#!/bin/sh
set -eu

BASE_URL="https://umka.day/cli"
INSTALL_DIR="${UMKA_INSTALL_DIR:-$HOME/.umka/bin}"

download() {
	url="$1"
	dest="$2"
	if command -v curl >/dev/null 2>&1; then
		code=$(curl -fsSL -o "$dest" -w '%{http_code}' "$url")
		if [ "$code" != "200" ]; then
			echo "Error: download failed (HTTP $code)" >&2
			echo "URL: $url" >&2
			exit 1
		fi
	elif command -v wget >/dev/null 2>&1; then
		wget -qO "$dest" "$url" || {
			echo "Error: download failed" >&2
			echo "URL: $url" >&2
			exit 1
		}
	else
		echo "Error: curl or wget is required" >&2
		exit 1
	fi
}

main() {
	version="${1:-latest}"

	platform="$(uname -s | tr '[:upper:]' '[:lower:]')"
	arch="$(uname -m)"

	case "$platform" in
		linux)  platform="linux" ;;
		darwin) platform="darwin" ;;
		*)
			echo "Error: unsupported platform: $platform" >&2
			exit 1
			;;
	esac

	case "$arch" in
		x86_64|amd64)   arch="x86_64" ;;
		aarch64|arm64)  arch="aarch64" ;;
		*)
			echo "Error: unsupported architecture: $arch" >&2
			exit 1
			;;
	esac

	binary="umka-${platform}-${arch}"

	echo "Downloading umka (${version}) for ${platform}/${arch}..."

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

	download "${BASE_URL}/${version}/${binary}" "$tmpdir/umka"
	download "${BASE_URL}/${version}/${binary}.sha256" "$tmpdir/umka.sha256"

	expected="$(cat "$tmpdir/umka.sha256" | tr -d '[:space:]')"
	if command -v sha256sum >/dev/null 2>&1; then
		actual="$(sha256sum "$tmpdir/umka" | cut -d' ' -f1)"
	elif command -v shasum >/dev/null 2>&1; then
		actual="$(shasum -a 256 "$tmpdir/umka" | cut -d' ' -f1)"
	else
		echo "Warning: cannot verify checksum (sha256sum/shasum not found)" >&2
		actual="$expected"
	fi

	if [ "$actual" != "$expected" ]; then
		echo "Error: checksum mismatch" >&2
		echo "  expected: $expected" >&2
		echo "  got:      $actual" >&2
		exit 1
	fi

	chmod +x "$tmpdir/umka"

	mkdir -p "$INSTALL_DIR"
	mv "$tmpdir/umka" "$INSTALL_DIR/umka"

	echo "Installed umka to $INSTALL_DIR/umka"

	case ":$PATH:" in
		*":$INSTALL_DIR:"*) ;;
		*)
			echo ""
			echo "Add umka to your PATH:"
			echo "  export PATH=\"$INSTALL_DIR:\$PATH\""
			;;
	esac
}

main "$@"