#!/bin/sh
set -eu

release_root="https://memoree.dev/releases"
version="${MEMOREE_VERSION:-}"
install_dir="${MEMOREE_INSTALL_DIR:-}"
temp_dir=""

fail() {
  printf 'memoree installer: %s\n' "$1" >&2
  exit 1
}

cleanup() {
  if [ -n "$temp_dir" ] && [ -d "$temp_dir" ]; then
    rm -rf -- "$temp_dir"
  fi
}
trap cleanup 0
trap 'exit 1' HUP INT TERM

for command_name in curl tar awk uname mktemp mkdir install mv rm grep tr; do
  command -v "$command_name" >/dev/null 2>&1 || fail "$command_name is required"
done

if [ -z "$version" ]; then
  version="$(curl --proto '=https' --tlsv1.2 -sfL "$release_root/latest.txt" | tr -d '\r\n')"
fi
printf '%s' "$version" | grep -Eq '^v[0-9]+\.[0-9]+\.[0-9]+([-.][0-9A-Za-z.-]+)?$' ||
  fail "invalid version: $version"

kernel="$(uname -s)"
machine="$(uname -m)"
case "$kernel:$machine" in
  Darwin:arm64 | Darwin:aarch64) target="aarch64-apple-darwin" ;;
  Darwin:x86_64 | Darwin:amd64) target="x86_64-apple-darwin" ;;
  Linux:aarch64 | Linux:arm64) target="aarch64-unknown-linux-musl" ;;
  Linux:x86_64 | Linux:amd64) target="x86_64-unknown-linux-musl" ;;
  *) fail "unsupported platform: $kernel $machine" ;;
esac

if [ -z "$install_dir" ]; then
  if [ -n "${CARGO_HOME:-}" ]; then
    install_dir="$CARGO_HOME/bin"
  else
    [ -n "${HOME:-}" ] || fail "HOME is required when MEMOREE_INSTALL_DIR is unset"
    install_dir="$HOME/.local/bin"
  fi
fi

archive="memoree-$target.tar.gz"
download_root="$release_root/download/$version"
temp_dir="$(mktemp -d "${TMPDIR:-/tmp}/memoree-install.XXXXXXXX")"
archive_path="$temp_dir/$archive"
checksum_path="$archive_path.sha256"

printf 'Downloading memoree %s for %s...\n' "$version" "$target"
curl --proto '=https' --tlsv1.2 -fsSL --retry 3 -o "$archive_path" "$download_root/$archive"
curl --proto '=https' --tlsv1.2 -fsSL --retry 3 -o "$checksum_path" "$download_root/$archive.sha256"

expected="$(awk 'NR == 1 { print $1 }' "$checksum_path")"
printf '%s' "$expected" | grep -Eq '^[0-9a-fA-F]{64}$' || fail "invalid SHA-256 checksum file"
if command -v sha256sum >/dev/null 2>&1; then
  actual="$(sha256sum "$archive_path" | awk '{ print $1 }')"
elif command -v shasum >/dev/null 2>&1; then
  actual="$(shasum -a 256 "$archive_path" | awk '{ print $1 }')"
else
  fail "sha256sum or shasum is required"
fi
[ "$actual" = "$expected" ] || fail "SHA-256 verification failed"

mkdir -p "$temp_dir/unpack" "$install_dir"
tar -xzf "$archive_path" -C "$temp_dir/unpack"
package_dir="$temp_dir/unpack/memoree-$target"
[ -f "$package_dir/memoree" ] || fail "release archive does not contain memoree"
[ -f "$package_dir/memoree-eval" ] || fail "release archive does not contain memoree-eval"

install -m 755 "$package_dir/memoree" "$install_dir/.memoree.new.$$"
install -m 755 "$package_dir/memoree-eval" "$install_dir/.memoree-eval.new.$$"
mv -f "$install_dir/.memoree.new.$$" "$install_dir/memoree"
mv -f "$install_dir/.memoree-eval.new.$$" "$install_dir/memoree-eval"

printf 'Installed memoree %s to %s\n' "$version" "$install_dir"
printf 'If a daemon is already running, run: memoree daemon restart\n'