#!/usr/bin/env bash
#
# atai CLI installer
#
# Usage:
#   curl -fsSL https://cli.archetypeai.app/install.sh | bash
#   curl -fsSL https://cli.archetypeai.app/install.sh | bash -s -- --version 0.2.0
#   curl -fsSL https://cli.archetypeai.app/install.sh | INSTALL_DIR=~/.local/bin bash
#
set -euo pipefail

# ---------------------------------------------------------------------------
# Configuration
# ---------------------------------------------------------------------------
BASE_URL="${ATAI_CLI_BASE_URL:-https://cli.archetypeai.app}"
INSTALL_DIR="${INSTALL_DIR:-/usr/local/bin}"
BINARY_NAME="atai"
VERSION="${ATAI_CLI_VERSION:-latest}"

# ---------------------------------------------------------------------------
# Parse arguments
# ---------------------------------------------------------------------------
while [[ $# -gt 0 ]]; do
  case "$1" in
    --version|-v)
      VERSION="$2"
      shift 2
      ;;
    --install-dir|-d)
      INSTALL_DIR="$2"
      shift 2
      ;;
    --help|-h)
      echo "atai CLI installer"
      echo ""
      echo "Usage: curl -fsSL ${BASE_URL}/install.sh | bash"
      echo ""
      echo "Options:"
      echo "  --version, -v      Version to install (default: latest)"
      echo "  --install-dir, -d  Installation directory (default: /usr/local/bin)"
      echo ""
      echo "Environment variables:"
      echo "  INSTALL_DIR          Override install directory"
      echo "  ATAI_CLI_VERSION     Override version"
      echo "  ATAI_CLI_BASE_URL    Override download base URL"
      exit 0
      ;;
    *)
      echo "Unknown option: $1"
      exit 1
      ;;
  esac
done

# ---------------------------------------------------------------------------
# Detect platform
# ---------------------------------------------------------------------------
detect_os() {
  local os
  os="$(uname -s)"
  case "$os" in
    Linux)  echo "linux" ;;
    Darwin) echo "darwin" ;;
    *)
      echo "Error: Unsupported operating system: $os" >&2
      echo "atai CLI supports Linux and macOS." >&2
      exit 1
      ;;
  esac
}

detect_arch() {
  local arch
  arch="$(uname -m)"
  case "$arch" in
    x86_64|amd64)   echo "x86_64" ;;
    aarch64|arm64)   echo "arm64" ;;
    *)
      echo "Error: Unsupported architecture: $arch" >&2
      echo "atai CLI supports x86_64 and arm64." >&2
      exit 1
      ;;
  esac
}

OS="$(detect_os)"
ARCH="$(detect_arch)"
ARTIFACT="atai-${OS}-${ARCH}"

# ---------------------------------------------------------------------------
# Download
# ---------------------------------------------------------------------------
DOWNLOAD_URL="${BASE_URL}/${VERSION}/${ARTIFACT}"
CHECKSUM_URL="${BASE_URL}/${VERSION}/${ARTIFACT}.sha256"
TMP_DIR="$(mktemp -d)"

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

echo "==> Downloading atai CLI for ${OS}/${ARCH}..."
echo "    ${DOWNLOAD_URL}"

if command -v curl &>/dev/null; then
  curl -fsSL -o "${TMP_DIR}/${BINARY_NAME}" "$DOWNLOAD_URL"
  curl -fsSL -o "${TMP_DIR}/${BINARY_NAME}.sha256" "$CHECKSUM_URL" 2>/dev/null || true
elif command -v wget &>/dev/null; then
  wget -qO "${TMP_DIR}/${BINARY_NAME}" "$DOWNLOAD_URL"
  wget -qO "${TMP_DIR}/${BINARY_NAME}.sha256" "$CHECKSUM_URL" 2>/dev/null || true
else
  echo "Error: curl or wget is required to download atai CLI." >&2
  exit 1
fi

# ---------------------------------------------------------------------------
# Verify checksum
# ---------------------------------------------------------------------------
if [ -f "${TMP_DIR}/${BINARY_NAME}.sha256" ] && [ -s "${TMP_DIR}/${BINARY_NAME}.sha256" ]; then
  echo "==> Verifying checksum..."
  EXPECTED="$(awk '{print $1}' "${TMP_DIR}/${BINARY_NAME}.sha256")"
  if command -v sha256sum &>/dev/null; then
    ACTUAL="$(sha256sum "${TMP_DIR}/${BINARY_NAME}" | awk '{print $1}')"
  elif command -v shasum &>/dev/null; then
    ACTUAL="$(shasum -a 256 "${TMP_DIR}/${BINARY_NAME}" | awk '{print $1}')"
  else
    echo "    Warning: sha256sum/shasum not found, skipping verification." >&2
    ACTUAL="$EXPECTED"
  fi

  if [ "$EXPECTED" != "$ACTUAL" ]; then
    echo "Error: Checksum verification failed!" >&2
    echo "  Expected: $EXPECTED" >&2
    echo "  Actual:   $ACTUAL" >&2
    exit 1
  fi
  echo "    Checksum OK."
else
  echo "    Warning: Checksum file not available, skipping verification."
fi

# ---------------------------------------------------------------------------
# Install
# ---------------------------------------------------------------------------
chmod +x "${TMP_DIR}/${BINARY_NAME}"

echo "==> Installing to ${INSTALL_DIR}/${BINARY_NAME}..."

# Create install dir if it doesn't exist
if [ ! -d "$INSTALL_DIR" ]; then
  mkdir -p "$INSTALL_DIR" 2>/dev/null || sudo mkdir -p "$INSTALL_DIR"
fi

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

# ---------------------------------------------------------------------------
# Verify installation
# ---------------------------------------------------------------------------
echo ""
echo "atai CLI installed successfully!"
echo ""

if command -v "$BINARY_NAME" &>/dev/null; then
  echo "  Location: $(command -v "$BINARY_NAME")"
  "$BINARY_NAME" --version 2>/dev/null || true
else
  echo "  Installed to: ${INSTALL_DIR}/${BINARY_NAME}"
  echo ""
  echo "  Note: ${INSTALL_DIR} is not in your PATH."
  echo "  Add it with:"
  echo ""
  echo "    export PATH=\"${INSTALL_DIR}:\$PATH\""
  echo ""
fi