from __future__ import annotations

import shutil

import pytest

from mcp_docugen.docx_renderer import (
    DocxRenderError,
    _preprocess,
    _strip_frontmatter,
    _strip_style_blocks,
    render_markdown_to_docx,
)


def test_strip_style_blocks_removes_simple_block():
    md = "Pre\n<style>h1 { color: red; }</style>\nPost"
    assert "<style>" not in _strip_style_blocks(md)
    assert "color: red" not in _strip_style_blocks(md)


def test_strip_style_blocks_removes_multiline_block_with_attrs():
    md = (
        "Before\n"
        "<style type=\"text/css\">\n"
        "  body { font-family: Inter; }\n"
        "  h1 { color: blue; }\n"
        "</style>\n"
        "After"
    )
    cleaned = _strip_style_blocks(md)
    assert "<style" not in cleaned
    assert "Inter" not in cleaned
    assert "Before" in cleaned and "After" in cleaned


def test_strip_style_blocks_no_style_is_noop():
    md = "# Just markdown\n\nNo style here."
    assert _strip_style_blocks(md) == md


def test_strip_frontmatter_removes_block():
    md = "---\nfoo: bar\npdf_options:\n  format: A4\n---\n\n# Body\n"
    out = _strip_frontmatter(md)
    assert out.startswith("# Body")
    assert "pdf_options" not in out


def test_strip_frontmatter_no_frontmatter_returns_input_unchanged():
    md = "# Body only\n\nText."
    assert _strip_frontmatter(md) == md


def test_strip_frontmatter_unclosed_returns_input_unchanged():
    md = "---\nfoo: bar\nno closing delim"
    assert _strip_frontmatter(md) == md


def test_preprocess_strips_both_frontmatter_and_style():
    md = (
        "---\nfoo: bar\n---\n\n"
        "<style>body { color: red; }</style>\n\n"
        "# Body\n\nContent.\n"
    )
    out = _preprocess(md)
    assert "foo: bar" not in out
    assert "<style>" not in out
    assert "# Body" in out


@pytest.mark.skipif(
    shutil.which("pandoc") is None,
    reason="pandoc binary not available; runs in container or CI with pandoc installed",
)
async def test_render_markdown_to_docx_roundtrip():
    md = (
        "---\nfoo: bar\n---\n\n"
        "<style>h1 { color: red; }</style>\n\n"
        "# Hello\n\n"
        "| A | B |\n|---|---|\n| 1 | 2 |\n\n"
        "**bold** and *italic*.\n"
    )
    result = await render_markdown_to_docx(md)
    # DOCX is a ZIP archive; signature: PK\x03\x04
    assert result.docx_bytes.startswith(b"PK\x03\x04")
    assert result.size_bytes > 1000


async def test_render_empty_markdown_raises():
    with pytest.raises(DocxRenderError):
        await render_markdown_to_docx("")
    with pytest.raises(DocxRenderError):
        await render_markdown_to_docx("   \n\n  ")


async def test_render_only_frontmatter_and_style_raises():
    md = "---\nfoo: bar\n---\n\n<style>h1{}</style>\n\n  \n"
    with pytest.raises(DocxRenderError):
        await render_markdown_to_docx(md)