"""
Deterministic SVG to High-Resolution PNG Export Pipeline
Renders docs/diagram-alur.svg to docs/diagram-alur.png at 3840x2160 (4K UHD)
using Playwright Chromium with device_scale_factor=2.0.

Usage:
    uv run python scripts/export_diagram_png.py
"""

import asyncio
from pathlib import Path
from playwright.async_api import async_playwright
from PIL import Image


async def export_svg_to_png(
    svg_path: Path,
    png_path: Path,
    width: int = 1920,
    height: int = 1080,
    scale: float = 2.0
) -> None:
    if not svg_path.exists():
        raise FileNotFoundError(f"SVG file not found: {svg_path}")

    svg_content = svg_path.read_text(encoding="utf-8")

    async with async_playwright() as p:
        browser = await p.chromium.launch()
        page = await browser.new_page(
            viewport={"width": width, "height": height},
            device_scale_factor=scale
        )
        html_wrapper = f"""<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<style>
  * {{ box-sizing: border-box; margin: 0; padding: 0; }}
  html, body {{ width: 100vw; height: 100vh; overflow: hidden; background-color: #080c14; }}
  svg {{ display: block; width: 100%; height: 100%; }}
</style>
</head>
<body>{svg_content}</body>
</html>"""
        await page.set_content(html_wrapper)
        # Ensure all drop shadows and fonts settle
        await page.wait_for_timeout(350)
        png_bytes = await page.screenshot(type="png")
        await browser.close()

    png_path.parent.mkdir(parents=True, exist_ok=True)
    png_path.write_bytes(png_bytes)

    # Verification
    with Image.open(png_path) as img:
        w, h = img.size
        mode = img.mode
        file_size_kb = len(png_bytes) / 1024
        print(f"Exported PNG successfully: {png_path}")
        print(f"Dimensions: {w}x{h} px | Mode: {mode} | Size: {file_size_kb:.1f} KB")
        assert w >= 2400 and h >= 1350, f"Resolution check failed: {w}x{h}"
        assert w == 3840 and h == 2160, f"Expected 3840x2160, got {w}x{h}"


def main():
    root = Path(__file__).resolve().parent.parent
    svg_file = root / "docs" / "diagram-alur.svg"
    png_file = root / "docs" / "diagram-alur.png"
    print(f"Rendering SVG from: {svg_file}")
    print(f"Target PNG: {png_file}")
    asyncio.run(export_svg_to_png(svg_file, png_file, scale=2.0))


if __name__ == "__main__":
    main()