"""Macro Player — synchronized playback of audio + motion recordings.

Reads paired files:
  recordings/audio/<name>.wav
  recordings/motion/<name>.jsonl

Plays audio and streams joint commands simultaneously so the robot's
physical movements perfectly match the recorded speech timing.
"""

from __future__ import annotations

import json
import threading
import time
import wave
from pathlib import Path
from typing import Any

from Project.Sanad.config import AUDIO_RECORDINGS_DIR, MOTION_RECORDINGS_DIR, REPLAY_HZ
from Project.Sanad.core.config_loader import section as _cfg_section
from Project.Sanad.core.logger import get_logger

log = get_logger("macro_player")

_MP = _cfg_section("motion", "macro_player")
RAMP_IN_STEPS = _MP.get("ramp_in_steps", 60)
RAMP_OUT_STEPS = _MP.get("ramp_out_steps", 60)
WATCHDOG_DISABLE_AFTER = _MP.get("watchdog_disable_after_sec", 1.0)


def _lerp_q(a: list[float], b: list[float], t: float) -> list[float]:
    return [x + (y - x) * t for x, y in zip(a, b)]


class _ArmAdapter:
    """Uniform interface over either the public arm API or its private members.

    Hides the hasattr branching that previously polluted _play_motion. If the
    arm controller exposes the new public methods (get_current_q, send_frame,
    disable, state_age, wait_for_state) we use those; otherwise we fall back
    to the private versions for backward compatibility.
    """

    def __init__(self, arm):
        self._arm = arm

    def wait_for_state(self, timeout: float = 2.0) -> bool:
        fn = getattr(self._arm, "wait_for_state", None)
        if callable(fn):
            return fn(timeout=timeout)
        # No state-wait API: assume ready
        return True

    def get_current_q(self) -> list[float]:
        fn = getattr(self._arm, "get_current_q", None)
        if callable(fn):
            return fn()
        return self._arm._get_current_q()

    def send_frame(self, target_q: list[float], body_lock_q: list[float]):
        fn = getattr(self._arm, "send_frame", None)
        if callable(fn):
            return fn(target_q, body_lock_q)
        return self._arm._send_frame(target_q, body_lock_q)

    def disable(self):
        fn = getattr(self._arm, "disable", None)
        if callable(fn):
            return fn()
        return self._arm._disable_sdk()

    def state_age(self) -> float:
        fn = getattr(self._arm, "state_age", None)
        if callable(fn):
            return fn()
        # No watchdog support: pretend state is fresh
        return 0.0


class MacroPlayer:
    def __init__(self, audio_manager=None, arm_controller=None):
        self._audio_mgr = audio_manager
        self._arm = arm_controller
        self._lock = threading.Lock()
        self._playing = False
        self._stop_event = threading.Event()

    @property
    def is_playing(self) -> bool:
        return self._playing

    def play(self, name: str) -> dict[str, Any]:
        audio_path = AUDIO_RECORDINGS_DIR / f"{name}.wav"
        motion_path = MOTION_RECORDINGS_DIR / f"{name}.jsonl"

        if not audio_path.exists():
            raise FileNotFoundError(f"Audio not found: {audio_path}")
        if not motion_path.exists():
            raise FileNotFoundError(f"Motion not found: {motion_path}")

        with self._lock:
            if self._playing:
                raise RuntimeError("Macro playback already in progress.")
            self._playing = True
            self._stop_event.clear()

        t0 = time.monotonic()
        audio_thread = threading.Thread(target=self._play_audio, args=(audio_path,), daemon=True)
        motion_thread = threading.Thread(target=self._play_motion, args=(motion_path,), daemon=True)

        log.info("Macro playback starting: %s", name)
        audio_thread.start()
        motion_thread.start()

        audio_thread.join()
        motion_thread.join()

        elapsed = time.monotonic() - t0
        with self._lock:
            self._playing = False

        log.info("Macro playback complete: %s (%.1fs)", name, elapsed)
        return {"name": name, "duration_sec": round(elapsed, 2)}

    def stop(self):
        self._stop_event.set()
        # Best-effort: stop audio playback if the manager exposes a stop method
        if self._audio_mgr is not None and hasattr(self._audio_mgr, "stop_playback"):
            try:
                self._audio_mgr.stop_playback()
            except Exception as exc:
                log.warning("audio stop failed: %s", exc)

    def _play_audio(self, path: Path):
        if self._audio_mgr is None:
            log.warning("No audio manager — skipping audio playback")
            return
        try:
            self._audio_mgr.play_wav(path)
        except Exception as exc:
            log.error("Audio playback failed: %s", exc)

    def _play_motion(self, path: Path):
        """Stream JSONL motion frames at recorded timing — with ramp-in, watchdog, ramp-out."""
        frames = self._load_frames(path)
        if not frames:
            return

        if self._arm is None:
            # Simulated playback — just sleep through
            duration = frames[-1].get("t", 0)
            log.info("[SIM] MacroPlayer would play %d frames over %.1fs", len(frames), duration)
            time.sleep(min(duration, 30.0))
            return

        adapter = _ArmAdapter(self._arm)
        interval = 1.0 / REPLAY_HZ

        # CRITICAL: wait for first LowState before reading current pose
        if not adapter.wait_for_state(timeout=2.0):
            log.error("MacroPlayer aborting — no LowState received in 2s")
            return

        try:
            current_q = adapter.get_current_q()
        except Exception:
            log.exception("Failed to read current pose")
            return

        body_lock_q = list(current_q)
        first_frame_q = frames[0]["q"]

        # Phase 1: Ramp-in
        if not self._ramp(adapter, current_q, first_frame_q, body_lock_q, RAMP_IN_STEPS, "ramp-in"):
            return

        # Phase 2: Stream recorded frames with timing + watchdog
        last_q = self._stream_frames(adapter, frames, body_lock_q, interval) or first_frame_q

        # Phase 3: Ramp-out back to starting pose
        self._ramp(adapter, last_q, body_lock_q, body_lock_q, RAMP_OUT_STEPS, "ramp-out")

        # Phase 4: Disable arm SDK
        try:
            adapter.disable()
        except Exception:
            log.exception("disable() failed")

    def _load_frames(self, path: Path) -> list[dict]:
        """Read JSONL motion file. Returns list of frames or [] on failure."""
        frames: list[dict] = []
        try:
            with open(path, "r") as f:
                for line in f:
                    line = line.strip()
                    if not line:
                        continue
                    try:
                        data = json.loads(line)
                    except json.JSONDecodeError as exc:
                        log.warning("Skipping bad line in %s: %s", path.name, exc)
                        continue
                    if "q" in data:
                        frames.append(data)
        except OSError:
            log.exception("Failed to read motion file %s", path)
        if not frames:
            log.warning("No usable frames in %s", path.name)
        return frames

    def _ramp(self, adapter: "_ArmAdapter", from_q: list[float], to_q: list[float],
              body_lock_q: list[float], steps: int, label: str) -> bool:
        """Smoothly interpolate from `from_q` to `to_q` over `steps` frames.
        Returns True on success, False if cancelled or send failed."""
        log.info("MacroPlayer %s (%d steps)", label, steps)
        interval = 1.0 / REPLAY_HZ
        for step in range(steps):
            if self._stop_event.is_set():
                return False
            t = (step + 1) / steps
            interp = _lerp_q(from_q, to_q, t)
            try:
                adapter.send_frame(interp, body_lock_q)
            except Exception:
                log.exception("%s send_frame failed", label)
                return False
            time.sleep(interval)
        return True

    def _stream_frames(self, adapter: "_ArmAdapter", frames: list[dict],
                       body_lock_q: list[float], interval: float) -> list[float] | None:
        """Stream the recorded frames with watchdog. Returns the last successfully sent q."""
        t0 = time.monotonic()
        last_q: list[float] | None = None
        for frame in frames:
            if self._stop_event.is_set():
                break

            age = adapter.state_age()
            if age > WATCHDOG_DISABLE_AFTER:
                log.error("MacroPlayer watchdog abort — state stale %.2fs", age)
                break

            target_t = frame.get("t", 0)
            elapsed = time.monotonic() - t0
            sleep_time = target_t - elapsed
            if sleep_time > 0:
                time.sleep(sleep_time)

            try:
                adapter.send_frame(frame["q"], body_lock_q)
                last_q = frame["q"]
            except Exception:
                log.exception("send_frame failed mid-replay")
        return last_q

    def list_macros(self) -> list[dict[str, Any]]:
        """List available macro recordings (paired audio + motion)."""
        macros = []
        for audio_path in sorted(AUDIO_RECORDINGS_DIR.glob("*.wav")):
            name = audio_path.stem
            motion_path = MOTION_RECORDINGS_DIR / f"{name}.jsonl"
            if motion_path.exists():
                macros.append({
                    "name": name,
                    "audio_path": str(audio_path),
                    "motion_path": str(motion_path),
                    "audio_size_kb": round(audio_path.stat().st_size / 1024, 1),
                    "motion_size_kb": round(motion_path.stat().st_size / 1024, 1),
                })
        return macros

    def status(self) -> dict[str, Any]:
        return {"playing": self._playing}