from __future__ import annotations

import shutil
from pathlib import Path
from typing import Iterable

from dominate import document
from dominate.tags import a, i, img, table, td, th, tr
from PIL import Image

from ..common import UI_TESTS_DIR

_IMAGE_DIR = UI_TESTS_DIR / "images"


def set_image_dir(path: Path) -> None:
    global _IMAGE_DIR
    _IMAGE_DIR = path


def store_images(screens: Iterable[Path], hashes: Iterable[str]) -> None:
    for screen, hash in zip(screens, hashes):
        shutil.copy(screen, _IMAGE_DIR / f"{hash}.png")


def report_links(
    tests: list[Path], reports_path: Path, actual_hashes: dict[str, str] | None = None
) -> None:
    if actual_hashes is None:
        actual_hashes = {}

    if not tests:
        i("None!")
        return
    with table(border=1):
        with tr():
            th("Link to report")
        for test in sorted(tests):
            with tr(data_actual_hash=actual_hashes.get(test.stem, "")):
                path = test.relative_to(reports_path)
                td(a(test.name, href=path))


def write(fixture_test_path: Path, doc: document, filename: str) -> Path:
    (fixture_test_path / filename).write_text(doc.render())
    return fixture_test_path / filename


def image_column(hash: str | None, cur_dir: Path) -> None:
    """Put image into table as one cell."""
    with td():
        if hash:
            image_link(hash, cur_dir)
        else:
            i("missing")


def _relative_path(cur_dir: Path, path_to: Path) -> str:
    """Find best relative path to refer to path_to from cur_dir."""
    cur_dir = cur_dir.resolve()
    path_to = path_to.resolve()
    if not cur_dir.is_dir():
        cur_dir = cur_dir.parent

    common = cur_dir
    while common not in path_to.parents:
        common = common.parent
    ascent = len(cur_dir.parts) - len(common.parts)
    relpath = path_to.relative_to(common)
    components = [".."] * ascent + list(relpath.parts)
    return "/".join(components)


def image_link(hash: str, cur_dir: Path, title: str = "") -> None:
    """Put image into table as one cell."""
    path = _IMAGE_DIR / f"{hash}.png"
    im = Image.open(path)
    width = im.width
    if width < 240:
        width *= 2

    img(
        src=_relative_path(cur_dir, path),
        style=f"width: {width}px; image-rendering: pixelated;",
        title=title,
        loading="lazy",
    )


def diff_table(diff: Iterable[tuple[str | None, str | None]], cur_dir: Path) -> None:
    for left, right in diff:
        if left == right:
            background = "white"
        else:
            background = "red"
        with tr(bgcolor=background):
            image_column(left, cur_dir)
            image_column(right, cur_dir)