"""IMP-49 #78 — partial Figma provenance regression test.

For `templates/phase_z2/families/dx_sw_necessity_three_perspectives.html`,
extract color literals (hex + rgb/rgba, whitespace-preserving) from the
<style> block, then assert each non-whitelisted literal exists byte-identically
in `figma_to_html_agent/blocks/1171281198/index.html`.

Whitelist composition (per Stage 2 EXIT REPORT, IMP-49 #78):
  - Neutrals: #fff, #1a1a1a (page-default text / surface)
  - Shared zone-title token: #000, #883700, rgba(50,44,30,0.4)
    (F13/F14/F12/F11/F18 zone-title family — not sourced from frame 20)

Guardrails:
  - rgb()/rgba() literals matched as substrings, so whitespace (single space
    after comma) is preserved byte-for-byte against upstream.
  - Failure message surfaces the offending literal and the whitelist.
"""
from __future__ import annotations

import re
from pathlib import Path

PROJECT_ROOT = Path(__file__).parent.parent
PARTIAL_PATH = (
    PROJECT_ROOT / "templates" / "phase_z2" / "families"
    / "dx_sw_necessity_three_perspectives.html"
)
UPSTREAM_PATH = (
    PROJECT_ROOT / "figma_to_html_agent" / "blocks" / "1171281198" / "index.html"
)

COLOR_WHITELIST = frozenset({
    "#fff",
    "#1a1a1a",
    "#000",
    "#883700",
    "rgba(50,44,30,0.4)",
})

HEX_RE = re.compile(r"#(?:[0-9a-fA-F]{8}|[0-9a-fA-F]{6}|[0-9a-fA-F]{4}|[0-9a-fA-F]{3})\b")
RGB_RE = re.compile(r"rgba?\([^)]*\)")
STYLE_RE = re.compile(r"<style>(.*?)</style>", re.DOTALL)


def _extract_style_block(html_text: str) -> str:
    match = STYLE_RE.search(html_text)
    assert match, f"partial {PARTIAL_PATH} must contain a <style> block"
    return match.group(1)


def test_partial_color_literals_byte_identical_to_upstream() -> None:
    partial_text = PARTIAL_PATH.read_text(encoding="utf-8")
    upstream_text = UPSTREAM_PATH.read_text(encoding="utf-8")
    css_text = _extract_style_block(partial_text)
    literals = HEX_RE.findall(css_text) + RGB_RE.findall(css_text)
    assert literals, "partial <style> must contain at least one color literal"
    missing = sorted(
        {lit for lit in literals if lit not in COLOR_WHITELIST and lit not in upstream_text}
    )
    assert not missing, (
        "Non-whitelisted color literals in partial must be byte-identical to "
        f"upstream {UPSTREAM_PATH.relative_to(PROJECT_ROOT)}. "
        f"Missing: {missing}. Whitelist: {sorted(COLOR_WHITELIST)}."
    )