from fastapi import APIRouter, Query, HTTPException
from fastapi.responses import JSONResponse
from pathlib import Path
import xml.etree.ElementTree as ET

router = APIRouter(prefix="/badge", tags=["coverage", "badge"])


# ---------- Helper functions ----------

def parse_coverage_percentage(coverage_file: Path) -> float:
    """Parse the overall coverage percentage from coverage.xml."""
    tree = ET.parse(coverage_file)
    root = tree.getroot()
    line_rate = float(root.attrib.get("line-rate", 0))
    return round(line_rate * 100, 2)


def get_color(pct: float) -> str:
    """Return badge color based on coverage."""
    if pct >= 90:
        return "brightgreen"
    if pct >= 75:
        return "green"
    if pct >= 60:
        return "yellow"
    if pct >= 40:
        return "orange"
    return "red"


# ---------- Route ----------
@router.get("/{project}", response_class=JSONResponse)
async def get_coverage_badge(project: str):
    """
    Return a Shields.io-compatible badge JSON for the given project's coverage.

    Example:
        /coverage/badge?project=mongo-ops

    Use with Shields.io:
        https://img.shields.io/endpoint?url=https://api.aetoskia.com/coverage/mongo-ops/badge
    """
    project_dir = Path.cwd() / project
    coverage_file = project_dir / "coverage.xml"

    if not coverage_file.exists():
        raise HTTPException(status_code=404, detail=f"No coverage.xml found in '{project}'")

    pct = parse_coverage_percentage(coverage_file)

    return {
        "schemaVersion": 1,
        "label": f"{project} coverage",
        "message": f"{pct}%",
        "color": get_color(pct),
    }