#!/bin/bash

# ============================================================================
# POUNCE ZERO-DOWNTIME DEPLOY SCRIPT
# - Builds locally first (optional)
# - Syncs only changed files
# - Hot-reloads backend without full restart
# - Rebuilds frontend in background
# ============================================================================

set -e

# Colors
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
RED='\033[0;31m'
CYAN='\033[0;36m'
NC='\033[0m' # No Color

# Server config
SERVER_USER="user"
SERVER_HOST="10.42.0.73"
SERVER_PATH="/home/user/pounce"
SERVER_PASS="user"

# Parse flags
QUICK_MODE=false
BACKEND_ONLY=false
FRONTEND_ONLY=false

while [[ "$#" -gt 0 ]]; do
    case $1 in
        -q|--quick) QUICK_MODE=true ;;
        -b|--backend) BACKEND_ONLY=true ;;
        -f|--frontend) FRONTEND_ONLY=true ;;
        *) COMMIT_MSG="$1" ;;
    esac
    shift
done

echo -e "${BLUE}═══════════════════════════════════════════════════════════════${NC}"
echo -e "${BLUE}              POUNCE ZERO-DOWNTIME DEPLOY                      ${NC}"
echo -e "${BLUE}═══════════════════════════════════════════════════════════════${NC}"

if $QUICK_MODE; then
    echo -e "${CYAN}⚡ Quick mode: Skipping git, only syncing changes${NC}"
fi

if $BACKEND_ONLY; then
    echo -e "${CYAN}🔧 Backend only mode${NC}"
fi

if $FRONTEND_ONLY; then
    echo -e "${CYAN}🎨 Frontend only mode${NC}"
fi

# Step 1: Git (unless quick mode)
if ! $QUICK_MODE; then
    echo -e "\n${YELLOW}[1/4] Git operations...${NC}"
    
    # Check for changes
    if git diff --quiet && git diff --staged --quiet; then
        echo "  No changes to commit"
    else
        git add -A
        
        if [ -z "$COMMIT_MSG" ]; then
            COMMIT_MSG="Deploy: $(date '+%Y-%m-%d %H:%M')"
        fi
        
        git commit -m "$COMMIT_MSG" || true
        echo "  ✓ Committed: $COMMIT_MSG"
    fi
    
    git push origin main 2>/dev/null && echo "  ✓ Pushed to git.6bit.ch" || echo "  ⚠ Push failed or nothing to push"
else
    echo -e "\n${YELLOW}[1/4] Skipping git (quick mode)${NC}"
fi

# Step 2: Sync files (only changed)
echo -e "\n${YELLOW}[2/4] Syncing changed files...${NC}"

RSYNC_OPTS="-az --info=name1 --delete"

if ! $BACKEND_ONLY; then
    echo "  Frontend:"
    sshpass -p "$SERVER_PASS" rsync $RSYNC_OPTS \
        --exclude 'node_modules' \
        --exclude '.next' \
        --exclude '.git' \
        frontend/ $SERVER_USER@$SERVER_HOST:$SERVER_PATH/frontend/ 2>&1 | sed 's/^/    /'
fi

if ! $FRONTEND_ONLY; then
    echo "  Backend:"
    sshpass -p "$SERVER_PASS" rsync $RSYNC_OPTS \
        --exclude '__pycache__' \
        --exclude '.pytest_cache' \
        --exclude 'venv' \
        --exclude '.git' \
        --exclude '*.pyc' \
        --exclude '.env' \
        --exclude '*.db' \
        backend/ $SERVER_USER@$SERVER_HOST:$SERVER_PATH/backend/ 2>&1 | sed 's/^/    /'
fi

# Step 3: Reload backend (graceful, no restart)
if ! $FRONTEND_ONLY; then
    echo -e "\n${YELLOW}[3/4] Reloading backend (graceful)...${NC}"
    sshpass -p "$SERVER_PASS" ssh $SERVER_USER@$SERVER_HOST << 'BACKEND_EOF'
        # Signal uvicorn to reload (if running with --reload)
        # Otherwise, just check it's running
        BACKEND_PID=$(pgrep -f 'uvicorn app.main:app' | head -1)
        
        if [ -n "$BACKEND_PID" ]; then
            # Touch a file to trigger auto-reload if uvicorn has --reload
            touch ~/pounce/backend/app/main.py
            echo "  ✓ Backend reload triggered (PID: $BACKEND_PID)"
        else
            echo "  ⚠ Backend not running, starting..."
            cd ~/pounce/backend
            source ../venv/bin/activate
            nohup uvicorn app.main:app --host 0.0.0.0 --port 8000 > backend.log 2>&1 &
            sleep 2
            echo "  ✓ Backend started"
        fi
BACKEND_EOF
else
    echo -e "\n${YELLOW}[3/4] Skipping backend (frontend only)${NC}"
fi

# Step 4: Rebuild frontend (in background to minimize downtime)
if ! $BACKEND_ONLY; then
    echo -e "\n${YELLOW}[4/4] Rebuilding frontend...${NC}"
    sshpass -p "$SERVER_PASS" ssh $SERVER_USER@$SERVER_HOST << 'FRONTEND_EOF'
        cd ~/pounce/frontend
        
        # Build new version
        echo "  Building..."
        npm run build 2>&1 | grep -E '(✓|○|λ|Error|error)' | head -10 | sed 's/^/    /'
        
        BUILD_EXIT=$?
        
        if [ $BUILD_EXIT -eq 0 ]; then
            # Gracefully restart Next.js
            NEXT_PID=$(pgrep -f 'next start' | head -1)
            
            if [ -n "$NEXT_PID" ]; then
                echo "  Restarting Next.js (PID: $NEXT_PID)..."
                kill $NEXT_PID 2>/dev/null
                sleep 1
            fi
            
            # Start new instance
            nohup npm run start > frontend.log 2>&1 &
            sleep 2
            
            # Verify
            NEW_PID=$(pgrep -f 'next start' | head -1)
            if [ -n "$NEW_PID" ]; then
                echo "  ✓ Frontend running (PID: $NEW_PID)"
            else
                echo "  ⚠ Frontend may not have started correctly"
            fi
        else
            echo "  ✗ Build failed, keeping old version"
        fi
FRONTEND_EOF
else
    echo -e "\n${YELLOW}[4/4] Skipping frontend (backend only)${NC}"
fi

# Summary
echo -e "\n${GREEN}═══════════════════════════════════════════════════════════════${NC}"
echo -e "${GREEN}                    ✅ DEPLOY COMPLETE!                         ${NC}"
echo -e "${GREEN}═══════════════════════════════════════════════════════════════${NC}"
echo -e ""
echo -e "  Frontend: ${BLUE}https://pounce.ch${NC} / http://$SERVER_HOST:3000"
echo -e "  Backend:  ${BLUE}https://pounce.ch/api${NC} / http://$SERVER_HOST:8000"
echo -e ""
echo -e "${CYAN}Quick commands:${NC}"
echo -e "  ./deploy.sh -q          # Quick sync, no git"
echo -e "  ./deploy.sh -b          # Backend only"
echo -e "  ./deploy.sh -f          # Frontend only"
echo -e "  ./deploy.sh \"message\"   # Full deploy with commit message"