#!/bin/sh
set -e

REPO="host452b/isetup"
INSTALL_DIR="${INSTALL_DIR:-/usr/local/bin}"

# Detect OS
OS=$(uname -s | tr '[:upper:]' '[:lower:]')
case "$OS" in
  darwin|linux) ;;
  *) echo "Unsupported OS: $OS"; exit 1 ;;
esac

# Detect Arch
ARCH=$(uname -m)
case "$ARCH" in
  x86_64|amd64) ARCH="amd64" ;;
  aarch64|arm64) ARCH="arm64" ;;
  *) echo "Unsupported architecture: $ARCH"; exit 1 ;;
esac

# Get latest version
echo "Detecting latest version..."

# Method 1: GitHub API (may hit rate limit without auth)
VERSION=$(curl -fsSL "https://api.github.com/repos/${REPO}/releases/latest" 2>/dev/null | grep '"tag_name"' | head -1 | cut -d'"' -f4 || true)

# Method 2: Follow redirect from /releases/latest to get tag from URL
if [ -z "$VERSION" ]; then
  VERSION=$(curl -fsSI "https://github.com/${REPO}/releases/latest" 2>/dev/null | grep -i '^location:' | grep -oE 'v[0-9]+\.[0-9]+\.[0-9]+' || true)
fi

# Method 3: Hardcoded fallback
if [ -z "$VERSION" ]; then
  VERSION="v0.3.0"
  echo "Could not auto-detect version, using fallback: ${VERSION}"
fi
VERSION_NUM=$(echo "$VERSION" | tr -d 'v')

URL="https://github.com/${REPO}/releases/download/${VERSION}/isetup_${VERSION_NUM}_${OS}_${ARCH}.tar.gz"
echo "Downloading isetup ${VERSION} for ${OS}/${ARCH}..."
echo "  ${URL}"

# Download and extract
TMP=$(mktemp -d)
trap 'rm -rf "$TMP"' EXIT

curl -fsSL "$URL" -o "${TMP}/isetup.tar.gz"

# Verify checksum
CHECKSUM_URL="https://github.com/${REPO}/releases/download/${VERSION}/checksums.txt"
curl -fsSL "$CHECKSUM_URL" -o "${TMP}/checksums.txt" 2>/dev/null || true

if [ -f "${TMP}/checksums.txt" ]; then
  EXPECTED=$(grep "isetup_${VERSION_NUM}_${OS}_${ARCH}.tar.gz" "${TMP}/checksums.txt" | awk '{print $1}')
  if [ -n "$EXPECTED" ]; then
    if command -v sha256sum >/dev/null 2>&1; then
      ACTUAL=$(sha256sum "${TMP}/isetup.tar.gz" | awk '{print $1}')
    elif command -v shasum >/dev/null 2>&1; then
      ACTUAL=$(shasum -a 256 "${TMP}/isetup.tar.gz" | awk '{print $1}')
    fi
    if [ -n "$ACTUAL" ] && [ "$EXPECTED" != "$ACTUAL" ]; then
      echo "ERROR: checksum mismatch!"
      echo "  Expected: $EXPECTED"
      echo "  Got:      $ACTUAL"
      exit 1
    fi
    echo "Checksum verified."
  fi
fi

tar xzf "${TMP}/isetup.tar.gz" -C "$TMP"

# Install
if [ -w "$INSTALL_DIR" ]; then
  mv "${TMP}/isetup" "${INSTALL_DIR}/isetup"
else
  echo "Need sudo to install to ${INSTALL_DIR}"
  sudo mv "${TMP}/isetup" "${INSTALL_DIR}/isetup"
fi

chmod +x "${INSTALL_DIR}/isetup"
echo "Installed isetup ${VERSION} to ${INSTALL_DIR}/isetup"
echo ""
echo "Getting started:"
echo "  isetup install        Pick tools interactively in a terminal, or install all in CI."
echo "  isetup install -i     Force the interactive picker (arrow keys, Space, Enter)."
echo "  isetup list           List profiles and tools without installing anything."
echo "  isetup --help         Full command reference."