"""Transport for the `visual` domain — args in, delegate, format out."""

from __future__ import annotations

from pathlib import Path

import typer

from tooling.core import cli, console
from tooling.core.command import command
from tooling.core.errors import ReachError
from tooling.domains.visual import blank_check as blank_module
from tooling.domains.visual import diff as diff_module
from tooling.domains.visual import thumbnail as thumbnail_module

app = cli.domain("visual", "Compare captures against goldens, and catch blank ones.")


@app.callback()
def _domain() -> None:
    """Keeps `visual` a group (Typer collapses a single-command app)."""


@app.command("diff")
@command
def diff(
    expected: str = typer.Argument(..., help="Path to the golden PNG."),
    actual: str = typer.Argument(..., help="Path to the captured PNG."),
    tolerance: int = typer.Option(None, "--tolerance", help="Per-channel pixel tolerance."),
    max_diff_pct: float = typer.Option(
        None, "--max-diff-pct", help="Maximum allowed differing percentage."
    ),
    diff_output: str = typer.Option(
        None, "--diff-output", help="Write a PNG highlighting the changed pixels."
    ),
    config: str = typer.Option(None, "--config", help="Path to tests/visual.json."),
) -> None:
    """Pixel-level comparison of a capture against its golden."""
    code = diff_module.run(expected, actual, tolerance, max_diff_pct, diff_output, config)
    if code == 0:
        return
    raise ReachError(
        f"visual-diff: {expected} and {actual} differ beyond the threshold",
        fix="inspect the diff PNG with --diff-output, or update the golden with "
        "make visual-update if the change is intended",
        exit_code=code,
    )


@app.command("blank-check")
@command
def blank_check(
    path: Path = typer.Argument(..., help="The capture to inspect."),
    max_modal: float = typer.Option(
        blank_module.DEFAULT_MAX_MODAL,
        "--max-modal",
        help="Fail above this single-colour fraction.",
    ),
    quiet: bool = typer.Option(False, "--quiet", help="Say nothing when the frame has content."),
) -> None:
    """Fail if a capture is overwhelmingly one colour."""
    code = blank_module.run(path, max_modal, quiet)
    if code == 0:
        return
    raise ReachError(
        f"visual-blank-check: {path} has no content",
        fix="the renderer drew nothing but chrome — check the scenario actually "
        "loaded before recording a golden from this",
        exit_code=code,
    )


@app.command("thumbnail")
@command
def thumbnail(
    target: Path = typer.Argument(..., help="Capture directory, or an image in crop mode."),
    crop: str = typer.Option(None, "--crop", help="Extract this named region instead."),
    config: Path = typer.Option(None, "--config", help="Config JSON path."),
) -> None:
    """Build a contact sheet from a flow capture, or crop a named region."""
    code = thumbnail_module.run(target, crop, config)
    if code == 0:
        console.verdict(f"visual-thumbnail: OK — {target}")
        return
    raise ReachError(
        f"visual-thumbnail: failed for {target}",
        fix="check the target exists and the config names the region you asked for",
        exit_code=code,
    )