#!/usr/bin/env python3
"""
One-off migration: copy packet_stream from a separate web viewer database
(e.g. bot_data.db) into the main bot database (e.g. meshcore_bot.db).

Use this when switching from split databases to the shared database so you
don't lose packet stream history. Run with bot and web viewer stopped.

Usage:
  python3 migrate_webviewer_db.py <source_db> <target_db>

Example:
  python3 migrate_webviewer_db.py bot_data.db meshcore_bot.db
"""

import sqlite3
import sys
from contextlib import closing


def main() -> int:
    if len(sys.argv) != 3:
        print("Usage: python3 migrate_webviewer_db.py <source_db> <target_db>", file=sys.stderr)
        print("Example: python3 migrate_webviewer_db.py bot_data.db meshcore_bot.db", file=sys.stderr)
        return 1

    source_path = sys.argv[1]
    target_path = sys.argv[2]

    if source_path == target_path:
        print("Source and target must be different files.", file=sys.stderr)
        return 1

    try:
        with closing(sqlite3.connect(target_path, timeout=30.0)) as conn:
            conn.execute("ATTACH DATABASE ? AS src", (source_path,))

            # Ensure packet_stream exists in target (same schema as web viewer)
            conn.execute("""
                CREATE TABLE IF NOT EXISTS packet_stream (
                    id INTEGER PRIMARY KEY AUTOINCREMENT,
                    timestamp REAL NOT NULL,
                    data TEXT NOT NULL,
                    type TEXT NOT NULL
                )
            """)
            conn.execute(
                "CREATE INDEX IF NOT EXISTS idx_packet_stream_timestamp ON packet_stream(timestamp)"
            )
            conn.execute(
                "CREATE INDEX IF NOT EXISTS idx_packet_stream_type ON packet_stream(type)"
            )

            # Check that source has packet_stream
            cur = conn.execute(
                "SELECT name FROM src.sqlite_master WHERE type='table' AND name='packet_stream'"
            )
            if cur.fetchone() is None:
                conn.execute("DETACH DATABASE src")
                print(f"Source database has no packet_stream table; nothing to migrate.", file=sys.stderr)
                return 0

            # Copy rows from source; skip ids that already exist in target (INSERT OR IGNORE)
            before = conn.total_changes
            conn.execute(
                """
                INSERT OR IGNORE INTO main.packet_stream (id, timestamp, data, type)
                SELECT id, timestamp, data, type FROM src.packet_stream
                """
            )
            inserted = conn.total_changes - before
            conn.commit()

            conn.execute("DETACH DATABASE src")

        print(f"Migrated {inserted} packet_stream row(s) from {source_path} to {target_path}.")
        return 0

    except sqlite3.OperationalError as e:
        print(f"Database error: {e}", file=sys.stderr)
        return 1
    except OSError as e:
        print(f"File error: {e}", file=sys.stderr)
        return 1


if __name__ == "__main__":
    sys.exit(main())