#!/usr/bin/env python3
"""Draws the README's coverage badge from gcovr's summary.

Usage: scripts/coverage_badge.py <summary.json> <out.svg>
       scripts/coverage_badge.py --plain <label> <value> <out.svg>   any other badge, in blue
Also prints one line, and appends a short table to $GITHUB_STEP_SUMMARY when CI sets it.
"""
import json
import os
import sys


def badge(label, value, color, title):
    left, right = 6 * len(label) + 12, 7 * len(value) + 12
    return f'''<svg xmlns="http://www.w3.org/2000/svg" width="{left + right}" height="20" role="img" aria-label="{label}: {value}">
<title>{title}</title>
<linearGradient id="s" x2="0" y2="100%"><stop offset="0" stop-color="#bbb" stop-opacity=".1"/><stop offset="1" stop-opacity=".1"/></linearGradient>
<clipPath id="r"><rect width="{left + right}" height="20" rx="3" fill="#fff"/></clipPath>
<g clip-path="url(#r)"><rect width="{left}" height="20" fill="#555"/><rect x="{left}" width="{right}" height="20" fill="{color}"/><rect width="{left + right}" height="20" fill="url(#s)"/></g>
<g fill="#fff" text-anchor="middle" font-family="Verdana,Geneva,DejaVu Sans,sans-serif" font-size="11">
<text x="{left / 2}" y="14">{label}</text><text x="{left + right / 2}" y="14">{value}</text></g></svg>
'''


def main():
    if sys.argv[1] == "--plain":  # any other badge: --plain <label> <value> <out.svg>
        label, value, out = sys.argv[2:5]
        open(out, "w").write(badge(label, value, "#007ec6", f"{label}: {value}"))
        return
    summary = json.load(open(sys.argv[1]))
    lines, branches = summary["line_percent"], summary["branch_percent"]
    label, value = "lib coverage", f"{lines:.0f}%"
    color = "#4c1" if lines >= 90 else "#a4a61d" if lines >= 75 else "#dfb317" if lines >= 60 else "#e05d44"
    svg = badge(label, value, color, f"{label}: {value} of the lines of lib/ are run by the host tests")
    open(sys.argv[2], "w").write(svg)
    print(f"coverage of lib/: {lines:.1f}% of {summary['line_total']} lines, {branches:.1f}% of branches, {len(summary['files'])} files")
    step = os.environ.get("GITHUB_STEP_SUMMARY")
    if step:
        worst = sorted((f["line_percent"], f["filename"]) for f in summary["files"] if f["line_total"] >= 10)[:5]
        with open(step, "a") as out:
            out.write(f"### Coverage of `lib/` by the host tests\n\n**{lines:.1f}%** of {summary['line_total']} lines, {branches:.1f}% of branches.\n\n")
            out.write("| Least covered | Lines |\n|---|---|\n" + "".join(f"| `{name}` | {pct:.0f}% |\n" for pct, name in worst))


if __name__ == "__main__":
    main()