from __future__ import annotations

from io import StringIO
from pathlib import Path

from PIL import Image
import pytest
from rich.console import Console
from typer.testing import CliRunner

import kneiff.cli.image as cli_image
from kneiff.utils.image import concat as concat_utils
from kneiff.utils.image import png2jpg as png2jpg_utils
from kneiff.progress import ProgressUpdate
from tests._cli_helpers import invoke_cli


def test_png2jpg_composites_alpha_and_writes_subdirectory(tmp_path: Path) -> None:
    """Cover PNG alpha handling and destination routing."""
    image_path = tmp_path / "source.png"
    image = Image.new("RGBA", (2, 1), color=(255, 0, 0, 128))
    image.save(image_path)

    exit_code = png2jpg_utils.png2jpg(
        tmp_path,
        out_subdir="jpg",
        quality=95,
        subsampling=0,
        bg="#ffffff",
    )

    jpg_path = tmp_path / "jpg" / "source.jpg"
    assert exit_code == 0
    assert jpg_path.exists()
    with Image.open(jpg_path) as converted:
        assert converted.mode == "RGB"
        red, green, blue = converted.getpixel((0, 0))
    assert red > green
    assert red > blue


def test_png2jpg_dry_run_does_not_write_files(tmp_path: Path) -> None:
    """Ensure dry-run mode reports success without touching output."""
    image_path = tmp_path / "source.png"
    Image.new("RGB", (2, 1), color="red").save(image_path)

    exit_code = png2jpg_utils.png2jpg(tmp_path, dry_run=True)

    assert exit_code == 0
    assert not (tmp_path / "jpg" / "source.jpg").exists()


def test_convert_png_jobs_reports_every_status_and_progress(tmp_path: Path) -> None:
    converted_source = tmp_path / "converted.png"
    skipped_source = tmp_path / "skipped.png"
    other_source = tmp_path / "other.png"
    for path in (converted_source, skipped_source, other_source):
        Image.new("RGB", (2, 1), color="red").save(path)

    jobs = png2jpg_utils.discover_png_conversion_jobs(tmp_path, out_subdir="jpg")
    skipped_output = tmp_path / "jpg" / "skipped.jpg"
    skipped_output.parent.mkdir()
    Image.new("RGB", (2, 1), color="blue").save(skipped_output)
    updates: list[ProgressUpdate] = []

    results = png2jpg_utils.convert_png_jobs(
        jobs,
        quality=95,
        subsampling=0,
        bg_rgb=(255, 255, 255),
        overwrite=False,
        dry_run=False,
        progress_callback=updates.append,
    )

    assert [result.status for result in results] == [
        "converted",
        "converted",
        "skipped",
    ]
    assert len(updates) == 3
    assert sum(update.advance for update in updates) == 3


def test_img_png2jpg_redirected_output_keeps_legacy_lines(
    tmp_path: Path,
    isolated_cli_project: Path,
) -> None:
    del isolated_cli_project
    source = tmp_path / "source.png"
    Image.new("RGB", (2, 1), color="red").save(source)

    result = invoke_cli(CliRunner(), ["img", "png2jpg", str(tmp_path)])

    assert result.exit_code == 0, result.output
    assert f"[ok]   {source}  ->  {tmp_path / 'jpg' / 'source.jpg'}" in result.output
    assert "\x1b[" not in result.output


def test_img_png2jpg_terminal_replaces_item_lines_with_progress(
    monkeypatch: pytest.MonkeyPatch,
    tmp_path: Path,
    isolated_cli_project: Path,
) -> None:
    del isolated_cli_project
    source = tmp_path / "source.png"
    Image.new("RGB", (2, 1), color="red").save(source)
    terminal_output = StringIO()
    console = Console(
        file=terminal_output,
        force_terminal=True,
        color_system=None,
        width=100,
    )
    monkeypatch.setattr(cli_image, "stderr_progress_console", lambda: console)

    result = invoke_cli(CliRunner(), ["img", "png2jpg", str(tmp_path)])

    assert result.exit_code == 0, result.output
    assert "[ok]" not in result.output
    assert "PNG conversion complete" in terminal_output.getvalue()
    assert "1/1" in terminal_output.getvalue()


def test_concat_imgs_scales_to_exact_width(tmp_path: Path) -> None:
    """Cover horizontal stacking and rounding drift correction."""
    left = tmp_path / "left.png"
    right = tmp_path / "right.png"
    output = tmp_path / "collage.png"
    Image.new("RGBA", (10, 5), color=(255, 0, 0, 255)).save(left)
    Image.new("RGBA", (20, 10), color=(0, 255, 0, 255)).save(right)

    result = concat_utils.concat_imgs(
        [left, right],
        output=output,
        width=33,
        gap=3,
        bg="transparent",
        align="bottom",
    )

    assert result == output
    with Image.open(output) as collage:
        assert collage.size == (33, 10)