#!/bin/sh
set -eu

BASE_URL="${CHORUS_BASE_URL:-https://chorus.host}"
INSTALL_DIR="${CHORUS_INSTALL_DIR:-/usr/local/bin}"
TMP_DIR="$(mktemp -d)"

cleanup() {
  rm -rf "$TMP_DIR"
}
trap cleanup EXIT INT TERM

need() {
  if ! command -v "$1" >/dev/null 2>&1; then
    echo "install.sh: missing required command: $1" >&2
    exit 1
  fi
}

need curl
need tar

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

case "$OS" in
  darwin) OS="darwin" ;;
  linux) OS="linux" ;;
  *) echo "install.sh: unsupported OS: $OS" >&2; exit 1 ;;
esac

case "$ARCH" in
  arm64|aarch64) ARCH="arm64" ;;
  x86_64|amd64) ARCH="amd64" ;;
  *) echo "install.sh: unsupported architecture: $ARCH" >&2; exit 1 ;;
esac

LATEST="$TMP_DIR/latest.json"
curl -fsSL "$BASE_URL/downloads/beacon/latest.json" -o "$LATEST"

VERSION="$(sed -n 's/.*"version"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' "$LATEST" | head -n 1)"
if [ -z "$VERSION" ]; then
  echo "install.sh: could not read version from latest.json" >&2
  exit 1
fi

NAME="beacon-$OS-$ARCH.tar.gz"
URL="$BASE_URL/downloads/beacon/$VERSION/$NAME"
ARCHIVE="$TMP_DIR/$NAME"

curl -fsSL "$URL" -o "$ARCHIVE"
curl -fsSL "$BASE_URL/downloads/beacon/$VERSION/checksums.txt" -o "$TMP_DIR/checksums.txt"

if command -v shasum >/dev/null 2>&1; then
  (cd "$TMP_DIR" && grep "  $NAME\$" checksums.txt | shasum -a 256 -c -)
elif command -v sha256sum >/dev/null 2>&1; then
  (cd "$TMP_DIR" && grep "  $NAME\$" checksums.txt | sha256sum -c -)
else
  echo "install.sh: warning: shasum/sha256sum not found; skipping checksum verification" >&2
fi

tar -xzf "$ARCHIVE" -C "$TMP_DIR"
chmod +x "$TMP_DIR/beacon"

if [ ! -d "$INSTALL_DIR" ]; then
  mkdir -p "$INSTALL_DIR" 2>/dev/null || {
    echo "install.sh: cannot create $INSTALL_DIR; try CHORUS_INSTALL_DIR=\$HOME/.local/bin" >&2
    exit 1
  }
fi

if [ -w "$INSTALL_DIR" ]; then
  mv "$TMP_DIR/beacon" "$INSTALL_DIR/beacon"
else
  sudo mv "$TMP_DIR/beacon" "$INSTALL_DIR/beacon"
fi

echo "Installed beacon $VERSION to $INSTALL_DIR/beacon"