#!/usr/bin/env python3
"""Chrome Native Messaging host: append browser visits to local SQLite."""
import json, os, sqlite3, struct, sys
from datetime import datetime, timezone
from pathlib import Path

ARCHIVE_DIR = Path(os.environ.get("LOCAL_HISTORY_ARCHIVE_DIR", Path.home() / "ChromeHistoryArchive"))
DB_PATH = ARCHIVE_DIR / "history.sqlite3"

def read_message():
    raw = sys.stdin.buffer.read(4)
    if not raw: return None
    length = struct.unpack("=I", raw)[0]
    if length > 20_000_000: raise ValueError("Message too large")
    return json.loads(sys.stdin.buffer.read(length).decode("utf-8"))

def send_message(value):
    body = json.dumps(value, ensure_ascii=False).encode("utf-8")
    sys.stdout.buffer.write(struct.pack("=I", len(body)))
    sys.stdout.buffer.write(body)
    sys.stdout.buffer.flush()

def db():
    ARCHIVE_DIR.mkdir(parents=True, exist_ok=True)
    conn = sqlite3.connect(DB_PATH)
    conn.execute("PRAGMA journal_mode=WAL")
    conn.execute("""CREATE TABLE IF NOT EXISTS visits (
      id INTEGER PRIMARY KEY, url TEXT NOT NULL, title TEXT NOT NULL DEFAULT '',
      visit_time TEXT NOT NULL, transition TEXT, source TEXT NOT NULL,
      archived_at TEXT NOT NULL, UNIQUE(url, visit_time, source))""")
    conn.execute("CREATE INDEX IF NOT EXISTS idx_visits_time ON visits(visit_time)")
    return conn

def handle(message):
    if message.get("type") != "visits" or not isinstance(message.get("visits"), list):
        return {"ok": False, "error": "Expected a visits message"}
    now = datetime.now(timezone.utc).isoformat()
    rows = []
    for visit in message["visits"]:
        url, when = visit.get("url"), visit.get("visit_time")
        if isinstance(url, str) and url and isinstance(when, str) and when:
            rows.append((url, str(visit.get("title") or ""), when,
              str(visit.get("transition") or "observed"),
              str(visit.get("source") or "chrome-extension"), now))
    with db() as conn:
        conn.executemany("INSERT OR IGNORE INTO visits (url,title,visit_time,transition,source,archived_at) VALUES (?,?,?,?,?,?)", rows)
    return {"ok": True, "archived": len(rows), "database": str(DB_PATH)}

try:
    while message := read_message():
        try: send_message(handle(message))
        except Exception as exc: send_message({"ok": False, "error": str(exc)})
except Exception:
    sys.exit(1)