#!/bin/bash

# Test replica-based build locking mechanism
# This script demonstrates how the build system uses replicas for atomic locking

set -e

NAMESPACE="apps--droneio--prd"
DEPLOYMENT="buildah-external"

echo "🧪 Testing Replica-Based Build Locking"
echo "======================================"

# Function to get current replicas
get_replicas() {
    kubectl get deployment $DEPLOYMENT -n $NAMESPACE -o jsonpath='{.spec.replicas}'
}

# Function to check if build can start
can_start_build() {
    local replicas=$(get_replicas)
    if [ "$replicas" = "0" ]; then
        echo "✅ Build can start (replicas=0)"
        return 0
    else
        echo "❌ Build already running (replicas=$replicas)"
        return 1
    fi
}

# Function to start build (scale up)
start_build() {
    echo "🔒 Acquiring build lock (scaling up)..."
    kubectl scale deployment $DEPLOYMENT --replicas=1 -n $NAMESPACE
    echo "⏳ Waiting for pod to be ready..."
    kubectl wait --for=condition=ready pod -l app=buildah-external -n $NAMESPACE --timeout=120s
    echo "✅ Build lock acquired!"
}

# Function to end build (scale down)
end_build() {
    echo "🔽 Releasing build lock (scaling down)..."
    kubectl scale deployment $DEPLOYMENT --replicas=0 -n $NAMESPACE
    echo "⏳ Waiting for pods to terminate..."
    kubectl wait --for=delete pod -l app=buildah-external -n $NAMESPACE --timeout=60s || echo "Pods may still be terminating"
    echo "✅ Build lock released!"
}

# Test sequence
echo "📊 Current deployment status:"
kubectl get deployment $DEPLOYMENT -n $NAMESPACE

echo ""
echo "🔍 Checking if build can start..."
if can_start_build; then
    echo ""
    echo "🚀 Starting test build..."
    start_build
    
    echo ""
    echo "📊 Deployment during build:"
    kubectl get deployment $DEPLOYMENT -n $NAMESPACE
    kubectl get pods -l app=buildah-external -n $NAMESPACE
    
    echo ""
    echo "🔍 Testing concurrent build attempt..."
    if can_start_build; then
        echo "🚨 ERROR: Concurrent build should be blocked!"
        exit 1
    else
        echo "✅ Concurrent build correctly blocked!"
    fi
    
    echo ""
    echo "🛑 Ending test build..."
    end_build
    
    echo ""
    echo "📊 Final deployment status:"
    kubectl get deployment $DEPLOYMENT -n $NAMESPACE
    
    echo ""
    echo "🔍 Verifying build can start again..."
    if can_start_build; then
        echo "✅ Build system ready for next build!"
    else
        echo "🚨 ERROR: Build system not properly reset!"
        exit 1
    fi
else
    echo ""
    echo "⚠️ Cannot test - build already running"
    echo "Use: kubectl scale deployment $DEPLOYMENT --replicas=0 -n $NAMESPACE"
fi

echo ""
echo "🎉 Replica-based locking test completed successfully!"
echo ""
echo "💡 Benefits:"
echo "   ✅ Atomic operations (no race conditions)"
echo "   ✅ No lock files to manage"
echo "   ✅ Kubernetes-native approach"
echo "   ✅ Resource efficient (only runs when needed)"
echo "   ✅ Automatic cleanup on failure"