#!/bin/sh
# PersistMemory CLI installer.
#
#   curl -fsSL https://persistmemory.com/install.sh | sh
#
# Read it first if you would rather:
#   curl -fsSL https://persistmemory.com/install.sh | less
#
# Environment:
#   PM_VERSION   install a specific npm version (default: latest)

set -eu

# Everything is inside this function, invoked on the very last line. A
# truncated download cannot execute half an install: it fails to parse.
main() {
  RED=''; BOLD=''; DIM=''; OFF=''
  if [ -t 1 ]; then
    RED=$(printf '\033[31m'); BOLD=$(printf '\033[1m')
    DIM=$(printf '\033[2m'); OFF=$(printf '\033[0m')
  fi

  step() { printf '%s==>%s %s\n' "$BOLD" "$OFF" "$1"; }
  note() { printf '%s%s%s\n' "$DIM" "$1" "$OFF"; }
  die()  { printf '%s error:%s %s\n' "$RED" "$OFF" "$1" >&2; exit 1; }

  step "Installing the PersistMemory CLI"

  # A supported platform, named rather than assumed.
  os=$(uname -s 2>/dev/null || echo unknown)
  case "$os" in
    Linux|Darwin) ;;
    MINGW*|MSYS*|CYGWIN*)
      die "on Windows, install with: npm install -g @persistmemory/cli" ;;
    *)
      die "unsupported platform '$os'. Install with: npm install -g @persistmemory/cli" ;;
  esac

  # Node, because the CLI is a Node program. Checked BEFORE anything is
  # downloaded, so the failure arrives before the work rather than after it.
  if ! command -v node >/dev/null 2>&1; then
    die "Node.js 20 or newer is required, and 'node' was not found on PATH.
       Install it from https://nodejs.org and run this again."
  fi

  node_major=$(node -p 'process.versions.node.split(".")[0]' 2>/dev/null || echo 0)
  if [ "$node_major" -lt 20 ] 2>/dev/null; then
    die "Node.js 20 or newer is required; found $(node -v)."
  fi

  if ! command -v npm >/dev/null 2>&1; then
    die "'npm' was not found on PATH. It ships with Node.js."
  fi

  # Read through printenv so an unset variable is not an error under 'set -u'
  # and no brace expansion is needed. See the note at the top of this file.
  wanted=$(printenv PM_VERSION 2>/dev/null || true)
  package="@persistmemory/cli"
  if [ -n "$wanted" ]; then
    package="@persistmemory/cli@$wanted"
  fi

  step "Fetching $package"

  # No sudo, deliberately. If the global prefix is not writable, npm says so
  # and the two safe ways forward are printed below.
  if ! npm install -g "$package" >/dev/null 2>&1; then
    printf '\n'
    note "npm could not install globally. That is usually a permissions"
    note "problem with npm's own prefix rather than anything to do with"
    note "this package. Two ways forward, neither needing sudo:"
    printf '\n'
    printf '  1. Point npm somewhere you own:\n'
    printf '       npm config set prefix ~/.local\n'
    printf '       export PATH="$HOME/.local/bin:$PATH"\n'
    printf '       curl -fsSL https://persistmemory.com/install.sh | sh\n'
    printf '\n'
    printf '  2. Skip installing and run it on demand:\n'
    printf '       npx @persistmemory/cli auth login\n'
    printf '\n'
    die "install failed"
  fi

  if ! command -v pm >/dev/null 2>&1; then
    printf '\n'
    note "Installed, but 'pm' is not on your PATH. Add npm's global bin"
    note "directory to it:"
    printf '\n'
    printf '       export PATH="$(npm prefix -g)/bin:$PATH"\n'
    printf '\n'
  fi

  step "Installed $(pm --version 2>/dev/null || echo "$package")"
  printf '\n'
  printf 'Next:\n'
  printf '  %spm auth login%s                      sign in with your browser\n' "$BOLD" "$OFF"
  printf '  %spm remember "we chose Postgres"%s    capture something\n' "$BOLD" "$OFF"
  printf '  %spm search "what did we choose"%s     ask for it back\n' "$BOLD" "$OFF"
  printf '\n'
  printf 'Docs: https://persistmemory.com/docs/cli\n'
}

main "$@"