBtn.click();
    await sleep(5000);
    const currentUrl = await driver.getCurrentUrl();
    if (currentUrl.includes("login") || currentUrl.includes("checkpoint")) {
      throw new Error("Login failed!");
    }
    await saveCookies(driver, cookieFilePath);
    console.log("Auto login successful!");
    return true;
  } catch (e) {
    console.log("Auto login error:", e.message);
    return false;
  }
}

async function loadCookies(driver, cookieFilePath) {
  try {
    if (fs.existsSync(cookieFilePath)) {
      const cookies = JSON.parse(fs.readFileSync(cookieFilePath, "utf8"));
      await driver.get("https://www.facebook.com");
      await sleep(2000);
      for (const cookie of cookies) {
        try {
          await driver.manage().addCookie(cookie);
        } catch (error) {
          console.log(`Could not add cookie: ${cookie.name}`);
        }
      }
      console.log("Cookies loaded successfully!");
      await driver.navigate().refresh();
      await sleep(3000);
      return true;
    }
  } catch (error) {
    console.log("Error loading cookies:", error.message);
  }
  return false;
}

async function saveCookies(driver, cookieFilePath) {
  try {
    const cookies = await driver.manage().getCookies();
    fs.writeFileSync(cookieFilePath, JSON.stringify(cookies, null, 2));
    console.log("Cookies saved successfully!");
    return true;
  } catch (error) {
    console.log("Error saving cookies:", error.message);
    return false;
  }
}

async function getFirstPostBySelector(driver) {
  const postSelectors = [
    '[data-pagelet*="FeedUnit"]',
    '[role="article"]',
    '[data-testid="fbfeed_story"]',
    ".userContentWrapper",
    "[data-ft]",
    'div[data-pagelet="ProfileTimeline"]',
    '[data-pagelet="ProfileTimeline"] > div > div',
    'div[data-ad-preview="message"]',
  ];
  let firstPost = null;
  let usedSelector = "";
  for (const selector of postSelectors) {
    try {
      const posts = await driver.findElements(By.css(selector));
      if (posts.length > 0) {
        firstPost = posts[0];
        usedSelector = selector;
        break;
      }
    } catch (error) {
      continue;
    }
  }
  if (!firstPost) {
    console.log("No post found!");
    return null;
  }
  try {
    for (let i = 0; i < 3; i++) {
      await driver.executeScript(
        `
                var post = arguments[0];
                var btns = post.querySelectorAll('div[role="button"], button, span');
                for (var j=0; j<btns.length; j++) {
                    if (btns[j].innerText && (btns[j].innerText.trim() === 'See more' || btns[j].innerText.trim() === 'Xem thêm')) {
                        btns[j].click();
                    }
                }
            `,
        firstPost
      );
      await sleep(1200);
      const innerHTML = await firstPost.getAttribute("innerHTML");
      if (!innerHTML.includes("See more") && !innerHTML.includes("Xem thêm")) {
        break;
      }
    }
  } catch (e) {}
  return { firstPost, usedSelector };
}

(async function main() {
  let driver = await initializeDriver();
  const cookieFilePath = "facebook_cookies.json";
  const targetUrl =
    process.argv[2] || "https://www.facebook.com/logisticsarena.bacib.tdtu";
  const username = process.argv[4] || process.env.FB_USERNAME || "";
  const password = process.argv[5] || process.env.FB_PASSWORD || "";
  // const timeRetry = 5 * 60 * 1000;  // 5 minutes
  const timeRetry = 20 * 1000;

  if (!username || !password) {
    console.log(
      "Missing username or password! Pass via argv or set FB_USERNAME, FB_PASSWORD environment variables."
    );
    process.exit(1);
  }

  let postSet = new Set();
  let contentSet = new Set();
  if (fs.existsSync("facebook_first_post.json")) {
    try {
      const oldData = JSON.parse(
        fs.readFileSync("facebook_first_post.json", "utf8")
      );
      if (Array.isArray(oldData)) {
        oldData.forEach((item) => {
          if (item.postLink) postSet.add(item.postLink.split("?")[0]);
          if (item.content) contentSet.add(item.content.trim());
        });
      } else {
        if (oldData.postLink) postSet.add(oldData.postLink.split("?")[0]);
        if (oldData.content) contentSet.add(oldData.content.trim());
      }
    } catch (e) {}
  }

  try {
    let cookiesLoaded = await loadCookies(driver, cookieFilePath);
    let isLoggedIn = false;
    if (cookiesLoaded) {
      try {
        const currentUrl = await driver.getCurrentUrl();
        if (
          !currentUrl.includes("login") &&
          !currentUrl.includes("checkpoint")
        ) {
          isLoggedIn = true;
        }
      } catch (e) {}
    }
    if (!isLoggedIn) {
      let loginSuccess = await loginFacebook(
        driver,
        username,
        password,
        cookieFilePath
      );
      if (!loginSuccess) {
        process.exit(1);
      }
    }

    while (true) {
      await driver.get(targetUrl);
      await sleep(5000);
      const postResult = await getFirstPostBySelector(driver);
      if (!postResult) {
        console.log("No post found!");
      } else {
        const { firstPost, usedSelector } = postResult;
        let content = "";
        let contentElement = await safeFindElement(
          firstPost,
          By.css('div[data-ad-preview="message"]')
        );
        if (contentElement) content = await contentElement.getText();
        if (!content) {
          contentElement = await safeFindElement(
            firstPost,
            By.css(".userContent")
          );
          if (contentElement) content = await contentElement.getText();
        }
        if (!content) {
          contentElement = await safeFindElement(
            firstPost,
            By.css('div[role="article"]')
          );
          if (contentElement) content = await contentElement.getText();
        }
        if (!content) {
          contentElement = await safeFindElement(
            firstPost,
            By.css('div[data-testid="post_message"]')
          );
          if (contentElement) content = await contentElement.getText();
        }
        if (!content) {
          content = await firstPost.getText();
        }
        if (!content) content = "None content";

        let time = "";
        try {
          let timeElement = await safeFindElement(
            firstPost,
            By.css('a[aria-label][href*="/posts/"]')
          );
          time = timeElement ? await timeElement.getText() : "";
        } catch (e) {
          time = "";
        }
        let postLink = "";
        try {
          let linkElements = await firstPost.findElements(By.css("a"));
          for (const el of linkElements) {
            const href = await el.getAttribute("href");
            if (
              href &&
              (href.includes("/posts/") ||
                href.includes("/permalink/") ||
                href.includes("fbid="))
            ) {
              postLink = href;
              break;
            }
          }
        } catch (e) {}
        let postLinkKey = postLink ? postLink.split("?")[0] : "";
        let images = [];
        try {
          let imageElements = await firstPost.findElements(By.css("img"));
          for (const img of imageElements) {
            const src = await img.getAttribute("src");
            if (
              src &&
              src.startsWith("http") &&
              !src.includes("data:image") &&
              !src.includes("static.xx")
            ) {
              images.push(src);
            }
          }
        } catch (e) {}

        if (
          (postLinkKey && postSet.has(postLinkKey)) ||
          (content && contentSet.has(content.trim()))
        ) {
          console.log("Post already fetched or content duplicated, skipping!");
        } else {
          let newPost = {
            url: targetUrl,
            selector_used: usedSelector,
            content: content,
            postLink: postLink,
            images: images,
            timestamp: new Date().toISOString(),
            time: time,
          };
          let postsArr = [];
          if (fs.existsSync("facebook_first_post.json")) {
            try {
              const oldData = JSON.parse(
                fs.readFileSync("facebook_first_post.json", "utf8")
              );
              if (Array.isArray(oldData)) {
                postsArr = oldData;
              } else {
                postsArr = [oldData];
              }
            } catch (e) {}
          }
          postsArr.push(newPost);
          fs.writeFileSync(
            "facebook_first_post.json",
            JSON.stringify(postsArr, null, 2)
          );
          postSet.add(postLinkKey);
          contentSet.add(content.trim());
          console.log("Saved latest post to facebook_first_post.json");
        }
      }
      await sleep(timeRetry);
    }
  } catch (error) {
    console.error("Error:", error.message);
  } finally {
    setTimeout(async () => {
      await driver.quit();
      console.log("Browser closed");
    }, 10000);
  }
})();