#!/bin/sh
# Install the latest clawx release from GitHub.
#
#   curl -fsSL https://raw.githubusercontent.com/debarshibasak/clawx/master/install.sh | sh
#
# Environment overrides:
#   CLAWX_VERSION      release tag to install (default: latest release)
#   CLAWX_INSTALL_DIR  destination directory (default: /usr/local/bin, falling
#                      back to ~/.local/bin when /usr/local/bin is not writable)
set -eu

REPO="debarshibasak/clawx"
BINARY="clawx"

fail() {
	echo "error: $*" >&2
	exit 1
}

os=$(uname -s)
case "$os" in
Darwin) os=darwin ;;
Linux) os=linux ;;
*) fail "unsupported OS '$os' — download an archive manually from https://github.com/$REPO/releases" ;;
esac

arch=$(uname -m)
case "$arch" in
x86_64) arch=amd64 ;;
arm64 | aarch64) arch=arm64 ;;
*) fail "unsupported architecture '$arch'" ;;
esac

version=${CLAWX_VERSION:-}
if [ -z "$version" ]; then
	version=$(curl -fsSL "https://api.github.com/repos/$REPO/releases/latest" |
		sed -n 's/.*"tag_name"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' | head -n 1)
	[ -n "$version" ] || fail "could not resolve the latest release tag from the GitHub API"
fi

archive="${BINARY}_${version}_${os}_${arch}.tar.gz"
base="https://github.com/$REPO/releases/download/$version"

tmp=$(mktemp -d)
trap 'rm -rf "$tmp"' EXIT

echo "downloading $archive ($version)"
curl -fsSL -o "$tmp/$archive" "$base/$archive"
curl -fsSL -o "$tmp/checksums.txt" "$base/checksums.txt"

grep " $archive\$" "$tmp/checksums.txt" >"$tmp/checksum.txt" ||
	fail "$archive not found in checksums.txt"
if command -v sha256sum >/dev/null 2>&1; then
	(cd "$tmp" && sha256sum -c checksum.txt >/dev/null) || fail "SHA256 verification failed for $archive"
else
	(cd "$tmp" && shasum -a 256 -c checksum.txt >/dev/null) || fail "SHA256 verification failed for $archive"
fi

tar -xzf "$tmp/$archive" -C "$tmp"

dest=${CLAWX_INSTALL_DIR:-}
sudo=""
if [ -z "$dest" ]; then
	if [ -w /usr/local/bin ]; then
		dest=/usr/local/bin
	elif command -v sudo >/dev/null 2>&1 && [ -t 0 ]; then
		dest=/usr/local/bin
		sudo=sudo
	else
		dest="$HOME/.local/bin"
	fi
fi
mkdir -p "$dest" 2>/dev/null || $sudo mkdir -p "$dest"

$sudo install -m 0755 "$tmp/$BINARY" "$dest/$BINARY"

echo "installed $BINARY $version to $dest/$BINARY"
case ":$PATH:" in
*":$dest:"*) ;;
*) echo "warning: $dest is not on your PATH" >&2 ;;
esac