import datetime
import itertools
import logging
import os
import random
import string
import subprocess as sp
import threading
from pathlib import Path

import psutil

from frigate.config import FrigateConfig
from frigate.const import RECORD_DIR
from frigate.models import Recordings

logger = logging.getLogger(__name__)

SECONDS_IN_DAY = 60 * 60 * 24


def remove_empty_directories(directory):
    # list all directories recursively and sort them by path,
    # longest first
    paths = sorted(
        [x[0] for x in os.walk(RECORD_DIR)],
        key=lambda p: len(str(p)),
        reverse=True,
    )
    for path in paths:
        # don't delete the parent
        if path == RECORD_DIR:
            continue
        if len(os.listdir(path)) == 0:
            os.rmdir(path)


class RecordingMaintainer(threading.Thread):
    def __init__(self, config: FrigateConfig, stop_event):
        threading.Thread.__init__(self)
        self.name = "recording_maint"
        self.config = config
        self.stop_event = stop_event

    def move_files(self):
        recordings = [
            d
            for d in os.listdir(RECORD_DIR)
            if os.path.isfile(os.path.join(RECORD_DIR, d)) and d.endswith(".mp4")
        ]

        files_in_use = []
        for process in psutil.process_iter():
            try:
                if process.name() != "ffmpeg":
                    continue
                flist = process.open_files()
                if flist:
                    for nt in flist:
                        if nt.path.startswith(RECORD_DIR):
                            files_in_use.append(nt.path.split("/")[-1])
            except:
                continue

        for f in recordings:
            if f in files_in_use:
                continue

            basename = os.path.splitext(f)[0]
            camera, date = basename.rsplit("-", maxsplit=1)
            start_time = datetime.datetime.strptime(date, "%Y%m%d%H%M%S")

            ffprobe_cmd = [
                "ffprobe",
                "-v",
                "error",
                "-show_entries",
                "format=duration",
                "-of",
                "default=noprint_wrappers=1:nokey=1",
                f"{os.path.join(RECORD_DIR, f)}",
            ]
            p = sp.run(ffprobe_cmd, capture_output=True)
            if p.returncode == 0:
                duration = float(p.stdout.decode().strip())
                end_time = start_time + datetime.timedelta(seconds=duration)
            else:
                logger.info(f"bad file: {f}")
                os.remove(os.path.join(RECORD_DIR, f))
                continue

            directory = os.path.join(
                RECORD_DIR, start_time.strftime("%Y-%m/%d/%H"), camera
            )

            if not os.path.exists(directory):
                os.makedirs(directory)

            file_name = f"{start_time.strftime('%M.%S.mp4')}"
            file_path = os.path.join(directory, file_name)

            os.rename(os.path.join(RECORD_DIR, f), file_path)

            rand_id = "".join(
                random.choices(string.ascii_lowercase + string.digits, k=6)
            )
            Recordings.create(
                id=f"{start_time.timestamp()}-{rand_id}",
                camera=camera,
                path=file_path,
                start_time=start_time.timestamp(),
                end_time=end_time.timestamp(),
                duration=duration,
            )

    def expire_files(self):
        delete_before = {}
        for name, camera in self.config.cameras.items():
            delete_before[name] = (
                datetime.datetime.now().timestamp()
                - SECONDS_IN_DAY * camera.record.retain_days
            )

        for p in Path("/media/frigate/recordings").rglob("*.mp4"):
            if not p.parent.name in delete_before:
                continue
            if p.stat().st_mtime < delete_before[p.parent.name]:
                Recordings.delete().where(Recordings.path == str(p)).execute()
                p.unlink(missing_ok=True)

    def run(self):
        for counter in itertools.cycle(range(60)):
            if self.stop_event.wait(10):
                logger.info(f"Exiting recording maintenance...")
                break

            # only expire events every 10 minutes, but check for new files every 10 seconds
            if counter == 0:
                self.expire_files()
                remove_empty_directories(RECORD_DIR)

            self.move_files()