"""Regression tests for frontend build configuration.

Prevents re-introducing JS obfuscation plugins that break vendor libraries
(e.g., Mapbox GL WebGL shaders corrupted by string encoding/splitting).
"""
import json
from pathlib import Path

import pytest

FRONTEND_DIR = Path(__file__).resolve().parents[2] / "frontend"

_skip_no_frontend = pytest.mark.skipif(
    not FRONTEND_DIR.is_dir(),
    reason="frontend/ directory not present (e.g. backend-only Docker build)",
)


@_skip_no_frontend
class TestViteConfig:
    """Validate vite.config.ts doesn't contain dangerous build plugins."""

    def test_no_obfuscator_plugin_in_vite_config(self) -> None:
        """JS obfuscation breaks Mapbox GL's WebGL shaders and must not be used.

        vite-plugin-obfuscator processes ALL output chunks (including vendor
        libraries) and corrupts string literals used for WebGL shader source,
        causing the map to render as a blank screen.
        """
        config = (FRONTEND_DIR / "vite.config.ts").read_text()
        assert "obfuscat" not in config.lower(), (
            "vite.config.ts must not use JS obfuscation plugins — "
            "they corrupt Mapbox GL's WebGL shaders and break the map"
        )

    def test_no_obfuscator_in_package_json(self) -> None:
        """Ensure obfuscator packages are not listed as dependencies."""
        pkg = json.loads((FRONTEND_DIR / "package.json").read_text())
        all_deps = {
            **pkg.get("dependencies", {}),
            **pkg.get("devDependencies", {}),
        }
        for dep_name in all_deps:
            assert "obfuscat" not in dep_name.lower(), (
                f"package.json must not include obfuscator packages (found {dep_name})"
            )

    def test_source_maps_disabled(self) -> None:
        """Production builds must not emit source maps."""
        config = (FRONTEND_DIR / "vite.config.ts").read_text()
        assert "sourcemap: false" in config or "sourcemap:false" in config, (
            "vite.config.ts must have sourcemap: false to prevent "
            "shipping .map files in production"
        )