#!/bin/bash
# Start both backend and frontend services for SBA gameplay testing
# Enhanced with pre-flight checks, health monitoring, and version logging

set -e

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
LOG_DIR="$SCRIPT_DIR/logs"

# Default configuration
BACKEND_PORT=8000
FRONTEND_PORT=3000
BACKEND_HOST="0.0.0.0"
FRONTEND_HOST="0.0.0.0"
HEALTH_CHECK_HOST="localhost"  # For curl health checks

# Environment mode (affects .env file used)
ENV_MODE="dev"  # dev, prod, or custom

# Parse arguments
FORCE_START=false
FRONTEND_TYPE="sba"  # Default to SBA frontend

while [[ $# -gt 0 ]]; do
    case $1 in
        --force|-f)
            FORCE_START=true
            shift
            ;;
        --frontend)
            FRONTEND_TYPE="$2"
            shift 2
            ;;
        --pd)
            FRONTEND_TYPE="pd"
            shift
            ;;
        --dev)
            ENV_MODE="dev"
            shift
            ;;
        --prod)
            ENV_MODE="prod"
            shift
            ;;
        --backend-port)
            BACKEND_PORT="$2"
            shift 2
            ;;
        --frontend-port)
            FRONTEND_PORT="$2"
            shift 2
            ;;
        --help|-h)
            echo "Usage: $0 [OPTIONS]"
            echo ""
            echo "Options:"
            echo "  --force, -f       Force start (stop existing services first)"
            echo "  --frontend TYPE   Start specific frontend (sba or pd)"
            echo "  --pd              Shortcut for --frontend pd"
            echo "  --dev             Development mode - use localhost URLs (default)"
            echo "  --prod            Production mode - use .env production URLs"
            echo "  --backend-port N  Override backend port (default: 8000)"
            echo "  --frontend-port N Override frontend port (default: 3000)"
            echo "  --help, -h        Show this help message"
            echo ""
            echo "Environment Modes:"
            echo "  --dev   Sets NUXT_PUBLIC_API_URL=http://localhost:8000"
            echo "          Sets NUXT_PUBLIC_WS_URL=http://localhost:8000"
            echo ""
            echo "  --prod  Uses URLs from frontend-{sba,pd}/.env file"
            echo "          (e.g., https://gameplay-demo.manticorum.com)"
            exit 0
            ;;
        *)
            echo "Unknown option: $1"
            exit 1
            ;;
    esac
done

# Validate frontend type
if [[ "$FRONTEND_TYPE" != "sba" && "$FRONTEND_TYPE" != "pd" ]]; then
    echo "❌ Invalid frontend type: $FRONTEND_TYPE (must be 'sba' or 'pd')"
    exit 1
fi

FRONTEND_DIR="$SCRIPT_DIR/frontend-$FRONTEND_TYPE"

# Create logs directory if it doesn't exist
mkdir -p "$LOG_DIR"

echo "========================================"
echo "🚀 Starting SBA Gameplay Services"
echo "========================================"
echo ""

# ============================================
# PRE-FLIGHT CHECKS
# ============================================
echo "🔍 Pre-flight checks..."

# Check dependencies
check_dependency() {
    if ! command -v "$1" &> /dev/null; then
        echo "❌ Required tool not found: $1"
        echo "   Please install $1 before running this script."
        exit 1
    fi
}

check_dependency "uv"
check_dependency "npm"
check_dependency "curl"
echo "   ✓ Dependencies available (uv, npm, curl)"

# Check if frontend directory exists
if [ ! -d "$FRONTEND_DIR" ]; then
    echo "❌ Frontend directory not found: $FRONTEND_DIR"
    exit 1
fi
echo "   ✓ Frontend directory exists: frontend-$FRONTEND_TYPE"

# Check if already running
ALREADY_RUNNING=false

if [ -f "$LOG_DIR/backend.pid" ]; then
    EXISTING_PID=$(cat "$LOG_DIR/backend.pid")
    if ps -p "$EXISTING_PID" > /dev/null 2>&1; then
        ALREADY_RUNNING=true
        echo "   ⚠️  Backend already running (PID: $EXISTING_PID)"
    fi
fi

if [ -f "$LOG_DIR/frontend.pid" ]; then
    EXISTING_PID=$(cat "$LOG_DIR/frontend.pid")
    if ps -p "$EXISTING_PID" > /dev/null 2>&1; then
        ALREADY_RUNNING=true
        echo "   ⚠️  Frontend already running (PID: $EXISTING_PID)"
    fi
fi

if [ "$ALREADY_RUNNING" = true ]; then
    if [ "$FORCE_START" = true ]; then
        echo "   → Force flag set, stopping existing services..."
        "$SCRIPT_DIR/stop-services.sh"
        echo ""
    else
        echo ""
        echo "❌ Services already running. Use --force to restart or run ./stop-services.sh first."
        exit 1
    fi
fi

# Check port availability
check_port() {
    local port=$1
    local name=$2
    if lsof -ti :"$port" > /dev/null 2>&1; then
        echo "   ⚠️  Port $port is in use ($name)"
        if [ "$FORCE_START" = true ]; then
            echo "   → Force flag set, killing processes on port $port..."
            lsof -ti :"$port" | xargs kill -9 2>/dev/null || true
            sleep 1
        else
            echo ""
            echo "❌ Port $port is in use. Use --force to kill existing processes."
            exit 1
        fi
    fi
}

check_port $BACKEND_PORT "backend"
check_port $FRONTEND_PORT "frontend"
echo "   ✓ Ports $BACKEND_PORT and $FRONTEND_PORT available"

echo ""

# ============================================
# VERSION LOGGING (helps debug deployment issues)
# ============================================
echo "📌 Version Info:"
GIT_COMMIT=$(git -C "$SCRIPT_DIR" rev-parse --short HEAD 2>/dev/null || echo "unknown")
GIT_BRANCH=$(git -C "$SCRIPT_DIR" rev-parse --abbrev-ref HEAD 2>/dev/null || echo "unknown")
GIT_DIRTY=$(git -C "$SCRIPT_DIR" diff --quiet 2>/dev/null && echo "" || echo " (dirty)")
TIMESTAMP=$(date -Iseconds)

echo "   Branch: $GIT_BRANCH"
echo "   Commit: $GIT_COMMIT$GIT_DIRTY"
echo "   Started: $TIMESTAMP"

# Log to file for debugging
cat > "$LOG_DIR/startup.log" << EOF
========================================
Service Startup Log
========================================
Timestamp: $TIMESTAMP
Git Branch: $GIT_BRANCH
Git Commit: $GIT_COMMIT$GIT_DIRTY
Environment: $ENV_MODE
Frontend: $FRONTEND_TYPE
Backend Port: $BACKEND_PORT
Frontend Port: $FRONTEND_PORT
========================================
EOF

echo ""

# ============================================
# START BACKEND
# ============================================
echo "📡 Starting Backend (FastAPI + Socket.io)..."
cd "$SCRIPT_DIR/backend"
uv run python -m app.main > "$LOG_DIR/backend.log" 2>&1 &
BACKEND_PID=$!
echo "$BACKEND_PID" > "$LOG_DIR/backend.pid"
echo "   PID: $BACKEND_PID"
echo "   Log: $LOG_DIR/backend.log"

# Health check with timeout
echo "   Waiting for backend to be ready..."
HEALTH_TIMEOUT=30
HEALTH_COUNT=0
BACKEND_READY=false

while [ $HEALTH_COUNT -lt $HEALTH_TIMEOUT ]; do
    # Check if process is still running
    if ! ps -p $BACKEND_PID > /dev/null 2>&1; then
        echo ""
        echo "❌ Backend process died during startup!"
        echo "   Check logs: tail -50 $LOG_DIR/backend.log"
        tail -20 "$LOG_DIR/backend.log" 2>/dev/null || true
        exit 1
    fi

    # Check health endpoint
    if curl -s http://$HEALTH_CHECK_HOST:$BACKEND_PORT/health > /dev/null 2>&1; then
        BACKEND_READY=true
        break
    fi

    # Also accept root endpoint as fallback
    if curl -s http://$HEALTH_CHECK_HOST:$BACKEND_PORT/ > /dev/null 2>&1; then
        BACKEND_READY=true
        break
    fi

    sleep 1
    HEALTH_COUNT=$((HEALTH_COUNT + 1))
    printf "."
done

echo ""

if [ "$BACKEND_READY" = true ]; then
    echo "   ✓ Backend ready (${HEALTH_COUNT}s)"
    echo "   URL: http://localhost:$BACKEND_PORT"
else
    echo "   ⚠️  Backend health check timed out after ${HEALTH_TIMEOUT}s"
    echo "   Backend may still be starting. Check logs if issues occur."
fi

echo ""

# ============================================
# START FRONTEND
# ============================================
echo "🎨 Starting Frontend (Nuxt 3 - $FRONTEND_TYPE)..."
cd "$FRONTEND_DIR"

# Set environment variables based on mode
if [ "$ENV_MODE" = "dev" ]; then
    echo "   Mode: Development (localhost)"
    export NUXT_PUBLIC_API_URL="http://localhost:$BACKEND_PORT"
    export NUXT_PUBLIC_WS_URL="http://localhost:$BACKEND_PORT"
    export NUXT_PUBLIC_DISCORD_REDIRECT_URI="http://localhost:$FRONTEND_PORT/auth/callback"
elif [ "$ENV_MODE" = "prod" ]; then
    echo "   Mode: Production (using .env file)"
    # Load .env file if it exists (Nuxt will use these)
    if [ -f ".env" ]; then
        # Show what URLs will be used
        API_URL=$(grep "^NUXT_PUBLIC_API_URL=" .env 2>/dev/null | cut -d= -f2 || echo "not set")
        echo "   API URL: $API_URL"
    else
        echo "   ⚠️  No .env file found - using Nuxt defaults"
    fi
fi

npm run dev > "$LOG_DIR/frontend.log" 2>&1 &
FRONTEND_PID=$!
echo "$FRONTEND_PID" > "$LOG_DIR/frontend.pid"
echo "   PID: $FRONTEND_PID"
echo "   Log: $LOG_DIR/frontend.log"

# Wait for frontend to be ready
echo "   Waiting for frontend to be ready..."
FRONTEND_TIMEOUT=60
FRONTEND_COUNT=0
FRONTEND_READY=false

while [ $FRONTEND_COUNT -lt $FRONTEND_TIMEOUT ]; do
    # Check if process is still running
    if ! ps -p $FRONTEND_PID > /dev/null 2>&1; then
        echo ""
        echo "❌ Frontend process died during startup!"
        echo "   Check logs: tail -50 $LOG_DIR/frontend.log"
        tail -20 "$LOG_DIR/frontend.log" 2>/dev/null || true
        exit 1
    fi

    # Check if frontend is responding
    if curl -s http://$HEALTH_CHECK_HOST:$FRONTEND_PORT > /dev/null 2>&1; then
        FRONTEND_READY=true
        break
    fi

    sleep 1
    FRONTEND_COUNT=$((FRONTEND_COUNT + 1))
    printf "."
done

echo ""

if [ "$FRONTEND_READY" = true ]; then
    echo "   ✓ Frontend ready (${FRONTEND_COUNT}s)"
    echo "   URL: http://localhost:$FRONTEND_PORT"
else
    echo "   ⚠️  Frontend health check timed out after ${FRONTEND_TIMEOUT}s"
    echo "   Frontend may still be compiling. Check logs if issues occur."
fi

echo ""

# ============================================
# SUMMARY
# ============================================
echo "========================================"
echo "✅ Services Started Successfully!"
echo "========================================"
echo ""
echo "📊 Service Status:"
echo "   Backend:  http://localhost:$BACKEND_PORT (PID: $BACKEND_PID)"
echo "   Frontend: http://localhost:$FRONTEND_PORT (PID: $FRONTEND_PID)"
echo ""

# Show API URL based on mode
if [ "$ENV_MODE" = "dev" ]; then
    echo "🔗 API Configuration (dev mode):"
    echo "   API URL: http://localhost:$BACKEND_PORT"
    echo "   WS URL:  http://localhost:$BACKEND_PORT"
elif [ "$ENV_MODE" = "prod" ]; then
    echo "🔗 API Configuration (prod mode):"
    if [ -f "$FRONTEND_DIR/.env" ]; then
        grep "^NUXT_PUBLIC_API_URL=" "$FRONTEND_DIR/.env" 2>/dev/null | sed 's/^/   /' || true
        grep "^NUXT_PUBLIC_WS_URL=" "$FRONTEND_DIR/.env" 2>/dev/null | sed 's/^/   /' || true
    fi
fi
echo ""

echo "📋 Quick Commands:"
echo "   View logs:    tail -f $LOG_DIR/backend.log"
echo "                 tail -f $LOG_DIR/frontend.log"
echo "   Check status: ./status-services.sh"
echo "   Stop:         ./stop-services.sh"
echo "   Restart:      ./stop-services.sh && ./start-services.sh"
echo ""
echo "📌 Running: $GIT_BRANCH @ $GIT_COMMIT$GIT_DIRTY ($ENV_MODE mode)"
echo ""