#!/usr/bin/env bash
# Install fld — FluidDocs CLI
#
# Recommended (public):
#   curl -fsSL https://fluiddocs.ai/install | bash
#
# Pin a versioned host (optional):
#   FLUIDDOCS_INSTALL_BASE=https://fluiddocs.ai bash -s < install.sh
#
# Override install directory:
#   curl -fsSL https://fluiddocs.ai/install | bash -s -- --dir ~/.local/bin
set -euo pipefail

INSTALL_BASE="${FLUIDDOCS_INSTALL_BASE:-https://fluiddocs.ai}"
INSTALL_DIR="${FLUIDDOCS_CLI_INSTALL_DIR:-}"

while [[ $# -gt 0 ]]; do
  case "$1" in
    --dir)
      INSTALL_DIR="${2:-}"
      if [[ -z "$INSTALL_DIR" ]]; then
        echo "Error: --dir requires a path" >&2
        exit 1
      fi
      shift 2
      ;;
    --help|-h)
      echo "Install fld (FluidDocs CLI)"
      echo ""
      echo "Usage: install.sh [--dir DIR]"
      echo ""
      echo "Defaults:"
      echo "  base  \$FLUIDDOCS_INSTALL_BASE or https://fluiddocs.ai"
      echo "  dir   ~/.local/bin (or /usr/local/bin if writable)"
      exit 0
      ;;
    *)
      echo "Unknown option: $1" >&2
      exit 1
      ;;
  esac
done

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

  case "$os" in
    darwin) os="darwin" ;;
    linux) os="linux" ;;
    mingw*|msys*|cygwin*) os="windows" ;;
    *)
      echo "Error: unsupported OS: $(uname -s)" >&2
      exit 1
      ;;
  esac

  case "$arch" in
    x86_64|amd64) arch="x64" ;;
    arm64|aarch64) arch="arm64" ;;
    *)
      echo "Error: unsupported architecture: $arch" >&2
      exit 1
      ;;
  esac

  if [[ "$os" == "windows" ]]; then
    echo "fld-${os}-${arch}.exe"
  else
    echo "fld-${os}-${arch}"
  fi
}

resolve_install_dir() {
  if [[ -n "$INSTALL_DIR" ]]; then
    echo "$INSTALL_DIR"
    return
  fi
  if [[ -d /usr/local/bin && -w /usr/local/bin ]]; then
    echo "/usr/local/bin"
    return
  fi
  echo "${HOME}/.local/bin"
}

need_cmd() {
  if ! command -v "$1" >/dev/null 2>&1; then
    echo "Error: required command not found: $1" >&2
    exit 1
  fi
}

need_cmd curl
need_cmd uname
need_cmd mktemp

# Trim trailing slash
INSTALL_BASE="${INSTALL_BASE%/}"
ASSET="$(detect_asset)"
DEST_DIR="$(resolve_install_dir)"
TMPDIR="$(mktemp -d)"
trap 'rm -rf "$TMPDIR"' EXIT

URL="${INSTALL_BASE}/install/${ASSET}"
OUT="${TMPDIR}/${ASSET}"

echo "Installing fld"
echo "  from: ${URL}"
echo "  into: ${DEST_DIR}/fld"

if ! curl -fsSL "$URL" -o "$OUT"; then
  echo "Error: download failed from ${URL}" >&2
  exit 1
fi

# Reject accidental HTML error pages
if head -c 15 "$OUT" | grep -qi '<!doctype\|<html'; then
  echo "Error: download returned HTML, not a binary (${URL})" >&2
  exit 1
fi

chmod +x "$OUT"
mkdir -p "$DEST_DIR"

if command -v install >/dev/null 2>&1; then
  install -m 755 "$OUT" "${DEST_DIR}/fld"
else
  mv "$OUT" "${DEST_DIR}/fld"
  chmod 755 "${DEST_DIR}/fld"
fi

echo ""
echo "Installed: ${DEST_DIR}/fld"
if ! command -v fld >/dev/null 2>&1; then
  case ":${PATH}:" in
    *":${DEST_DIR}:"*) ;;
    *)
      echo ""
      echo "Add this to your PATH (e.g. in ~/.zshrc):"
      echo "  export PATH=\"${DEST_DIR}:\$PATH\""
      ;;
  esac
fi
echo ""
echo "Try: fld --help"
echo "Then: fld login"