#!/bin/sh
set -eu

VERSION="${1:?usage: build_speedtest-go.sh <version> [output_dir]}"
OUTPUT_DIR="${2:-$PWD/dist}"
VERSION="${VERSION#v}"
PREFIX_NAME="speedtest-go-${VERSION}-linux-amd64-musl-static"

mkdir -p "$OUTPUT_DIR"

apk add --no-cache   curl   file   go   git   tar   xz

SRCDIR="${TMPDIR:-/tmp}/speedtest-go-src-${VERSION}"
rm -rf "$SRCDIR"
mkdir -p "$SRCDIR"

curl -fsSL "https://github.com/showwin/speedtest-go/archive/refs/tags/v${VERSION}.tar.gz"   | tar -xz -C "$SRCDIR" --strip-components=1

cd "$SRCDIR"
CGO_ENABLED=0 GOARCH=amd64 GOOS=linux   go build     -trimpath     -ldflags="-s -w -extldflags=-static"     -o "$OUTPUT_DIR/$PREFIX_NAME"     .

strip "$OUTPUT_DIR/$PREFIX_NAME" 2>/dev/null || true

(
  cd "$OUTPUT_DIR"
  tar -czf "${PREFIX_NAME}.tar.gz" "$PREFIX_NAME"
  sha256sum "$PREFIX_NAME" "${PREFIX_NAME}.tar.gz" > "${PREFIX_NAME}.sha256"
)

file "$OUTPUT_DIR/$PREFIX_NAME"
ldd "$OUTPUT_DIR/$PREFIX_NAME" || true

if file "$OUTPUT_DIR/$PREFIX_NAME" | grep -qi 'dynamically linked'; then
  echo "error: output binary is still dynamically linked" >&2
  exit 1
fi

echo "build OK: $OUTPUT_DIR/$PREFIX_NAME"