#!/usr/bin/env python3
"""
Periodic Context Save Daemon

Monitors Claude Code activity and saves context every 5 minutes of active time.
Runs as a background process that tracks when Claude is actively working.

Usage:
    python .claude/hooks/periodic_context_save.py start
    python .claude/hooks/periodic_context_save.py stop
    python .claude/hooks/periodic_context_save.py status
"""

import os
import sys
import time
import json
import signal
import subprocess
from datetime import datetime, timezone
from pathlib import Path

import requests

# Configuration
SCRIPT_DIR = Path(__file__).parent
CLAUDE_DIR = SCRIPT_DIR.parent
PID_FILE = CLAUDE_DIR / ".periodic-save.pid"
STATE_FILE = CLAUDE_DIR / ".periodic-save-state.json"
LOG_FILE = CLAUDE_DIR / "periodic-save.log"
CONFIG_FILE = CLAUDE_DIR / "context-recall-config.env"

SAVE_INTERVAL_SECONDS = 300  # 5 minutes
CHECK_INTERVAL_SECONDS = 60  # Check every minute


def log(message):
    """Write log message to file and stderr"""
    timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
    log_message = f"[{timestamp}] {message}\n"

    # Write to log file
    with open(LOG_FILE, "a") as f:
        f.write(log_message)

    # Also print to stderr
    print(log_message.strip(), file=sys.stderr)


def load_config():
    """Load configuration from context-recall-config.env"""
    config = {
        "api_url": "http://172.16.3.30:8001",
        "jwt_token": None,
    }

    if CONFIG_FILE.exists():
        with open(CONFIG_FILE) as f:
            for line in f:
                line = line.strip()
                if line.startswith("CLAUDE_API_URL="):
                    config["api_url"] = line.split("=", 1)[1]
                elif line.startswith("JWT_TOKEN="):
                    config["jwt_token"] = line.split("=", 1)[1]

    return config


def detect_project_id():
    """Detect project ID from git config"""
    try:
        # Try git config first
        result = subprocess.run(
            ["git", "config", "--local", "claude.projectid"],
            capture_output=True,
            text=True,
            check=False,
        )
        if result.returncode == 0 and result.stdout.strip():
            return result.stdout.strip()

        # Try to derive from git remote URL
        result = subprocess.run(
            ["git", "config", "--get", "remote.origin.url"],
            capture_output=True,
            text=True,
            check=False,
        )
        if result.returncode == 0 and result.stdout.strip():
            import hashlib
            return hashlib.md5(result.stdout.strip().encode()).hexdigest()

    except Exception:
        pass

    return "unknown"


def is_claude_active():
    """
    Check if Claude Code is actively running.

    Returns True if:
    - Claude Code process is running
    - Recent file modifications in project directory
    - Not waiting for user input (heuristic)
    """
    try:
        # Check for Claude process on Windows
        if sys.platform == "win32":
            result = subprocess.run(
                ["tasklist.exe"],
                capture_output=True,
                text=True,
                check=False,
            )
            if "claude" in result.stdout.lower() or "node" in result.stdout.lower():
                return True

        # Check for recent file modifications (within last 2 minutes)
        cwd = Path.cwd()
        two_minutes_ago = time.time() - 120

        for file in cwd.rglob("*"):
            if file.is_file() and file.stat().st_mtime > two_minutes_ago:
                # Recent activity detected
                return True

    except Exception as e:
        log(f"Error checking activity: {e}")

    # Default to inactive if we can't detect
    return False


def load_state():
    """Load state from state file"""
    if STATE_FILE.exists():
        try:
            with open(STATE_FILE) as f:
                return json.load(f)
        except Exception:
            pass

    return {
        "active_seconds": 0,
        "last_update": None,
        "last_save": None,
    }


def save_state(state):
    """Save state to state file"""
    state["last_update"] = datetime.now(timezone.utc).isoformat()
    with open(STATE_FILE, "w") as f:
        json.dump(state, f, indent=2)


def save_periodic_context(config, project_id):
    """Save context to database via API"""
    if not config["jwt_token"]:
        log("No JWT token - cannot save context")
        return False

    title = f"Periodic Save - {datetime.now().strftime('%Y-%m-%d %H:%M')}"
    summary = f"Auto-saved context after 5 minutes of active work. Session in progress on project: {project_id}"

    payload = {
        "context_type": "session_summary",
        "title": title,
        "dense_summary": summary,
        "relevance_score": 5.0,
        "tags": json.dumps(["auto-save", "periodic", "active-session"]),
    }

    try:
        url = f"{config['api_url']}/api/conversation-contexts"
        headers = {
            "Authorization": f"Bearer {config['jwt_token']}",
            "Content-Type": "application/json",
        }

        response = requests.post(url, json=payload, headers=headers, timeout=10)

        if response.status_code in [200, 201]:
            log(f"✓ Context saved successfully (ID: {response.json().get('id', 'unknown')})")
            return True
        else:
            log(f"✗ Failed to save context: HTTP {response.status_code}")
            return False

    except Exception as e:
        log(f"✗ Error saving context: {e}")
        return False


def monitor_loop():
    """Main monitoring loop"""
    log("Periodic context save daemon started")
    log(f"Will save context every {SAVE_INTERVAL_SECONDS}s of active time")

    config = load_config()
    state = load_state()

    # Reset state on startup
    state["active_seconds"] = 0
    save_state(state)

    while True:
        try:
            # Check if Claude is active
            if is_claude_active():
                # Increment active time
                state["active_seconds"] += CHECK_INTERVAL_SECONDS
                save_state(state)

                log(f"Active: {state['active_seconds']}s / {SAVE_INTERVAL_SECONDS}s")

                # Check if we've reached the save interval
                if state["active_seconds"] >= SAVE_INTERVAL_SECONDS:
                    log(f"{SAVE_INTERVAL_SECONDS}s of active time reached - saving context")

                    project_id = detect_project_id()
                    if save_periodic_context(config, project_id):
                        state["last_save"] = datetime.now(timezone.utc).isoformat()

                    # Reset timer
                    state["active_seconds"] = 0
                    save_state(state)
            else:
                log("Claude Code inactive - not counting time")

            # Wait before next check
            time.sleep(CHECK_INTERVAL_SECONDS)

        except KeyboardInterrupt:
            log("Daemon stopped by user")
            break
        except Exception as e:
            log(f"Error in monitor loop: {e}")
            time.sleep(CHECK_INTERVAL_SECONDS)


def start_daemon():
    """Start the daemon as a background process"""
    if PID_FILE.exists():
        with open(PID_FILE) as f:
            pid = int(f.read().strip())

        # Check if process is running
        try:
            os.kill(pid, 0)  # Signal 0 checks if process exists
            print(f"Periodic context save daemon already running (PID: {pid})")
            return 1
        except OSError:
            # Process not running, remove stale PID file
            PID_FILE.unlink()

    # Start daemon process
    if sys.platform == "win32":
        # On Windows, use subprocess.Popen with DETACHED_PROCESS
        import subprocess
        CREATE_NO_WINDOW = 0x08000000

        process = subprocess.Popen(
            [sys.executable, __file__, "_monitor"],
            creationflags=subprocess.DETACHED_PROCESS | CREATE_NO_WINDOW,
            stdout=subprocess.DEVNULL,
            stderr=subprocess.DEVNULL,
        )
    else:
        # On Unix, fork
        import subprocess
        process = subprocess.Popen(
            [sys.executable, __file__, "_monitor"],
            stdout=subprocess.DEVNULL,
            stderr=subprocess.DEVNULL,
        )

    # Save PID
    with open(PID_FILE, "w") as f:
        f.write(str(process.pid))

    print(f"Started periodic context save daemon (PID: {process.pid})")
    print(f"Logs: {LOG_FILE}")
    return 0


def stop_daemon():
    """Stop the daemon"""
    if not PID_FILE.exists():
        print("Periodic context save daemon not running")
        return 1

    with open(PID_FILE) as f:
        pid = int(f.read().strip())

    try:
        if sys.platform == "win32":
            # On Windows, use taskkill
            subprocess.run(["taskkill", "/F", "/PID", str(pid)], check=True)
        else:
            # On Unix, use kill
            os.kill(pid, signal.SIGTERM)

        print(f"Stopped periodic context save daemon (PID: {pid})")
        PID_FILE.unlink()

        if STATE_FILE.exists():
            STATE_FILE.unlink()

        return 0

    except Exception as e:
        print(f"Failed to stop daemon (PID: {pid}): {e}")
        PID_FILE.unlink()
        return 1


def check_status():
    """Check daemon status"""
    if not PID_FILE.exists():
        print("Periodic context save daemon not running")
        return 1

    with open(PID_FILE) as f:
        pid = int(f.read().strip())

    # Check if process is running
    try:
        os.kill(pid, 0)
    except OSError:
        print("Daemon PID file exists but process not running")
        PID_FILE.unlink()
        return 1

    state = load_state()
    active_seconds = state.get("active_seconds", 0)

    print(f"Periodic context save daemon is running (PID: {pid})")
    print(f"Active time: {active_seconds}s / {SAVE_INTERVAL_SECONDS}s")

    if state.get("last_save"):
        print(f"Last save: {state['last_save']}")

    return 0


def main():
    """Main entry point"""
    if len(sys.argv) < 2:
        print("Usage: python periodic_context_save.py {start|stop|status}")
        print()
        print("Periodic context save daemon - saves context every 5 minutes of active time")
        print()
        print("Commands:")
        print("  start   - Start the background daemon")
        print("  stop    - Stop the daemon")
        print("  status  - Check daemon status")
        return 1

    command = sys.argv[1]

    if command == "start":
        return start_daemon()
    elif command == "stop":
        return stop_daemon()
    elif command == "status":
        return check_status()
    elif command == "_monitor":
        # Internal command - run monitor loop
        monitor_loop()
        return 0
    else:
        print(f"Unknown command: {command}")
        return 1


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