import argparse
import gi
import glob
import os
import re
import struct

gi.require_version('Gst', '1.0')
from gi.repository import Gst, GLib

VIDEO_DIR = "/root/python"


def _natural_key(path):
    """Sort key so vid_2.mp4 comes before vid_10.mp4."""
    name = os.path.basename(path)
    return [int(t) if t.isdigit() else t.lower() for t in re.split(r'(\d+)', name)]


def build_video_list(video_dir=VIDEO_DIR):
    """Scan video_dir for .mp4 files and return them as sorted file:// URIs."""
    files = sorted(glob.glob(os.path.join(video_dir, "*.mp4")), key=_natural_key)
    if not files:
        raise SystemExit(f"No .mp4 files found in {video_dir!r}")
    return [Gst.filename_to_uri(os.path.abspath(f)) for f in files]


class KioskManager:
    def __init__(self, pipeline, videos):
        self.pipeline = pipeline
        self.videos = videos
        self.current_video_index = 0

        # Hardware Paths
        self.led_multi_path = "/sys/class/leds/display-indicator/multi_intensity"
        self.led_trig_path = "/sys/class/leds/display-indicator/trigger"
        self.led_br_path = "/sys/class/leds/display-indicator/brightness"

        # Hex to RGB Tuples
        self.colours = [
            (95, 1, 111),   # #5F016F
            (255, 51, 187), # #FF33BB
            (255, 128, 212),# #FF80D4
            (255, 173, 228) # #FFADE4
        ]
        self.colour_index = 0

        self.setup_led()

    def setup_led(self):
        try:
            if os.path.exists(self.led_trig_path):
                with open(self.led_trig_path, 'w') as f: f.write("none")
                with open(self.led_br_path, 'w') as f: f.write("255")
                self.change_led_colour()
        except Exception as e:
            print(f"LED Setup Error: {e}")

    def change_led_colour(self):
        """Cycles the next LED colour"""
        r, g, b = self.colours[self.colour_index]
        try:
            if os.path.exists(self.led_multi_path):
                with open(self.led_multi_path, 'w') as f:
                    f.write(f"{r} {g} {b}")
            print(f"Loop/Switch! LED: {r} {g} {b}")
            self.colour_index = (self.colour_index + 1) % len(self.colours)
        except Exception as e:
            print(f"Failed to write LED colour: {e}")

    def switch_video(self):
        """Advance to the next video in the list (loops around)"""
        self.pipeline.set_state(Gst.State.READY)
        self.current_video_index = (self.current_video_index + 1) % len(self.videos)
        new_uri = self.videos[self.current_video_index]

        print(f"Switching to {new_uri}")
        self.pipeline.set_property("uri", new_uri)
        self.pipeline.set_state(Gst.State.PLAYING)


def handle_button(source, condition, manager):
    """Listens to /dev/input/event1 - any key press skips to the next video."""
    EVENT_SIZE = 24
    data = source.read(EVENT_SIZE)
    if not data or len(data) < EVENT_SIZE:
        return True

    _, _, ev_type, ev_code, ev_value = struct.unpack('qqHHI', data)

    # EV_KEY (1), value 1 is press
    if ev_type == 1 and ev_value == 1:
        manager.change_led_colour()
        manager.switch_video()

    return True


def _resolve_start_index(start_name: str, videos: list) -> int:
    """Map a basename like 'vid.mp4' to its index in the videos list."""
    target = os.path.basename(start_name).lower()
    for i, uri in enumerate(videos):
        if os.path.basename(uri).lower() == target:
            return i
    raise SystemExit(
        f"--start {start_name!r} not in kiosk video list: "
        + ", ".join(os.path.basename(u) for u in videos)
    )


def play_kiosk(start_index: int = 0):
    Gst.init(None)

    pipeline = Gst.ElementFactory.make("playbin", "player")

    SINK_STR = ("videoconvert ! video/x-raw,format=BGRx ! "
                "kmssink driver-name=mxsfb-drm connector-id=37 plane-id=31 can-scale=false")
    video_sink = Gst.parse_bin_from_description(SINK_STR, True)
    pipeline.set_property("video-sink", video_sink)
    pipeline.set_property("audio-sink", Gst.ElementFactory.make("fakesink"))

    videos = build_video_list()
    if start_index >= len(videos):
        start_index = 0
    manager = KioskManager(pipeline, videos)
    manager.current_video_index = start_index
    pipeline.set_property("uri", manager.videos[start_index])
    print(f"Starting on: {manager.videos[start_index]}")

    # --- INPUT MONITORING ---
    try:
        btn_fd = open("/dev/input/event1", "rb")
        GLib.io_add_watch(btn_fd, GLib.IO_IN, handle_button, manager)
    except Exception as e:
        print(f"Button Node Error: {e}")

    # --- BUS MESSAGES ---
    bus = pipeline.get_bus()
    bus.add_signal_watch()

    def on_message(bus, msg, manager_instance):
        if msg.type == Gst.MessageType.EOS:
            # Video ended. Cycle LED and advance to the next video in the list.
            manager_instance.change_led_colour()
            manager_instance.switch_video()
        elif msg.type == Gst.MessageType.ERROR:
            err, debug = msg.parse_error()
            print(f"GStreamer Error: {err}")
            loop.quit()

    bus.connect("message", on_message, manager)

    pipeline.set_state(Gst.State.PLAYING)
    loop = GLib.MainLoop()

    try:
        loop.run()
    except KeyboardInterrupt:
        pipeline.set_state(Gst.State.NULL)

if __name__ == "__main__":
    p = argparse.ArgumentParser(description="Kiosk video player")
    p.add_argument("--start", default="vid_1.mp4",
                   help="Initial video filename (basename match against kiosk list)")
    # parse_known_args so legacy flags don't crash the kiosk
    args, _unknown = p.parse_known_args()

    # Gst must be initialised before build_video_list (it uses filename_to_uri).
    Gst.init(None)
    start_index = _resolve_start_index(args.start, build_video_list())
    play_kiosk(start_index=start_index)