#!/bin/bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
BACKEND_DIR="$SCRIPT_DIR/backend"
FRONTEND_DIR="$SCRIPT_DIR/frontend"
LOG_DIR="$SCRIPT_DIR/logs"
PROJECT_ENV="$SCRIPT_DIR/.env"
FRONTEND_ENV_LOCAL="$FRONTEND_DIR/.env.local"
BACKEND_PYTHON="$BACKEND_DIR/.venv/Scripts/python.exe"
FRONTEND_VITE="$FRONTEND_DIR/node_modules/.bin/vite.cmd"
RUN_ID="$(date +%Y%m%d-%H%M%S)"
BACKEND_LOG="$LOG_DIR/backend-start-${RUN_ID}.log"
BACKEND_ERR_LOG="$LOG_DIR/backend-start-${RUN_ID}.err.log"
FRONTEND_LOG="$LOG_DIR/frontend-start-${RUN_ID}.log"
FRONTEND_ERR_LOG="$LOG_DIR/frontend-start-${RUN_ID}.err.log"
KILL_PORT=false

if [[ "${1:-}" == "--kill-port" ]]; then
  KILL_PORT=true
elif [[ $# -gt 0 ]]; then
  echo "[ERROR] Unsupported argument: $1"
  echo "[ERROR] Usage: bash start.sh [--kill-port]"
  exit 1
fi

mkdir -p "$LOG_DIR"

port_in_use() {
  "$BACKEND_PYTHON" - "$1" <<'PY'
import socket, sys
port = int(sys.argv[1])
with socket.socket() as sock:
    sock.settimeout(0.2)
    sys.exit(0 if sock.connect_ex(("127.0.0.1", port)) == 0 else 1)
PY
}

to_windows_path() {
  local path="$1"
  if [[ "$path" =~ ^/mnt/([a-zA-Z])/(.*)$ ]]; then
    printf '%s:/%s' "${BASH_REMATCH[1]^}" "${BASH_REMATCH[2]}"
  elif [[ "$path" =~ ^/([a-zA-Z])/(.*)$ ]]; then
    printf '%s:/%s' "${BASH_REMATCH[1]^}" "${BASH_REMATCH[2]}"
  else
    printf '%s' "$path"
  fi
}

kill_port_process() {
  local port="$1"
  local pids
  pids="$(powershell.exe -NoProfile -Command '& {
    Get-NetTCPConnection -LocalPort '"$1"' -State Listen -ErrorAction SilentlyContinue |
      Select-Object -ExpandProperty OwningProcess -Unique
  }' | tr -d '\r' || true)"

  if [[ -z "$pids" ]]; then
    return 0
  fi

  while IFS= read -r pid; do
    [[ -z "$pid" ]] && continue
    powershell.exe -NoProfile -Command "Stop-Process -Id $pid -Force -ErrorAction SilentlyContinue" >/dev/null 2>&1 || true
    cmd.exe /c "taskkill /PID $pid /F" >/dev/null 2>&1 || true
  done <<< "$pids"
}

kill_process_tree() {
  local pid="$1"
  [[ -z "$pid" ]] && return 0
  cmd.exe /c "taskkill /PID $pid /T /F" >/dev/null 2>&1 || true
}

cleanup() {
  local exit_code=$?
  trap - INT TERM EXIT
  if [[ -n "${FRONTEND_PID:-}" ]]; then
    kill_process_tree "$FRONTEND_PID"
  fi
  if [[ -n "${BACKEND_PID:-}" ]]; then
    kill_process_tree "$BACKEND_PID"
  fi
  if [[ -n "${BACKEND_PORT:-}" ]]; then
    kill_port_process "$BACKEND_PORT"
  fi
  exit "$exit_code"
}
trap cleanup INT TERM EXIT

echo "=========================================="
echo "  Jarvis - Quick Start"
echo "=========================================="
echo

if [[ ! -x "$BACKEND_PYTHON" ]]; then
  echo "[ERROR] backend/.venv/Scripts/python.exe was not found."
  echo "[ERROR] Create the backend virtual environment first."
  exit 1
fi

if [[ ! -f "$FRONTEND_VITE" ]]; then
  echo "[ERROR] frontend/node_modules/.bin/vite.cmd was not found."
  echo "[ERROR] Install frontend dependencies first."
  exit 1
fi

if ! command -v powershell.exe >/dev/null 2>&1; then
  echo "[ERROR] powershell.exe was not found."
  exit 1
fi

if [[ ! -f "$PROJECT_ENV" ]]; then
  echo "[INFO] .env was not found in the project root."
  echo "[INFO] Create it before first run."
  echo
fi

echo "[1/3] Check backend environment..."
echo "[OK] Backend virtual environment is available."

echo
echo "[2/3] Check frontend dependencies..."
if [[ ! -x "$FRONTEND_DIR/node_modules/.bin/vite" && ! -x "$FRONTEND_DIR/node_modules/.bin/vite.cmd" ]]; then
  echo "[ERROR] frontend dependencies are missing."
  echo "[ERROR] Run: cd frontend && npm install"
  exit 1
fi
echo "[OK] Frontend dependencies are available."

BACKEND_HOST="127.0.0.1"
BACKEND_PORT=""
if [[ -f "$PROJECT_ENV" ]]; then
  ENV_HOST="$(grep '^HOST=' "$PROJECT_ENV" | cut -d'=' -f2- | tr -d '\r' || true)"
  ENV_PORT="$(grep '^PORT=' "$PROJECT_ENV" | cut -d'=' -f2- | tr -d '\r' || true)"
  if [[ -n "$ENV_HOST" ]]; then BACKEND_HOST="$ENV_HOST"; fi
  if [[ -n "$ENV_PORT" ]]; then BACKEND_PORT="$ENV_PORT"; fi
fi

if [[ -z "$BACKEND_PORT" ]]; then
  echo "[ERROR] PORT was not found in .env."
  echo "[ERROR] Set PORT in the project root .env and run start.sh again."
  exit 1
fi

FRONTEND_API_URL="http://${BACKEND_HOST}:${BACKEND_PORT}"
printf 'VITE_API_URL=%s\n' "$FRONTEND_API_URL" > "$FRONTEND_ENV_LOCAL"

echo
echo "[3/3] Start services..."
if port_in_use "$BACKEND_PORT"; then
  if [[ "$KILL_PORT" == true ]]; then
    echo "[INFO] Port ${BACKEND_PORT} is in use. Killing existing process..."
    kill_port_process "$BACKEND_PORT"
    sleep 2
  fi
fi

if port_in_use "$BACKEND_PORT"; then
  echo "[ERROR] Port ${BACKEND_PORT} is already in use."
  echo "[ERROR] Stop the existing service first, then run start.sh again."
  exit 1
fi

BACKEND_WIN_DIR="$(to_windows_path "$BACKEND_DIR")"
BACKEND_WIN_LOG="$(to_windows_path "$BACKEND_LOG")"
BACKEND_WIN_ERR_LOG="$(to_windows_path "$BACKEND_ERR_LOG")"
BACKEND_WIN_PYTHON="$(to_windows_path "$BACKEND_PYTHON")"
BACKEND_PID="$(powershell.exe -NoProfile -Command "& {
  \$process = Start-Process -FilePath '$BACKEND_WIN_PYTHON' -ArgumentList '-m','uvicorn','app.main:app','--reload','--host','$BACKEND_HOST','--port','$BACKEND_PORT' -WorkingDirectory '$BACKEND_WIN_DIR' -RedirectStandardOutput '$BACKEND_WIN_LOG' -RedirectStandardError '$BACKEND_WIN_ERR_LOG' -PassThru
  \$process.Id
}" | tr -d '\r')"

echo "Waiting for backend..."
sleep 5

if ! port_in_use "$BACKEND_PORT"; then
  echo "[ERROR] Backend did not start successfully."
  echo "[ERROR] Check log: $BACKEND_LOG"
  exit 1
fi

echo "Starting frontend on port 5173..."
FRONTEND_WIN_DIR="$(to_windows_path "$FRONTEND_DIR")"
FRONTEND_WIN_LOG="$(to_windows_path "$FRONTEND_LOG")"
FRONTEND_WIN_ERR_LOG="$(to_windows_path "$FRONTEND_ERR_LOG")"
FRONTEND_WIN_VITE="$(to_windows_path "$FRONTEND_VITE")"
FRONTEND_PID="$(powershell.exe -NoProfile -Command "& {
  \$process = Start-Process -FilePath '$FRONTEND_WIN_VITE' -ArgumentList '--host','0.0.0.0' -WorkingDirectory '$FRONTEND_WIN_DIR' -RedirectStandardOutput '$FRONTEND_WIN_LOG' -RedirectStandardError '$FRONTEND_WIN_ERR_LOG' -PassThru
  \$process.Id
}" | tr -d '\r')"

echo
echo "=========================================="
echo "  Started"
echo
echo "  Backend: http://${BACKEND_HOST}:${BACKEND_PORT}"
echo "  Frontend: http://localhost:5173"
echo "  API docs: http://${BACKEND_HOST}:${BACKEND_PORT}/docs"
echo
echo "  Logs:"
echo "  - $BACKEND_LOG"
echo "  - $FRONTEND_LOG"
echo "=========================================="
echo
echo "Press Ctrl+C to stop both services."
echo

while true; do
  backend_alive="$(powershell.exe -NoProfile -Command "Get-Process -Id $BACKEND_PID -ErrorAction SilentlyContinue | Select-Object -ExpandProperty Id" | tr -d '\r')"
  frontend_alive="$(powershell.exe -NoProfile -Command "Get-Process -Id $FRONTEND_PID -ErrorAction SilentlyContinue | Select-Object -ExpandProperty Id" | tr -d '\r')"

  if [[ -z "$backend_alive" ]]; then
    echo "[ERROR] Backend process exited."
    echo "[ERROR] Check log: $BACKEND_LOG"
    exit 1
  fi

  if [[ -z "$frontend_alive" ]]; then
    echo "[ERROR] Frontend process exited."
    echo "[ERROR] Check log: $FRONTEND_LOG"
    exit 1
  fi

  sleep 2
done