#!/usr/bin/env python3
"""Validate the diagram-only fixture contract."""

from __future__ import annotations

import json
import xml.etree.ElementTree as ET
from pathlib import Path

ROOT = Path(__file__).resolve().parent
SVG_NS = {"svg": "http://www.w3.org/2000/svg"}
FORBIDDEN_EFFECTS = (
    "<linearGradient",
    "<radialGradient",
    "<filter",
    "<pattern",
    "feGaussianBlur",
    "drop-shadow",
)
FORBIDDEN_VISIBLE_PHRASES = (
    "핵심 메시지",
    "TECHVIZ · VISUAL GRAMMAR FIXTURE",
    "Pattern 0",
)


def main() -> None:
    directories = sorted(p for p in ROOT.iterdir() if p.is_dir() and len(p.name) > 3 and p.name[:2].isdigit() and p.name[2] == "-")
    if not directories:
        raise SystemExit("no numbered fixture directories found")

    for directory in directories:
        svgs = list(directory.glob("*.svg"))
        if len(svgs) != 1:
            raise SystemExit(f"{directory.name}: expected one SVG, found {len(svgs)}")
        svg_path = svgs[0]
        source = svg_path.read_text(encoding="utf-8")
        root = ET.fromstring(source)
        if root.find("svg:title", SVG_NS) is None or root.find("svg:desc", SVG_NS) is None:
            raise SystemExit(f"{svg_path}: missing SVG title/desc")
        for token in FORBIDDEN_EFFECTS:
            if token in source:
                raise SystemExit(f"{svg_path}: forbidden visual effect {token}")
        for phrase in FORBIDDEN_VISIBLE_PHRASES:
            if phrase in source:
                raise SystemExit(f"{svg_path}: forbidden poster chrome {phrase}")

        composition_path = directory / "composition.json"
        composition = json.loads(composition_path.read_text(encoding="utf-8"))
        if composition.get("diagram_only") is not True:
            raise SystemExit(f"{composition_path}: diagram_only must be true")
        required = {"global title", "footer", "takeaway band", "gradient", "drop shadow", "glow"}
        actual = set(composition.get("forbidden_visible_elements", []))
        missing = required - actual
        if missing:
            raise SystemExit(f"{composition_path}: missing forbidden items {sorted(missing)}")

    print(f"PASS {len(directories)} diagram-only fixtures")


if __name__ == "__main__":
    main()