"""
facebook.py  –  Facebook group scraper using Selenium.
Exports: scrape_facebook(username, password, groups) -> list[dict]

Returns structured data per-post:
  group_name, group_url, post_url, author, caption, comments
"""
from __future__ import annotations

import json
import os
import time

from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

from ._driver import _create_driver

COOKIES_FILE = "fb_cookies.json"
FB_BASE = "https://www.facebook.com"
MOBILE_FB = "https://m.facebook.com"


# ── Cookie helpers ─────────────────────────────────────────────────────────────

def _save_cookies(driver, path: str) -> None:
    try:
        with open(path, "w") as f:
            json.dump(driver.get_cookies(), f)
    except Exception as e:
        print(f"[Facebook] Gagal simpan cookies: {e}")


def _load_cookies(driver, path: str) -> bool:
    if not os.path.exists(path) or os.path.getsize(path) == 0:
        return False
    try:
        with open(path, "r") as f:
            cookies = json.load(f)
        for cookie in cookies:
            try:
                driver.add_cookie(cookie)
            except Exception:
                pass
        return True
    except Exception as e:
        print(f"[Facebook] Gagal load cookies: {e}")
        return False


# ── Login ──────────────────────────────────────────────────────────────────────

def _fb_login(driver, username: str, password: str) -> bool:
    wait = WebDriverWait(driver, 20)
    driver.get(MOBILE_FB)
    time.sleep(3)

    if os.path.exists(COOKIES_FILE):
        try:
            _load_cookies(driver, COOKIES_FILE)
            driver.refresh()
            time.sleep(4)
            if "login" not in driver.current_url and "checkpoint" not in driver.current_url:
                print("[Facebook] Login via cookies berhasil.")
                return True
            driver.delete_all_cookies()
            driver.get(MOBILE_FB)
            time.sleep(2)
        except Exception as e:
            pass

    print("[Facebook] Login manual username/password...")
    try:
        email_input = wait.until(EC.presence_of_element_located((By.CSS_SELECTOR, 'input[name="email"]')))
        pass_input = driver.find_element(By.CSS_SELECTOR, 'input[name="pass"]')
        email_input.clear()
        email_input.send_keys(username)
        pass_input.clear()
        pass_input.send_keys(password)
        pass_input.send_keys("\n")
        time.sleep(1)
        
        try:
            login_btn = driver.find_element(By.CSS_SELECTOR, 'button[name="login"], [data-sigil="m_login_button"], input[type="submit"]')
            driver.execute_script("arguments[0].click();", login_btn)
        except Exception:
            pass
    except Exception:
        try:
            driver.get(f"{FB_BASE}/login.php")
            time.sleep(3)
            email_input = wait.until(EC.presence_of_element_located((By.ID, "email")))
            pass_input = driver.find_element(By.ID, "pass")
            email_input.clear()
            email_input.send_keys(username)
            pass_input.clear()
            pass_input.send_keys(password)
            driver.find_element(By.NAME, "login").click()
        except Exception as e2:
            return False

    time.sleep(6)
    if "login" in driver.current_url or "checkpoint" in driver.current_url:
        return False

    _save_cookies(driver, COOKIES_FILE)
    return True


def ensure_logged_in(driver, username, password):
    try:
        url = driver.current_url
        if url and "login" in url:
            _fb_login(driver, username, password)
            return

        try:
            popup = driver.find_element(By.XPATH, '//div[contains(text(),"See more on Facebook")]')
            if popup.is_displayed():
                _fb_login(driver, username, password)
                return
        except: pass

        try:
            login_modal = driver.find_element(By.XPATH, '//input[@type="email" or @type="text"]')
            if login_modal.is_displayed():
                _fb_login(driver, username, password)
                return
        except: pass
    except: pass


# ── Scraping ───────────────────────────────────────────────────────────────────

def _scrape_group(driver, username, password, group_url: str, max_scrolls: int = 5) -> list:
    """Scrape posts from a single FB group URL. Returns list of dict strings."""
    posts: list = []
    
    group_url = group_url.replace("m.facebook.com", "www.facebook.com").replace("web.facebook.com", "www.facebook.com")
    print(f"[Facebook] Scraping grup: {group_url}")
    
    try:
        driver.get(group_url)
        time.sleep(6)
        ensure_logged_in(driver, username, password)
    except Exception as e:
        print(f"[Facebook] Gagal buka grup: {e}")
        return posts

    last_height = driver.execute_script("return document.body.scrollHeight")

    for scroll_n in range(max_scrolls):
        driver.execute_script("window.scrollTo(0, document.body.scrollHeight);")
        time.sleep(4)
        ensure_logged_in(driver, username, password)

        post_elements = driver.find_elements(By.XPATH, '//div[@role="article"]')
        print(f"[Facebook] Scroll {scroll_n + 1} → {len(post_elements)} artikel ditemukan")

        for idx, post in enumerate(post_elements):
            try:
                driver.execute_script("arguments[0].scrollIntoView(true);", post)
                time.sleep(1)

                permalink = None
                post_context = post
                try:
                    link_el = post.find_element(By.XPATH, ".//a[contains(@href,'/posts/')]")
                    permalink = link_el.get_attribute("href").split("?")[0]
                except:
                    try:
                        link_el = post.find_element(By.XPATH, ".//a[contains(@href,'/permalink/')]")
                        permalink = link_el.get_attribute("href").split("?")[0]
                    except:
                        try:
                            post_id = post.get_attribute("data-ft")
                            if post_id and "top_level_post_id" in post_id:
                                d = json.loads(post_id)
                                pid = d.get("top_level_post_id")
                                if pid:
                                    permalink = f"{group_url.rstrip('/').split('?')[0]}/posts/{pid}/"
                        except:
                            pass

                if not permalink:
                    permalink = group_url

                try:
                    driver.execute_script(f"window.open('{permalink}', '_blank');")
                    time.sleep(1)
                    driver.switch_to.window(driver.window_handles[-1])
                    time.sleep(3)
                    ensure_logged_in(driver, username, password)
                    post_context = driver.find_element(By.XPATH, "//div[@role='article']")
                except:
                    post_context = None

                author = "Unknown"
                try:
                    if post_context:
                        try:
                            author = post_context.find_element(By.XPATH, ".//h2//span//span").text.strip()
                        except:
                            try:
                                author = post_context.find_element(By.XPATH, ".//strong//span").text.strip()
                            except:
                                author = post_context.find_element(By.XPATH, ".//span[contains(@class,'x193iq5w xeuugli x13faqbe x1vvkbs x1xmvt09 x1nxh6w3 x1sibtaa x1s688f xi81zsa')]").text.strip()
                except: pass

                # Expand comments if permalink tab is open
                if post_context:
                    while True:
                        try:
                            btn = post_context.find_element(By.XPATH, ".//span[contains(text(),'Lihat komentar') or contains(text(),'View more comments')]")
                            driver.execute_script("arguments[0].click();", btn)
                            time.sleep(2)
                        except: break
                    while True:
                        try:
                            btn = post_context.find_element(By.XPATH, ".//span[contains(text(),'Lihat') and contains(text(),'balasan')] | .//span[contains(text(),'View') and contains(text(),'replies')]")
                            driver.execute_script("arguments[0].click();", btn)
                            time.sleep(2)
                        except: break

                caption = ""
                comments = []
                if post_context:
                    try:
                        blocks = post_context.find_elements(By.XPATH, ".//div[@data-ad-rendering-role='story_message']//div[@dir='auto']")
                        caption = "\n".join([b.text.strip() for b in blocks if b.text.strip()])[:2000]
                    except: pass
                    try:
                        comment_blocks = post_context.find_elements(By.XPATH, ".//div[@aria-label='Komentar' or @aria-label='Comment']//div[@dir='auto']")
                        seen_c = set()
                        for cb in comment_blocks:
                            c = cb.text.strip()
                            if c and c not in seen_c:
                                seen_c.add(c)
                                comments.append(c)
                    except: pass

                if len(driver.window_handles) > 1:
                    driver.close()
                    driver.switch_to.window(driver.window_handles[0])

                if caption or comments:
                    posts.append({
                        "group_name": group_url.split("/")[-1] if not group_url.endswith("/") else group_url.split("/")[-2],
                        "group_url": group_url,
                        "post_url": permalink,
                        "author": author,
                        "caption": caption,
                        "comments": comments
                    })
            except Exception as e:
                print(f"[Facebook] Error baca post: {e}")
                if len(driver.window_handles) > 1:
                    driver.close()
                    driver.switch_to.window(driver.window_handles[0])
                continue

        new_height = driver.execute_script("return document.body.scrollHeight")
        if new_height == last_height:
            break
        last_height = new_height

    return posts


# ── Public API ─────────────────────────────────────────────────────────────────

def scrape_facebook(username: str, password: str, groups: list | None = None) -> list:
    if not username or not password:
        print("[Facebook] Username/password tidak disediakan.")
        return []

    if not groups:
        print("[Facebook] Tidak ada URL grup yang disediakan — skip.")
        return []

    driver = _create_driver(mobile=False)
    all_data: list = []

    try:
        if not _fb_login(driver, username, password):
            return []

        for group_url in groups:
            if not group_url or not group_url.strip():
                continue
            data = _scrape_group(driver, username, password, group_url.strip())
            all_data.extend(data)

    except Exception as e:
        print(f"[Facebook] Fatal error: {e}")
    finally:
        try:
            driver.quit()
        except Exception:
            pass

    print(f"[Facebook] Total article posts dari Facebook: {len(all_data)}")
    return all_data