install.sh

#!/usr/bin/env bash
# install.sh — Install lean-ctx (download pre-built binary or build from source)
#
# Usage:
#   ./install.sh                # build from source (requires Rust)
#   ./install.sh --download     # download pre-built binary (no Rust needed)
#   ./install.sh --build-only   # build only, don't install
#
# One-liner (no Rust required):
#   curl -fsSL https://leanctx.com/install.sh | sh
set -euo pipefail

REPO="yvgude/lean-ctx"
INSTALL_DIR="${LEAN_CTX_INSTALL_DIR:-$HOME/.local/bin}"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]:-install.sh}")" 2>/dev/null && pwd || pwd)"
RUST_DIR="$SCRIPT_DIR/rust"

echo "lean-ctx installer"
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"

finish() {
  if [[ ":$PATH:" != *":$INSTALL_DIR:"* ]]; then
    echo ""
    echo "Warning: $INSTALL_DIR is not in your PATH."
    local shell_name
    shell_name="$(basename "${SHELL:-bash}" 2>/dev/null || echo bash)"
    local rc="$HOME/.bashrc"
    case "$shell_name" in
      zsh)  rc="$HOME/.zshrc" ;;
      fish) rc="$HOME/.config/fish/config.fish" ;;
    esac
    if [[ "$shell_name" == "fish" ]]; then
      echo "  fish_add_path $INSTALL_DIR"
    else
      echo "  echo 'export PATH=\"\$HOME/.local/bin:\$PATH\"' >> $rc && source $rc"
    fi
  fi
  echo ""
  echo "Done! Verify with: lean-ctx --version"
}

detect_target() {
  local os arch libc
  os="$(uname -s | tr '[:upper:]' '[:lower:]')"
  arch="$(uname -m)"

  case "$arch" in
    x86_64)       arch="x86_64" ;;
    arm64|aarch64) arch="aarch64" ;;
    *)
      echo "Error: unsupported architecture '$arch'"
      echo "Build from source instead: ./install.sh"
      exit 1 ;;
  esac

  case "$os" in
    linux)
      libc="musl"
      if command -v ldd &>/dev/null; then
        local glibc_ver
        glibc_ver="$(ldd --version 2>&1 | head -1 | grep -oE '[0-9]+\.[0-9]+$' || true)"
        if [[ -n "$glibc_ver" ]]; then
          local major minor
          major="${glibc_ver%%.*}"
          minor="${glibc_ver##*.}"
          if [[ "$major" -gt 2 ]] || { [[ "$major" -eq 2 ]] && [[ "$minor" -ge 35 ]]; }; then
            libc="gnu"
          fi
        fi
      fi
      echo "${arch}-unknown-linux-${libc}"
      ;;
    darwin) echo "${arch}-apple-darwin" ;;
    *)
      echo "Error: unsupported OS '$os'"
      echo "Windows: download from https://github.com/${REPO}/releases/latest"
      exit 1 ;;
  esac
}

verify_checksum() {
  local file="$1" expected="$2"
  local actual
  if command -v sha256sum &>/dev/null; then
    actual="$(sha256sum "$file" | cut -d' ' -f1)"
  elif command -v shasum &>/dev/null; then
    actual="$(shasum -a 256 "$file" | cut -d' ' -f1)"
  else
    echo "Warning: no sha256sum/shasum found, skipping checksum verification"
    return 0
  fi

  if [[ "$actual" != "$expected" ]]; then
    echo "Error: checksum mismatch!"
    echo "  Expected: $expected"
    echo "  Got:      $actual"
    exit 1
  fi
  echo "  Checksum verified ✓"
}

install_download() {
  local target
  target="$(detect_target)"
  echo "Mode: download pre-built binary"
  echo "Platform: $target"
  echo ""

  echo "Fetching latest release..."
  local latest
  latest="$(curl -fsSL "https://api.github.com/repos/${REPO}/releases/latest" \
    | grep '"tag_name"' | head -1 | cut -d'"' -f4)"

  if [[ -z "$latest" ]]; then
    echo "Error: could not determine latest release."
    exit 1
  fi
  echo "Latest: $latest"

  local asset_url="https://github.com/${REPO}/releases/download/${latest}/lean-ctx-${target}.tar.gz"
  local sums_url="https://github.com/${REPO}/releases/download/${latest}/SHA256SUMS"

  local tmpdir
  tmpdir="$(mktemp -d)"
  trap 'rm -rf "${tmpdir:-}"' EXIT

  echo "Downloading binary..."
  if ! curl -fsSL "$asset_url" -o "$tmpdir/lean-ctx.tar.gz"; then
    echo "Error: download failed. Check: https://github.com/${REPO}/releases"
    exit 1
  fi

  echo "Downloading checksums..."
  if curl -fsSL "$sums_url" -o "$tmpdir/SHA256SUMS" 2>/dev/null; then
    local expected
    expected="$(grep "lean-ctx-${target}.tar.gz" "$tmpdir/SHA256SUMS" | cut -d' ' -f1)"
    if [[ -n "$expected" ]]; then
      verify_checksum "$tmpdir/lean-ctx.tar.gz" "$expected"
    fi
  else
    echo "  Warning: checksums not available, skipping verification"
  fi

  tar -xzf "$tmpdir/lean-ctx.tar.gz" -C "$tmpdir"

  mkdir -p "$INSTALL_DIR"
  install -m755 "$tmpdir/lean-ctx" "$INSTALL_DIR/lean-ctx"

  if [[ "$(uname -s)" == "Darwin" ]]; then
    xattr -cr "$INSTALL_DIR/lean-ctx" 2>/dev/null || true
    codesign --force --sign - "$INSTALL_DIR/lean-ctx" 2>/dev/null || true
  fi

  echo "  Installed: $INSTALL_DIR/lean-ctx"

  finish
}

install_from_source() {
  if ! command -v cargo &>/dev/null; then
    echo "Error: cargo not found. Install Rust: https://rustup.rs"
    echo "Or download a pre-built binary: $0 --download"
    exit 1
  fi

  local build_only="${1:-}"

  echo "Mode: build from source"
  echo ""
  echo "Building lean-ctx (release)..."

  if [[ -d "$RUST_DIR" ]]; then
    (cd "$RUST_DIR" && cargo build --release)
    local binary="$RUST_DIR/target/release/lean-ctx"
  else
    cargo install lean-ctx
    echo ""
    echo "Installed via cargo install."
    return
  fi

  if [[ ! -x "$binary" ]]; then
    echo "Error: build failed — binary not found"
    exit 1
  fi
  echo "Built: $binary"

  if [[ "$build_only" == "--build-only" ]]; then
    echo "Done (build only)."
    return
  fi

  mkdir -p "$INSTALL_DIR"
  ln -sf "$binary" "$INSTALL_DIR/lean-ctx"
  echo "  Linked: $INSTALL_DIR/lean-ctx -> $binary"

  finish
}

case "${1:-}" in
  --download)    install_download ;;
  --build-only)  install_from_source --build-only ;;
  --help|-h)
    echo "Usage: $0 [--download|--build-only|--help]"
    echo ""
    echo "  (no args)     Build from source (requires Rust)"
    echo "  --download    Download pre-built binary (no Rust needed)"
    echo "  --build-only  Build only, don't install"
    echo ""
    echo "Environment:"
    echo "  LEAN_CTX_INSTALL_DIR  Custom install directory (default: ~/.local/bin)"
    ;;
  *)             install_from_source ;;
esac