#!/usr/bin/env bash
# ============================================================================
# SHARP-ER - check that this machine can run the project
# ----------------------------------------------------------------------------
#   ./scripts/check-prereqs.sh            check both setup paths, report
#   ./scripts/check-prereqs.sh manual     only the tools PATH A needs
#   ./scripts/check-prereqs.sh docker     only the tools PATH B needs
#
# Exits non-zero when a tool the chosen path REQUIRES is missing or too old, so
# it can be used as a gate in CI or in an onboarding script. Read-only: it
# starts nothing, installs nothing and writes nothing.
# ============================================================================
set -uo pipefail

MODE="${1:-all}"
case "$MODE" in
  all|manual|docker) ;;
  -h|--help)
    printf 'usage: check-prereqs.sh [all|manual|docker]\n'
    exit 0 ;;
  *)
    printf 'unknown mode: %s (use all, manual or docker)\n' "$MODE" >&2
    exit 2 ;;
esac

# Versions this repository is developed against.
NODE_MIN="22.22.0"     # React Router 8 requires >= 22.22.0
PNPM_MAJOR="9"         # packageManager: pnpm@9.12.3
PG_MAJOR="16"

if [ -t 1 ] && [ -z "${NO_COLOR:-}" ]; then
  C_OK=$'\033[32m'; C_WARN=$'\033[33m'; C_ERR=$'\033[31m'; C_DIM=$'\033[2m'; C_OFF=$'\033[0m'
else
  C_OK=""; C_WARN=""; C_ERR=""; C_DIM=""; C_OFF=""
fi

FAILED=0
pass() { printf '%s  ok  %s %-22s %s\n' "$C_OK"   "$C_OFF" "$1" "${2:-}"; }
warn() { printf '%s warn %s %-22s %s\n' "$C_WARN" "$C_OFF" "$1" "${2:-}"; }
fail() { printf '%s fail %s %-22s %s\n' "$C_ERR"  "$C_OFF" "$1" "${2:-}"; FAILED=1; }
note() { printf '%s      %s %-22s %s\n' "$C_DIM"  "$C_OFF" "" "$1"; }

# true when $1 >= $2, comparing dotted versions numerically.
version_ge() {
  [ "$1" = "$2" ] && return 0
  [ "$(printf '%s\n%s\n' "$1" "$2" | sort -V | head -n1)" = "$2" ]
}

# Strip a leading v and anything after the numeric part: "v22.23.2" -> 22.23.2
clean_version() { printf '%s' "$1" | sed -E 's/^v//; s/[^0-9.].*$//'; }

check_node() {
  if ! command -v node >/dev/null 2>&1; then
    fail "node" "not installed - need >= $NODE_MIN"
    note "nvm install \$(cat .nvmrc)   # .nvmrc pins the version this repo uses"
    return
  fi
  local version; version="$(clean_version "$(node --version)")"
  if version_ge "$version" "$NODE_MIN"; then
    pass "node $version" ">= $NODE_MIN"
  else
    fail "node $version" "too old - React Router 8 requires >= $NODE_MIN"
    note "nvm install \$(cat .nvmrc) && nvm use"
  fi
}

check_pnpm() {
  if ! command -v pnpm >/dev/null 2>&1; then
    fail "pnpm" "not installed - need $PNPM_MAJOR.x"
    note "corepack enable && corepack prepare pnpm@9.12.3 --activate"
    return
  fi
  local version major; version="$(clean_version "$(pnpm --version)")"; major="${version%%.*}"
  if [ "$major" = "$PNPM_MAJOR" ]; then
    pass "pnpm $version" "major $PNPM_MAJOR"
  else
    warn "pnpm $version" "repo pins pnpm@9.12.3 - the lockfile may be rewritten"
  fi
}

check_postgres_client() {
  if ! command -v psql >/dev/null 2>&1; then
    fail "psql" "not installed - need the PostgreSQL $PG_MAJOR client"
    note "sudo apt install postgresql-$PG_MAJOR postgresql-client-$PG_MAJOR"
    return
  fi
  local version major
  version="$(clean_version "$(psql --version | awk '{print $3}')")"
  major="${version%%.*}"
  if [ "$major" = "$PG_MAJOR" ]; then
    pass "psql $version" "major $PG_MAJOR"
  else
    warn "psql $version" "developed against PostgreSQL $PG_MAJOR"
  fi
}

check_postgres_server() {
  command -v pg_isready >/dev/null 2>&1 || { note "pg_isready not found - skipped the server check"; return; }
  local host="${DATABASE_HOST:-127.0.0.1}" port="${DATABASE_PORT:-5432}"
  if pg_isready --host "$host" --port "$port" --timeout 3 >/dev/null 2>&1; then
    pass "postgres server" "answering on $host:$port"
  else
    warn "postgres server" "nothing on $host:$port - start it before ./scripts/setup-db.sh"
  fi
}

check_docker() {
  if ! command -v docker >/dev/null 2>&1; then
    fail "docker" "not installed"
    note "https://docs.docker.com/engine/install/"
    return
  fi
  pass "docker" "$(docker --version 2>/dev/null | sed 's/,.*//')"
  if docker compose version >/dev/null 2>&1; then
    pass "docker compose" "$(docker compose version --short 2>/dev/null)"
  else
    fail "docker compose" "v2 plugin missing (the old docker-compose binary is not supported)"
  fi
  if ! docker info >/dev/null 2>&1; then
    warn "docker daemon" "not reachable - start Docker, or add your user to the docker group"
  fi
}

check_env_files() {
  local root; root="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)"
  [ -f "$root/.env" ] && pass ".env" "present" || warn ".env" "missing - cp .env.example .env"
  if [ "$MODE" != "docker" ]; then
    [ -f "$root/apps/cms/.env" ] \
      && pass "apps/cms/.env" "present" \
      || warn "apps/cms/.env" "missing - cp apps/cms/.env.example apps/cms/.env"
  fi
}

printf '\nSHARP-ER prerequisites (%s)\n\n' "$MODE"

if [ "$MODE" = "manual" ] || [ "$MODE" = "all" ]; then
  printf '%sPATH A - manual%s\n' "$C_DIM" "$C_OFF"
  check_node
  check_pnpm
  check_postgres_client
  check_postgres_server
  printf '\n'
fi

if [ "$MODE" = "docker" ] || [ "$MODE" = "all" ]; then
  printf '%sPATH B - docker%s\n' "$C_DIM" "$C_OFF"
  check_docker
  printf '\n'
fi

printf '%sEnvironment files%s\n' "$C_DIM" "$C_OFF"
check_env_files
printf '\n'

if [ "$FAILED" -ne 0 ]; then
  printf '%sSomething required is missing - see the lines marked fail.%s\n\n' "$C_ERR" "$C_OFF"
  exit 1
fi

printf '%sReady. Next: README.md, "PATH A" or "PATH B".%s\n\n' "$C_OK" "$C_OFF"