#!/usr/bin/env bash
#
# Cross-compile the sshtools binaries for the three desktop platforms.
#
#   ./build.sh          cross-compile every program and target
#   ./build.sh local    only the host binaries, at dist/golink and dist/goscp
#
# Everything is pure Go (CGO disabled), so no cross toolchain is needed and the
# build works offline: the only dependency, golang.org/x/crypto, is already in
# the local module cache.

set -euo pipefail
cd "$(dirname "${BASH_SOURCE[0]}")"

version="${VERSION:-1.0.0}"
export CGO_ENABLED=0
export GOCACHE="${GOCACHE:-$PWD/.gocache}"
export GOFLAGS="${GOFLAGS:--mod=mod}"

ldflags="-s -w -X main.version=$version"
programs="golink goscp"
targets="linux/amd64 linux/arm64 darwin/amd64 darwin/arm64 windows/amd64 windows/arm64"

mkdir -p dist

build() { # <program> <goos> <goarch> <output>
  GOOS="$2" GOARCH="$3" go build -trimpath -ldflags "$ldflags" -o "$4" "./cmd/$1"
  printf '  %-32s %7s  %s\n' "$4" "$(du -h "$4" | cut -f1)" "$(file -b "$4" 2>/dev/null | cut -c1-58)"
}

hostos="$(go env GOOS)"
hostarch="$(go env GOARCH)"

if [ "${1:-all}" = local ]; then
  for program in $programs; do
    ext=""
    [ "$hostos" = windows ] && ext=".exe"
    build "$program" "$hostos" "$hostarch" "dist/${program}${ext}"
  done
  exit 0
fi

echo "sshtools $version"
for program in $programs; do
  for target in $targets; do
    os="${target%%/*}"
    arch="${target##*/}"
    ext=""
    [ "$os" = windows ] && ext=".exe"
    build "$program" "$os" "$arch" "dist/${program}_${os}_${arch}${ext}"
  done
done

# convenience copies for the machine running this script
ext=""
[ "$hostos" = windows ] && ext=".exe"
for program in $programs; do
  native="dist/${program}_${hostos}_${hostarch}${ext}"
  if [ -f "$native" ]; then
    cp "$native" "dist/${program}${ext}"
  fi
done

echo
( cd dist && sha256sum golink_* goscp_* > SHA256SUMS && cat SHA256SUMS )