#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
UPAS Replay module

Replay network traces and protocol sequences with support for multiple formats.
"""

import sys
import json
import time
import asyncio
import argparse
import logging

from pathlib import Path
from typing import Dict, Any


class TraceReplayer:
    """
    Network trace replay engine supporting multiple trace formats.
    """

    def __init__(self):
        """Initialize the trace replayer."""
        self.logger = logging.getLogger(__name__)
        self.trace_data = []
        self.replay_stats = {
            "packets_sent": 0,
            "replay_start_time": 0,
            "replay_duration": 0,
        }

    async def load_trace(self, trace_file: str, trace_format: str = "auto") -> bool:
        """
        Load trace file in various formats.

        :param trace_file: Path to trace file
        :type trace_file: str
        :param trace_format: Trace format (pcap, json, auto)
        :type trace_format: str
        :return: True if loaded successfully
        :rtype: bool
        """
        trace_path = Path(trace_file)

        if not trace_path.exists():
            self.logger.error(f"Trace file not found: {trace_file}")
            return False

        # Auto-detect format if needed
        if trace_format == "auto":
            trace_format = self._detect_format(trace_path)

        try:
            if trace_format == "json":
                await self._load_json_trace(trace_path)
            elif trace_format == "pcap":
                await self._load_pcap_trace(trace_path)
            elif trace_format == "upas":
                await self._load_upas_trace(trace_path)
            else:
                self.logger.error(f"Unsupported trace format: {trace_format}")
                return False

            self.logger.info(f"Loaded {len(self.trace_data)} packets from {trace_file}")
            return True

        except Exception as e:
            self.logger.error(f"Error loading trace: {e}")
            return False

    def _detect_format(self, trace_path: Path) -> str:
        """Auto-detect trace file format."""
        suffix = trace_path.suffix.lower()

        format_map = {
            ".json": "json",
            ".pcap": "pcap",
            ".cap": "pcap",
            ".upas": "upas",
        }

        return format_map.get(suffix, "unknown")

    async def _load_json_trace(self, trace_path: Path) -> None:
        """Load JSON format trace."""
        with open(trace_path, "r") as f:
            data = json.load(f)

        if isinstance(data, list):
            self.trace_data = data
        elif isinstance(data, dict) and "packets" in data:
            self.trace_data = data["packets"]
        else:
            raise ValueError("Invalid JSON trace format")

    async def _load_pcap_trace(self, trace_path: Path) -> None:
        """Load PCAP format trace (requires scapy)."""
        try:
            from scapy.all import rdpcap

            packets = rdpcap(str(trace_path))
            self.trace_data = []

            base_time = None
            for pkt in packets:
                if base_time is None:
                    base_time = float(pkt.time)

                packet_info = {
                    "timestamp": float(pkt.time) - base_time,
                    "size": len(pkt),
                    "raw_data": bytes(pkt).hex(),
                    "protocol": pkt.name if hasattr(pkt, "name") else "unknown",
                }

                # Extract layer information
                if hasattr(pkt, "summary"):
                    packet_info["summary"] = pkt.summary()

                self.trace_data.append(packet_info)

        except ImportError:
            raise ImportError("scapy required for PCAP format support")

    async def _load_upas_trace(self, trace_path: Path) -> None:
        """Load UPAS native trace format."""
        # UPAS native format would be defined here
        # For now, treat as JSON
        await self._load_json_trace(trace_path)

    async def replay_trace(self, speed: float = 1.0, loop: bool = False) -> None:
        """
        Replay the loaded trace.

        :param speed: Replay speed multiplier
        :type speed: float
        :param loop: Loop replay indefinitely
        :type loop: bool
        """
        if not self.trace_data:
            self.logger.error("No trace data loaded")
            return

        self.replay_stats["replay_start_time"] = time.time()

        try:
            while True:
                await self._replay_single_iteration(speed)

                if not loop:
                    break

                self.logger.info("Restarting trace replay...")

        except KeyboardInterrupt:
            self.logger.info("Replay interrupted by user")
        except Exception as e:
            self.logger.error(f"Replay error: {e}")
        finally:
            self.replay_stats["replay_duration"] = (
                time.time() - self.replay_stats["replay_start_time"]
            )
            self._print_replay_stats()

    async def _replay_single_iteration(self, speed: float) -> None:
        """Replay trace once."""

        for i, packet in enumerate(self.trace_data):
            # Calculate delay based on timestamp and speed
            if i > 0:
                delay = (
                    packet.get("timestamp", 0)
                    - self.trace_data[i - 1].get("timestamp", 0)
                ) / speed
                if delay > 0:
                    await asyncio.sleep(delay)

            # Send/process packet
            await self._process_packet(packet, i)

            self.replay_stats["packets_sent"] += 1

            # Progress reporting
            if (i + 1) % 100 == 0:
                progress = ((i + 1) / len(self.trace_data)) * 100
                self.logger.info(
                    f"Replay progress: {progress:.1f}% ({i+1}/{len(self.trace_data)})"
                )

    async def _process_packet(self, packet: Dict[str, Any], index: int) -> None:
        """
        Process a single packet during replay.

        :param packet: Packet data
        :type packet: dict
        :param index: Packet index in trace
        :type index: int
        """
        # Extract packet information
        timestamp = packet.get("timestamp", 0)
        size = packet.get("size", 0)
        protocol = packet.get("protocol", "unknown")

        # Log packet transmission
        self.logger.debug(
            f"[{index:04d}] t={timestamp:.3f}s proto={protocol} size={size}B"
        )

        # Here we would actually send the packet
        # For now, just simulate the transmission
        await asyncio.sleep(0.001)  # Simulate transmission time

    def _print_replay_stats(self) -> None:
        """Print replay statistics."""
        stats = self.replay_stats

        print("\n" + "=" * 50)
        print("REPLAY STATISTICS")
        print("=" * 50)
        print(f"Packets replayed: {stats['packets_sent']}")
        print(f"Total duration: {stats['replay_duration']:.2f} seconds")

        if stats["replay_duration"] > 0:
            pps = stats["packets_sent"] / stats["replay_duration"]
            print(f"Average rate: {pps:.1f} packets/second")

        print("=" * 50)


async def main():
    """
    Main replay entry point.

    :return: Exit code
    :rtype: int
    """
    parser = argparse.ArgumentParser(description="UPAS Protocol Replay Tool")
    parser.add_argument("trace_file", help="Trace file to replay")
    parser.add_argument(
        "-s",
        "--speed",
        type=float,
        default=1.0,
        help="Replay speed multiplier (default: 1.0)",
    )
    parser.add_argument(
        "-l", "--loop", action="store_true", help="Loop replay indefinitely"
    )
    parser.add_argument(
        "-f",
        "--format",
        choices=["auto", "json", "pcap", "upas"],
        default="auto",
        help="Trace file format (default: auto)",
    )
    parser.add_argument(
        "-v", "--verbose", action="store_true", help="Enable verbose logging"
    )

    args = parser.parse_args()

    # Setup logging
    log_level = logging.DEBUG if args.verbose else logging.INFO
    logging.basicConfig(
        level=log_level, format="%(asctime)s - %(name)s - %(levelname)s - %(message)s"
    )

    # Create and run replayer
    replayer = TraceReplayer()

    print("🎬 UPAS Trace Replay Tool")
    print(f"📁 Loading trace: {args.trace_file}")
    print(f"⚡ Speed: {args.speed}x")
    print(f"🔄 Loop: {'Yes' if args.loop else 'No'}")
    print(f"📊 Format: {args.format}")
    print("-" * 50)

    # Load trace
    if not await replayer.load_trace(args.trace_file, args.format):
        print("❌ Failed to load trace file")
        return 1

    # Start replay
    print("🚀 Starting replay...")
    await replayer.replay_trace(args.speed, args.loop)
    print("✅ Replay completed")

    return 0


def cli_main():
    """CLI entry point for replay functionality."""
    return asyncio.run(main())


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