"""Tests for cht.stream.ffmpeg — command compilation and pipeline construction."""

import os
import signal
import subprocess
from pathlib import Path
from unittest.mock import patch, MagicMock

import pytest

from cht.stream import ffmpeg as ff


class TestReceiveAndSegment:
    def test_compiles_to_valid_cmd(self, tmp_path):
        node = ff.receive_and_segment(
            "tcp://0.0.0.0:4444?listen", tmp_path, segment_duration=30
        )
        cmd = ff.compile_cmd(node)

        assert cmd[0] == "ffmpeg"
        assert "-hide_banner" in cmd
        assert "-loglevel" in cmd
        # Input options
        assert "tcp://0.0.0.0:4444?listen" in cmd
        # Segment output options
        assert "segment" in cmd
        assert "30" in cmd or 30 in cmd
        assert str(tmp_path / "segment_%04d.ts") in cmd

    def test_input_has_low_latency_flags(self, tmp_path):
        node = ff.receive_and_segment(
            "tcp://0.0.0.0:4444?listen", tmp_path
        )
        cmd = ff.compile_cmd(node)
        cmd_str = " ".join(str(c) for c in cmd)
        assert "nobuffer" in cmd_str
        assert "low_delay" in cmd_str

    def test_copy_codec(self, tmp_path):
        node = ff.receive_and_segment(
            "tcp://0.0.0.0:4444?listen", tmp_path
        )
        cmd = ff.compile_cmd(node)
        assert "copy" in cmd


class TestReceiveAndSegmentWithMonitor:
    def test_creates_fifo(self, tmp_path):
        fifo = tmp_path / "monitor.pipe"
        ff.receive_and_segment_with_monitor(
            "tcp://0.0.0.0:4444?listen", tmp_path, fifo
        )
        assert fifo.exists()
        assert os.path.isfile(fifo) or os.stat(fifo).st_mode & 0o010000  # is fifo

    def test_does_not_recreate_existing_fifo(self, tmp_path):
        fifo = tmp_path / "monitor.pipe"
        os.mkfifo(str(fifo))
        inode_before = fifo.stat().st_ino

        ff.receive_and_segment_with_monitor(
            "tcp://0.0.0.0:4444?listen", tmp_path, fifo
        )
        assert fifo.stat().st_ino == inode_before

    def test_has_two_outputs(self, tmp_path):
        fifo = tmp_path / "monitor.pipe"
        node = ff.receive_and_segment_with_monitor(
            "tcp://0.0.0.0:4444?listen", tmp_path, fifo
        )
        cmd = ff.compile_cmd(node)
        cmd_str = " ".join(str(c) for c in cmd)
        # Should have segment output and fifo output
        assert "segment_%04d.ts" in cmd_str
        assert "monitor.pipe" in cmd_str

    def test_both_outputs_use_copy(self, tmp_path):
        fifo = tmp_path / "monitor.pipe"
        node = ff.receive_and_segment_with_monitor(
            "tcp://0.0.0.0:4444?listen", tmp_path, fifo
        )
        cmd = ff.compile_cmd(node)
        # Should have copy codec for both outputs
        assert cmd.count("copy") >= 2


class TestExtractSceneFrames:
    def test_compiles_select_filter(self, tmp_path):
        # We can't run ffmpeg without a real file, but we can test compilation
        import ffmpeg
        stream = ffmpeg.input(str(tmp_path / "test.ts"))
        stream = stream.filter("select", "gt(scene\\,0.3)+gte(t-prev_selected_t\\,30)")
        stream = stream.filter("showinfo")
        output = ffmpeg.output(
            stream,
            str(tmp_path / "F%04d.jpg"),
            vsync="vfr",
            **{"q:v": "2"},
            start_number=1,
        )
        cmd = ff.compile_cmd(output)
        cmd_str = " ".join(str(c) for c in cmd)
        assert "select" in cmd_str
        assert "scene" in cmd_str
        assert "showinfo" in cmd_str
        assert "vfr" in cmd_str

    @patch("cht.stream.ffmpeg.subprocess.run")
    def test_calls_subprocess_with_timeout(self, mock_run, tmp_path):
        mock_run.return_value = MagicMock(stdout="", stderr="")
        ff.extract_scene_frames(
            tmp_path / "test.ts", tmp_path,
            scene_threshold=0.4, max_interval=20, start_number=5,
        )
        mock_run.assert_called_once()
        call_kwargs = mock_run.call_args
        assert call_kwargs.kwargs["timeout"] == 120
        assert call_kwargs.kwargs["capture_output"] is True

    @patch("cht.stream.ffmpeg.subprocess.run")
    def test_returns_stdout_stderr(self, mock_run, tmp_path):
        mock_run.return_value = MagicMock(stdout="out", stderr="err")
        stdout, stderr = ff.extract_scene_frames(
            tmp_path / "test.ts", tmp_path,
        )
        assert stdout == "out"
        assert stderr == "err"

    @patch("cht.stream.ffmpeg.subprocess.run")
    def test_start_number_in_cmd(self, mock_run, tmp_path):
        mock_run.return_value = MagicMock(stdout="", stderr="")
        ff.extract_scene_frames(
            tmp_path / "test.ts", tmp_path, start_number=42
        )
        cmd = mock_run.call_args.args[0]
        assert "42" in [str(c) for c in cmd]


class TestExtractAudioPcm:
    def test_compiles_audio_extraction(self, tmp_path):
        node = ff.extract_audio_pcm(tmp_path / "test.ts")
        cmd = ff.compile_cmd(node)
        cmd_str = " ".join(str(c) for c in cmd)
        assert "pcm_s16le" in cmd_str
        assert "16000" in cmd_str
        assert "pipe:" in cmd_str
        assert "wav" in cmd_str


class TestCompileCmd:
    def test_inserts_global_flags_after_ffmpeg(self, tmp_path):
        import ffmpeg
        node = ffmpeg.input(str(tmp_path / "test.ts")).output(str(tmp_path / "out.ts"))
        cmd = ff.compile_cmd(node)
        assert cmd[0] == "ffmpeg"
        assert cmd[1] == "-hide_banner"
        assert cmd[2] == "-loglevel"
        assert cmd[3] == "warning"


class TestRunAsync:
    @patch("cht.stream.ffmpeg.subprocess.Popen")
    def test_default_no_pipes(self, mock_popen, tmp_path):
        import ffmpeg
        node = ffmpeg.input("test").output("out")
        ff.run_async(node)
        call_kwargs = mock_popen.call_args
        assert call_kwargs.kwargs["stdout"] == subprocess.DEVNULL
        assert call_kwargs.kwargs["stderr"] == subprocess.DEVNULL

    @patch("cht.stream.ffmpeg.subprocess.Popen")
    def test_pipe_stdout(self, mock_popen, tmp_path):
        import ffmpeg
        node = ffmpeg.input("test").output("out")
        ff.run_async(node, pipe_stdout=True)
        call_kwargs = mock_popen.call_args
        assert call_kwargs.kwargs["stdout"] == subprocess.PIPE

    @patch("cht.stream.ffmpeg.subprocess.Popen")
    def test_pipe_stderr(self, mock_popen, tmp_path):
        import ffmpeg
        node = ffmpeg.input("test").output("out")
        ff.run_async(node, pipe_stderr=True)
        call_kwargs = mock_popen.call_args
        assert call_kwargs.kwargs["stderr"] == subprocess.PIPE


class TestRunSync:
    @patch("cht.stream.ffmpeg.subprocess.run")
    def test_returns_tuple(self, mock_run):
        mock_run.return_value = MagicMock(stdout="hello", stderr="world")
        import ffmpeg
        node = ffmpeg.input("test").output("out")
        stdout, stderr = ff.run_sync(node)
        assert stdout == "hello"
        assert stderr == "world"

    @patch("cht.stream.ffmpeg.subprocess.run")
    def test_passes_timeout(self, mock_run):
        mock_run.return_value = MagicMock(stdout="", stderr="")
        import ffmpeg
        node = ffmpeg.input("test").output("out")
        ff.run_sync(node, timeout=30)
        assert mock_run.call_args.kwargs["timeout"] == 30


class TestStopProc:
    def test_sends_sigint_then_waits(self):
        proc = MagicMock()
        proc.poll.return_value = None
        ff.stop_proc(proc, timeout=3)
        proc.send_signal.assert_called_once_with(signal.SIGINT)
        proc.wait.assert_called_once_with(timeout=3)

    def test_kills_on_timeout(self):
        proc = MagicMock()
        proc.poll.return_value = None
        proc.wait.side_effect = subprocess.TimeoutExpired("ffmpeg", 3)
        ff.stop_proc(proc, timeout=3)
        proc.kill.assert_called_once()

    def test_noop_if_already_exited(self):
        proc = MagicMock()
        proc.poll.return_value = 0
        ff.stop_proc(proc)
        proc.send_signal.assert_not_called()

    def test_noop_if_none(self):
        ff.stop_proc(None)  # should not raise