"""Debug replay camera management for replaying recordings with detection overlays."""

import logging
import os
import shutil
import subprocess as sp
import threading

from ruamel.yaml import YAML

from frigate.config import FrigateConfig
from frigate.config.camera.updater import (
    CameraConfigUpdateEnum,
    CameraConfigUpdatePublisher,
    CameraConfigUpdateTopic,
)
from frigate.const import (
    CLIPS_DIR,
    RECORD_DIR,
    REPLAY_CAMERA_PREFIX,
    REPLAY_DIR,
    THUMB_DIR,
)
from frigate.models import Recordings
from frigate.util.camera_cleanup import cleanup_camera_db, cleanup_camera_files
from frigate.util.config import find_config_file

logger = logging.getLogger(__name__)


class DebugReplayManager:
    """Manages a single debug replay session."""

    def __init__(self) -> None:
        self._lock = threading.Lock()
        self.replay_camera_name: str | None = None
        self.source_camera: str | None = None
        self.clip_path: str | None = None
        self.start_ts: float | None = None
        self.end_ts: float | None = None

    @property
    def active(self) -> bool:
        """Whether a replay session is currently active."""
        return self.replay_camera_name is not None

    def start(
        self,
        source_camera: str,
        start_ts: float,
        end_ts: float,
        frigate_config: FrigateConfig,
        config_publisher: CameraConfigUpdatePublisher,
    ) -> str:
        """Start a debug replay session.

        Args:
            source_camera: Name of the source camera to replay
            start_ts: Start timestamp
            end_ts: End timestamp
            frigate_config: Current Frigate configuration
            config_publisher: Publisher for camera config updates

        Returns:
            The replay camera name

        Raises:
            ValueError: If a session is already active or parameters are invalid
            RuntimeError: If clip generation fails
        """
        with self._lock:
            return self._start_locked(
                source_camera, start_ts, end_ts, frigate_config, config_publisher
            )

    def _start_locked(
        self,
        source_camera: str,
        start_ts: float,
        end_ts: float,
        frigate_config: FrigateConfig,
        config_publisher: CameraConfigUpdatePublisher,
    ) -> str:
        if self.active:
            raise ValueError("A replay session is already active")

        if source_camera not in frigate_config.cameras:
            raise ValueError(f"Camera '{source_camera}' not found")

        if end_ts <= start_ts:
            raise ValueError("End time must be after start time")

        # Query recordings for the source camera in the time range
        recordings = (
            Recordings.select(
                Recordings.path,
                Recordings.start_time,
                Recordings.end_time,
            )
            .where(
                Recordings.start_time.between(start_ts, end_ts)
                | Recordings.end_time.between(start_ts, end_ts)
                | ((start_ts > Recordings.start_time) & (end_ts < Recordings.end_time))
            )
            .where(Recordings.camera == source_camera)
            .order_by(Recordings.start_time.asc())
        )

        if not recordings.count():
            raise ValueError(
                f"No recordings found for camera '{source_camera}' in the specified time range"
            )

        # Create replay directory
        os.makedirs(REPLAY_DIR, exist_ok=True)

        # Generate replay camera name
        replay_name = f"{REPLAY_CAMERA_PREFIX}{source_camera}"

        # Build concat file for ffmpeg
        concat_file = os.path.join(REPLAY_DIR, f"{replay_name}_concat.txt")
        clip_path = os.path.join(REPLAY_DIR, f"{replay_name}.mp4")

        with open(concat_file, "w") as f:
            for recording in recordings:
                f.write(f"file '{recording.path}'\n")

        # Concatenate recordings into a single clip with -c copy (fast)
        ffmpeg_cmd = [
            frigate_config.ffmpeg.ffmpeg_path,
            "-hide_banner",
            "-y",
            "-f",
            "concat",
            "-safe",
            "0",
            "-i",
            concat_file,
            "-c",
            "copy",
            "-movflags",
            "+faststart",
            clip_path,
        ]

        logger.info(
            "Generating replay clip for %s (%.1f - %.1f)",
            source_camera,
            start_ts,
            end_ts,
        )

        try:
            result = sp.run(
                ffmpeg_cmd,
                capture_output=True,
                text=True,
                timeout=120,
            )
            if result.returncode != 0:
                logger.error("FFmpeg error: %s", result.stderr)
                raise RuntimeError(
                    f"Failed to generate replay clip: {result.stderr[-500:]}"
                )
        except sp.TimeoutExpired:
            raise RuntimeError("Clip generation timed out")
        finally:
            # Clean up concat file
            if os.path.exists(concat_file):
                os.remove(concat_file)

        if not os.path.exists(clip_path):
            raise RuntimeError("Clip file was not created")

        # Build camera config dict for the replay camera
        source_config = frigate_config.cameras[source_camera]
        camera_dict = self._build_camera_config_dict(
            source_config, replay_name, clip_path
        )

        # Build an in-memory config with the replay camera added
        config_file = find_config_file()
        yaml_parser = YAML()
        with open(config_file, "r") as f:
            config_data = yaml_parser.load(f)

        if "cameras" not in config_data or config_data["cameras"] is None:
            config_data["cameras"] = {}
        config_data["cameras"][replay_name] = camera_dict

        try:
            new_config = FrigateConfig.parse_object(config_data)
        except Exception as e:
            raise RuntimeError(f"Failed to validate replay camera config: {e}")

        # Update the running config
        frigate_config.cameras[replay_name] = new_config.cameras[replay_name]

        # Publish the add event
        config_publisher.publish_update(
            CameraConfigUpdateTopic(CameraConfigUpdateEnum.add, replay_name),
            new_config.cameras[replay_name],
        )

        # Store session state
        self.replay_camera_name = replay_name
        self.source_camera = source_camera
        self.clip_path = clip_path
        self.start_ts = start_ts
        self.end_ts = end_ts

        logger.info("Debug replay started: %s -> %s", source_camera, replay_name)
        return replay_name

    def stop(
        self,
        frigate_config: FrigateConfig,
        config_publisher: CameraConfigUpdatePublisher,
    ) -> None:
        """Stop the active replay session and clean up all artifacts.

        Args:
            frigate_config: Current Frigate configuration
            config_publisher: Publisher for camera config updates
        """
        with self._lock:
            self._stop_locked(frigate_config, config_publisher)

    def _stop_locked(
        self,
        frigate_config: FrigateConfig,
        config_publisher: CameraConfigUpdatePublisher,
    ) -> None:
        if not self.active:
            logger.warning("No active replay session to stop")
            return

        replay_name = self.replay_camera_name

        # Publish remove event so subscribers stop and remove from their config
        if replay_name in frigate_config.cameras:
            config_publisher.publish_update(
                CameraConfigUpdateTopic(CameraConfigUpdateEnum.remove, replay_name),
                frigate_config.cameras[replay_name],
            )
            # Do NOT pop here — let subscribers handle removal from the shared
            # config dict when they process the ZMQ message to avoid race conditions

        # Defensive DB cleanup
        self._cleanup_db(replay_name)

        # Remove filesystem artifacts
        self._cleanup_files(replay_name)

        # Reset state
        self.replay_camera_name = None
        self.source_camera = None
        self.clip_path = None
        self.start_ts = None
        self.end_ts = None

        logger.info("Debug replay stopped and cleaned up: %s", replay_name)

    def _build_camera_config_dict(
        self,
        source_config,
        replay_name: str,
        clip_path: str,
    ) -> dict:
        """Build a camera config dictionary for the replay camera.

        Args:
            source_config: Source camera's CameraConfig
            replay_name: Name for the replay camera
            clip_path: Path to the replay clip file

        Returns:
            Camera config as a dictionary
        """
        # Extract detect config (exclude computed fields)
        detect_dict = source_config.detect.model_dump(
            exclude={"min_initialized", "max_disappeared", "enabled_in_config"}
        )

        # Extract objects config, using .dict() on filters to convert
        # RuntimeFilterConfig ndarray masks back to string coordinates
        objects_dict = {
            "track": source_config.objects.track,
            "mask": {
                mask_id: (
                    mask_cfg.model_dump(
                        exclude={"raw_coordinates", "enabled_in_config"}
                    )
                    if mask_cfg is not None
                    else None
                )
                for mask_id, mask_cfg in source_config.objects.mask.items()
            }
            if source_config.objects.mask
            else {},
            "filters": {
                name: filt.dict() if hasattr(filt, "dict") else filt.model_dump()
                for name, filt in source_config.objects.filters.items()
            },
        }

        # Extract zones (exclude_defaults avoids serializing empty defaults
        # like distances=[] that fail validation on re-parse)
        zones_dict = {}
        for zone_name, zone_config in source_config.zones.items():
            zone_dump = zone_config.model_dump(
                exclude={"contour", "color"}, exclude_defaults=True
            )
            # Always include required fields
            zone_dump.setdefault("coordinates", zone_config.coordinates)
            zones_dict[zone_name] = zone_dump

        # Extract motion config (exclude runtime fields)
        motion_dict = {}
        if source_config.motion is not None:
            motion_dict = source_config.motion.model_dump(
                exclude={
                    "frame_shape",
                    "raw_mask",
                    "mask",
                    "improved_contrast_enabled",
                    "rasterized_mask",
                }
            )

        return {
            "enabled": True,
            "ffmpeg": {
                "inputs": [
                    {
                        "path": clip_path,
                        "roles": ["detect"],
                        "input_args": "-re -stream_loop -1 -fflags +genpts",
                    }
                ],
                "hwaccel_args": [],
            },
            "detect": detect_dict,
            "objects": objects_dict,
            "zones": zones_dict,
            "motion": motion_dict,
            "record": {"enabled": False},
            "snapshots": {"enabled": False},
            "review": {
                "alerts": {"enabled": False},
                "detections": {"enabled": False},
            },
            "birdseye": {"enabled": False},
            "audio": {"enabled": False},
            "lpr": {"enabled": False},
            "face_recognition": {"enabled": False},
        }

    def _cleanup_db(self, camera_name: str) -> None:
        """Defensively remove any database rows for the replay camera."""
        cleanup_camera_db(camera_name)

    def _cleanup_files(self, camera_name: str) -> None:
        """Remove filesystem artifacts for the replay camera."""
        cleanup_camera_files(camera_name)

        # Remove replay-specific cache directory
        if os.path.exists(REPLAY_DIR):
            try:
                shutil.rmtree(REPLAY_DIR)
                logger.debug("Removed replay cache directory")
            except Exception as e:
                logger.error("Failed to remove replay cache: %s", e)


def cleanup_replay_cameras() -> None:
    """Remove any stale replay camera artifacts on startup.

    Since replay cameras are memory-only and never written to YAML, they
    won't appear in the config after a restart. This function cleans up
    filesystem and database artifacts from any replay that was running when
    the process stopped.

    Must be called AFTER the database is bound.
    """
    stale_cameras: set[str] = set()

    # Scan filesystem for leftover replay artifacts to derive camera names
    for dir_path in [RECORD_DIR, CLIPS_DIR, THUMB_DIR]:
        if os.path.isdir(dir_path):
            for entry in os.listdir(dir_path):
                if entry.startswith(REPLAY_CAMERA_PREFIX):
                    stale_cameras.add(entry)

    if os.path.isdir(REPLAY_DIR):
        for entry in os.listdir(REPLAY_DIR):
            if entry.startswith(REPLAY_CAMERA_PREFIX) and entry.endswith(".mp4"):
                stale_cameras.add(entry.removesuffix(".mp4"))

    if not stale_cameras:
        return

    logger.info("Cleaning up stale replay camera artifacts: %s", list(stale_cameras))

    manager = DebugReplayManager()
    for camera_name in stale_cameras:
        manager._cleanup_db(camera_name)
        manager._cleanup_files(camera_name)

    if os.path.exists(REPLAY_DIR):
        try:
            shutil.rmtree(REPLAY_DIR)
        except Exception as e:
            logger.error("Failed to remove replay cache directory: %s", e)