import re
import csv
import time
import json
import random
import sys
import html as html_lib
from urllib.request import Request, urlopen
from urllib.parse import urlparse, parse_qs

# Configuration
BASE_URL = "https://tnc-platform.web.app"
SITEMAP_URL = f"{BASE_URL}/sitemap.xml"
USER_AGENT = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36"
# Firestore API Config
FIRESTORE_API_KEY = "AIzaSyA5AUOLUfpZ9VE0zWhi8-hF7t48_5wnT0s"
FIRESTORE_BASE_URL = "https://firestore.googleapis.com/v1/projects/tnc-platform/databases/(default)/documents/archive"

CSV_FILE = "tnc_seminars.csv"
JSONL_FILE = "tnc_seminars.jsonl"

def fetch_url(url):
    """Fetches URL content with a custom User-Agent."""
    try:
        req = Request(url, headers={"User-Agent": USER_AGENT})
        with urlopen(req, timeout=15) as response:
            return response.read().decode("utf-8", errors="replace")
    except Exception as e:
        print(f"Error fetching {url}: {e}", file=sys.stderr)
        return ""

def get_full_description(course_id):
    """Fetches the full description directly from Firestore REST API."""
    api_url = f"{FIRESTORE_BASE_URL}/{course_id}?key={FIRESTORE_API_KEY}"
    raw_json = fetch_url(api_url)
    if not raw_json:
        return ""
    
    try:
        data = json.loads(raw_json)
        # Firestore structure: fields -> description -> stringValue
        desc = data.get("fields", {}).get("description", {}).get("stringValue", "")
        
        # Cleanup: Remove "DESCRIPTION:" prefix if present
        if desc.upper().startswith("DESCRIPTION:"):
            desc = desc[len("DESCRIPTION:"):].strip()
        
        # Unescape HTML entities (like \u003cem\u003e or &)
        desc = html_lib.unescape(desc)
        # Optional: Remove HTML tags if they exist (like <em>)
        desc = re.sub(r'<[^>]+>', '', desc)
        
        return desc.strip()
    except Exception as e:
        print(f"Error parsing Firestore data for {course_id}: {e}", file=sys.stderr)
        return ""

def clean_title(title):
    """Removes the branding suffix from the title."""
    for sep in [" — ", " – ", " - "]:
        if sep in title:
            title = title.split(sep)[0]
    return html_lib.unescape(title.strip())

def main():
    print("Discovering seminars from sitemap...", file=sys.stderr)
    sitemap_xml = fetch_url(SITEMAP_URL)
    
    # Identify all course URLs
    # Pattern: https://tnc-platform.web.app/archive/course.html?id=13106
    course_urls = re.findall(r'<loc>(https://tnc-platform.web.app/archive/course.html\?id=(\d+))</loc>', sitemap_xml)
    
    # Deduplicate and sort
    seen_ids = set()
    unique_courses = []
    for url, cid in course_urls:
        if cid not in seen_ids:
            seen_ids.add(cid)
            unique_courses.append((url, cid))
    
    unique_courses.sort(key=lambda x: x[1], reverse=True) # Newest first
    print(f"Discovered {len(unique_courses)} seminars.", file=sys.stderr)

    if not unique_courses:
        print("No seminar URLs found in sitemap.", file=sys.stderr)
        return

    # Open both files for incremental writing
    with open(CSV_FILE, "w", encoding="utf-8", newline="") as f_csv, \
         open(JSONL_FILE, "w", encoding="utf-8") as f_jsonl:
        
        writer = csv.writer(f_csv)
        writer.writerow(["Seminar Title", "Seminar Description"])

        for i, (url, cid) in enumerate(unique_courses, 1):
            print(f"[{i}/{len(unique_courses)}] Scraping: {cid}", file=sys.stderr)
            
            # 1. Get Title from HTML (still easiest)
            html_text = fetch_url(url)
            title = "Unknown"
            if html_text:
                title_match = re.search(r"<title>(.*?)</title>", html_text, re.S | re.I)
                title = clean_title(title_match.group(1)) if title_match else "Unknown"

            # 2. Get FULL Description from Firestore API
            desc = get_full_description(cid)

            if title or desc:
                # Write to CSV
                writer.writerow([title, desc])
                f_csv.flush()
                
                # Write to JSONL
                json_row = json.dumps({"title": title, "description": desc}, ensure_ascii=False)
                f_jsonl.write(json_row + "\n")
                f_jsonl.flush()

            # Polite delay
            time.sleep(random.uniform(0.1, 0.3))

    print(f"\nSuccess! Full dataset saved to:", file=sys.stderr)
    print(f" - {CSV_FILE}", file=sys.stderr)
    print(f" - {JSONL_FILE}", file=sys.stderr)

if __name__ == "__main__":
    main()