"""Unit: the shared renderer's GFM pipe-table pass (phase 44, task 01).

Browser behavior is E2E-covered by ``tests/e2e/test_markdown_tables.py``
(task 03); here we pin the source-level contract — the pass ordering
(fences → tables → escape), the escape-first cell pipeline, the exact
output markers, the placeholder restore, and the ``.md-table`` /
``.md-table-wrap`` CSS rules — so a silent regression is caught without
a browser (the established frontend pattern). A small node-driven
behavioral check (skipped when node is unavailable, like the phase-10
renderer check in ``test_document_viewer.py``) proves the four story
acceptance shapes: table, XSS cell, fence-wins, non-tables stay text.
"""
from __future__ import annotations

import json
import re
import shutil
import subprocess
from pathlib import Path

import pytest

FRONTEND = Path(__file__).resolve().parents[2] / "frontend"
ASSETS = FRONTEND / "assets"
MARKDOWN_JS = ASSETS / "markdown.js"
STYLES_CSS = ASSETS / "styles.css"

HAVE_NODE = shutil.which("node") is not None


def _text(path: Path) -> str:
    assert path.is_file(), f"missing frontend file: {path}"
    return path.read_text(encoding="utf-8")


def _run_node(script: str) -> str:
    proc = subprocess.run(["node", "-e", script], capture_output=True, text=True, timeout=60)
    assert proc.returncode == 0, f"node failed: {proc.stderr}"
    return proc.stdout


# ---------- markdown.js: the table-protection pass ----------


def test_table_pass_runs_after_fences_and_before_escape() -> None:
    """The renderer's pass order is fences → tables → escape (story AC3:
    a |-heavy fenced block is protected before the table pass ever sees
    it, so fences win). Pinned by the placeholder-emission order in the
    source: the \\u0000CODEn\\u0000 push (step 1) precedes the
    \\u0000TABLEn\\u0000 push (step 1b), which precedes step 2's
    escape of the whole text."""
    js = _text(MARKDOWN_JS)
    fence_emit = r"\u0000CODE${codeBlocks.length - 1}\u0000"
    table_emit = r"\u0000TABLE${tables.length - 1}\u0000"
    assert fence_emit in js, "the fence pass keeps its CODE placeholder"
    assert table_emit in js, "the table pass emits a TABLE placeholder"
    assert js.find(fence_emit) < js.find(table_emit), (
        "the fence pass must run BEFORE the table pass (fences win)"
    )
    assert "escapeHtml(text)" in js, "step 2 still escapes the whole text"
    assert js.find(table_emit) < js.find("escapeHtml(text)"), (
        "the table pass must run BEFORE the escape pass (cells are escaped per-cell)"
    )


def test_table_detection_requires_pipe_header_then_separator() -> None:
    """Detection (per the phase spec): a table block starts at a line
    containing '|' whose NEXT line is a separator — >=1 pipe-separated
    cells, each ^\\s*:?-+:?\\s*$ (leading/trailing pipes allowed) — and
    extends over every following line that still contains '|'; the
    maximal run is one table. Everything else is left untouched."""
    js = _text(MARKDOWN_JS)
    # the separator cell rule (alignment colons accepted, then ignored)
    assert r"^\s*:?-+:?\s*$" in js, "the separator cell rule ^\\s*:?-+:?\\s*$ is missing"
    # a table starts at a '|' line whose NEXT line is the separator
    assert 'line.includes("|")' in js, "the header line must contain '|'"
    assert "isSeparator(tableLines[pos + 1])" in js, (
        "the NEXT line after the '|' line must be the separator"
    )
    # the body extends over every following line that still contains '|'
    assert 'tableLines[end].includes("|")' in js, (
        "the table body must extend over every following line containing '|'"
    )
    # zero body rows is valid — body = the lines after header + separator
    assert "slice(2)" in js, "body rows are the lines after header + separator"


def test_cells_are_escaped_then_inline_transformed() -> None:
    """Escape-first is the renderer invariant: each cell (header AND
    body) goes through escapeHtml() BEFORE the inline transforms, and
    the inline chain is the SAME factored helper the whole-text path
    uses — so cells keep `code` / **bold** / *em* exactly like prose."""
    js = _text(MARKDOWN_JS)
    assert js.count("inline(escapeHtml(c))") >= 2, (
        "header and body cells must both run inline(escapeHtml(cell))"
    )
    # the whole-text path runs the same helper over the escaped text
    assert "text = inline(escapeHtml(text));" in js, (
        "step 2 must reuse the SAME factored inline chain"
    )
    # the helper carries the exact original .replace chain
    helper_start = js.find("const inline = (s) =>")
    assert helper_start != -1, "the inline chain must be factored into a local helper"
    helper = js[helper_start : js.find(";", js.find("gm", helper_start)) + 1]
    for marker in (
        r"/`([^`\n]+)`/g",
        r"\*\*([^*]+)\*\*",
        r"(^|[\s(])\*([^*\n]+)\*",
        r"/^### (.*)$/gm",
        r"/^## (.*)$/gm",
        r"/^# (.*)$/gm",
        r"/^\s*[-*] (.*)$/gm",
        r"(<li>[\s\S]*?<\/li>)(?!\s*<li>)",
        r"/^\d+\. (.*)$/gm",
    ):
        assert marker in helper, f"the factored helper lost the {marker!r} step"
    assert js.count("replace(/`([^`\\n]+)`/g") == 1, (
        "the code-span replace must live ONLY in the factored helper"
    )


def test_table_output_markers_and_wrap() -> None:
    """The exact output shape the story pins: a semantic table inside a
    horizontal-overflow wrapper — <div class=\"md-table-wrap\"> /
    <table class=\"md-table\"> / <thead> with th scope=\"col\" headers /
    <tbody> body rows (a header-only table omits the empty <tbody>)."""
    js = _text(MARKDOWN_JS)
    assert '<div class="md-table-wrap">' in js
    assert '<table class="md-table">' in js
    assert "<thead><tr>" in js
    assert '<th scope="col">' in js, "headers must carry scope=\"col\""
    assert "</thead>" in js and "</table>" in js and "</div>" in js
    assert "<tbody>" in js and "</tbody>" in js
    assert "<td>" in js and "</tr>" in js
    # header-only tables: the tbody is conditional on having body rows
    assert re.search(r"body\s*\?", js), "a header-only table must skip the <tbody>"
    # the assembly order inside the push template: wrap, table, thead,
    # (tbody), close — pinned on the quoted source literals (the header
    # comment mentions the shapes out of order on purpose)
    wrap_lit = "'<div class=\"md-table-wrap\">\\n'"
    table_lit = "'<table class=\"md-table\">\\n'"
    assert js.find(wrap_lit) != -1, "the template must open the .md-table-wrap div"
    assert js.find(table_lit) != -1, "the template must open the table inside the wrap"
    assert js.find(wrap_lit) < js.find(table_lit), "the wrap opens before the table"
    assert '</table>\\n</div>' in js, "the template closes the table, then the wrap"


def test_header_and_body_rows_pad_and_truncate_to_header_width() -> None:
    """Defensive ragged rows: short rows are padded with empty <td>s,
    long rows are truncated to the header width (mock and real answers
    are well-formed; this only guards the parser)."""
    js = _text(MARKDOWN_JS)
    assert re.search(r"cells\.push\(\"\"\)", js), "short rows must be padded"
    assert re.search(r"slice\(0,\s*width\)", js), "long rows must be truncated"
    assert "const width = header.length;" in js, "the header row sets the column count"


def test_placeholder_restored_alongside_code_blocks() -> None:
    """Step 4 is the ONLY place placeholders re-expand — the TABLE
    placeholders are restored there, next to the CODE ones, so the
    final table HTML never re-enters the escape/paragraph passes."""
    js = _text(MARKDOWN_JS)
    fn = js.find("function renderMarkdown")
    assert fn != -1
    body = js[fn:]
    # step 4 is the ONLY restore point and it restores BOTH placeholder
    # kinds, indexing their arrays
    assert r"\u0000TABLE(\d+)\u0000/g" in body, (
        "step 4 must restore the \\u0000TABLEn\\u0000 placeholders"
    )
    assert "tables[Number(i)]" in body, "restoration must index the tables array"
    assert r"\u0000CODE(\d+)\u0000/g" in body, "the CODE restore stays in step 4"
    # the TABLE restore is AFTER the paragraph pass — the restored final
    # HTML never re-enters it
    assert body.find(r"\u0000TABLE(\d+)\u0000/g") > body.find("split(/\\n{2,}/)"), (
        "placeholders are restored AFTER the paragraph pass"
    )


def test_alignment_colons_are_parsed_but_ignored() -> None:
    """Owner decision (2026-08-27): the separator's alignment colons
    match the cell rule (so ':---:' is a valid separator) but are never
    turned into CSS alignment — the CSS pins every cell to left."""
    js = _text(MARKDOWN_JS)
    assert r"^\s*:?-+:?\s*$" in js, "colons must be accepted in separators"
    css = _text(STYLES_CSS)
    th_td = re.search(r"\.md-table th, .md-table td \{([^}]*)\}", css)
    assert th_td, "styles.css must style .md-table th/td"
    assert "text-align: left" in th_td.group(1), "all cells render left-aligned"


def test_header_comment_notes_the_table_pass() -> None:
    """The file's header comment records the extension (2026-08-27,
    TODO.md L6) — the ~60-line no-CDN renderer now also does tables."""
    header = _text(MARKDOWN_JS).split("*/", 1)[0]
    assert "Phase 44" in header
    assert "2026-08-27" in header
    assert "TODO.md L6" in header
    assert re.search(r"table", header, re.I), "the header comment must mention tables"
    assert "no CDN" in header, "the no-CDN contract stays stated (A11)"


# ---------- styles.css: the .md-table / .md-table-wrap rules ----------


def test_table_wrap_is_the_horizontal_scroller() -> None:
    """.md-table-wrap { overflow-x: auto } — the wrapper (not the
    table) is the scroller, so a wide table scrolls inside the bubble
    instead of breaking the 46rem column (story AC5)."""
    css = _text(STYLES_CSS)
    block = re.search(r"\.md-table-wrap\s*\{([^}]*)\}", css)
    assert block, "styles.css must define .md-table-wrap"
    assert re.search(r"overflow-x:\s*auto", block.group(1)), (
        "the wrapper must scroll horizontally"
    )


def test_table_rule_and_cell_borders_use_the_palette() -> None:
    """.md-table is border-collapse, full-width (min-width: max-content
    keeps a wide table at its natural width so the wrap scrolls — phase
    44 task 03), 0.9rem; th/td carry the --line 1px borders, 0.4rem
    0.6rem padding, left alignment, top vertical alignment; the thead is
    tinted from the PLAIN surface family (PLAN §7.2: --ink on --surface
    is 14.5:1) — never the brand tokens."""
    css = _text(STYLES_CSS)
    table = re.search(r"(?<![-\w])\.md-table\s*\{([^}]*)\}", css)
    assert table, "styles.css must define .md-table"
    body = table.group(1)
    assert re.search(r"border-collapse:\s*collapse", body)
    assert re.search(r"width:\s*100%", body), "narrow tables stretch to the column"
    assert re.search(r"min-width:\s*max-content", body), (
        "wide tables must keep their natural width so .md-table-wrap scrolls"
    )
    assert re.search(r"font-size:\s*0\.9rem", body)
    cells = re.search(r"\.md-table th, .md-table td\s*\{([^}]*)\}", css)
    assert cells, "styles.css must style .md-table th and td"
    cell_body = cells.group(1)
    assert re.search(r"border:\s*1px solid var\(--line\)", cell_body), (
        "cells must carry the quiet --line hairline borders"
    )
    assert re.search(r"padding:\s*0\.4rem 0\.6rem", cell_body)
    assert re.search(r"text-align:\s*left", cell_body)
    assert re.search(r"vertical-align:\s*top", cell_body)
    thead = re.search(r"\.md-table thead th\s*\{([^}]*)\}", css)
    assert thead, "styles.css must tint the thead cells"
    thead_body = thead.group(1)
    assert "var(--surface)" in thead_body, "thead tint is the plain surface family"
    assert "var(--ink)" in thead_body, "--ink on --surface is 14.5:1 (>= 4.5:1)"
    assert "--brand" not in thead_body, "never the brand tokens on the thead"


def test_table_rules_carry_no_motion() -> None:
    """Reduced-motion consistency: the table rules are static content —
    no animation/transition for prefers-reduced-motion to still (the
    phase-44 comment states this, like the phase-08/22/36 static
    components)."""
    css = _text(STYLES_CSS)
    rules = (
        r"\.md-table-wrap",
        r"(?<![-\w])\.md-table",
        r"\.md-table th, .md-table td",
        r"\.md-table thead th",
    )
    for name in rules:
        block = re.search(name + r"\s*\{([^}]*)\}", css)
        assert block, f"styles.css must define {name}"
        assert "animation" not in block.group(1), f"{name} must not animate"
        assert "transition" not in block.group(1), f"{name} must not transition"
    assert re.search(r"nothing for\s+prefers-reduced-motion to still", css), (
        "the table block comment must note there is nothing to still"
    )


def test_table_css_lives_with_the_bubble_markdown_rules() -> None:
    """Placement (task 01 step 2): the table rules sit with the
    markdown/content styling — right after the .bubble code rules,
    before the .msg.user block — and are unscoped so the shared
    renderer's tables in the thinking scratchpad and the document
    viewer (.doc-md) get the same treatment."""
    css = _text(STYLES_CSS)
    assert css.find('.bubble pre code {') < css.find(".md-table-wrap"), (
        "the table rules follow the bubble markdown content rules"
    )
    assert css.find(".md-table thead th") < css.find(".msg.user {"), (
        "the table rules stay in the Messages section"
    )
    # no .bubble-scoped table variant: one rule set serves all consumers
    assert re.search(r"\.bubble\s+\.md-table", css) is None, (
        "the table rules must be unscoped (shared renderer consumers)"
    )


# ---------- behavior (node): the story's acceptance shapes ----------


@pytest.mark.skipif(not HAVE_NODE, reason="node not available")
def test_table_renders_semantic_xss_safe_and_fences_win() -> None:
    """The four story shapes executed under node: (1) a pipe table with
    leading/trailing pipes + inline markdown in cells renders the
    <div class=\"md-table-wrap\"><table class=\"md-table\"> shape with
    <th scope=\"col\"> headers and padded ragged rows, and NO raw
    separator line survives; (2) a cell with an HTML tag is escaped;
    (3) a |-heavy fenced block stays <pre><code>; (4) a lone pipe in
    prose, a separator without a header, and a 1-line 'table' stay
    text."""
    js = _text(MARKDOWN_JS)
    cases = {
        "table": (
            "Here:\n\n| Service | Port |\n|:---|---:|\n| **api** | 8000 |\n| web |",
            [
                '<div class="md-table-wrap">',
                '<table class="md-table">',
                "<thead><tr><th scope=\"col\">Service</th><th scope=\"col\">Port</th></tr></thead>",
                "<tbody><tr><td><strong>api</strong></td><td>8000</td></tr>"
                "<tr><td>web</td><td></td></tr></tbody>",
                "</table>\n</div>",
            ],
            ["|:---|---:|", "| **api** |"],
        ),
        "xss": (
            "| c |\n|---|\n| <img src=x onerror=alert(1)> & co |",
            ["&lt;img src=x onerror=alert(1)&gt; &amp; co"],
            ["<img"],
        ),
        "fence": (
            "```\n| a | b |\n|---|---|\n| 1 | 2 |\n```",
            ["<pre><code>| a | b |"],
            ["<table"],
        ),
        "not_tables": (
            "a | b prose\n\n---\n\n| only a line\n\nend |---|",
            ["<p>a | b prose</p>", "<p>---</p>", "<p>| only a line</p>", "<p>end |---|</p>"],
            ["<table"],
        ),
    }
    driver = (
        js
        + "\nconst out = {}; "
        + "".join(
            f"out.{name} = renderMarkdown({value!r}); " for name, (value, _, _) in cases.items()
        )
        + "console.log(JSON.stringify(out));"
    )
    results = json.loads(_run_node(driver))
    for name, (_, must_contain, must_not) in cases.items():
        html = results[name]
        for marker in must_contain:
            assert marker in html, f"{name}: missing {marker!r} in {html!r}"
        for marker in must_not:
            assert marker not in html, f"{name}: unexpected {marker!r} in {html!r}"