#!/bin/bash
# AWS VPC and Network provisioning script
# Generated by provisioning {{ provisioning_version }} at {{ now }}
# Reference: AWS EC2 VPC - https://docs.aws.amazon.com/vpc/latest/userguide/what-is-amazon-vpc.html

set -e
{% if debug and debug == "yes" %}set -x{% endif %}

# Validate AWS CLI is installed
if ! command -v aws &> /dev/null; then
    echo "ERROR: AWS CLI is not installed"
    exit 1
fi

# Validate required environment
if [ -z "$AWS_REGION" ]; then
    echo "ERROR: AWS_REGION environment variable not set"
    exit 1
fi

# VPC Configuration
VPC_NAME="{{ vpc.name | default('provisioning-vpc') }}"
VPC_CIDR="{{ vpc.cidr_block | default('10.0.0.0/16') }}"
VPC_DESCRIPTION="{{ vpc.description | default('VPC created by provisioning') }}"

# Validate required fields
if [ -z "$VPC_NAME" ]; then
    echo "ERROR: VPC name is required"
    exit 1
fi

echo "Creating VPC: $VPC_NAME with CIDR: $VPC_CIDR..."

# Create VPC
VPC_ID=$(aws ec2 create-vpc \
    --cidr-block "$VPC_CIDR" \
    --tag-specifications "ResourceType=vpc,Tags=[{Key=Name,Value=$VPC_NAME}]" \
    --region "$AWS_REGION" \
    --query 'Vpc.VpcId' \
    --output text)

if [ -z "$VPC_ID" ]; then
    echo "ERROR: Failed to create VPC"
    exit 1
fi

echo "✓ VPC created successfully"
echo "  VPC ID: $VPC_ID"
echo "  CIDR: $VPC_CIDR"

# Enable DNS support
aws ec2 modify-vpc-attribute \
    --vpc-id "$VPC_ID" \
    --enable-dns-support \
    --region "$AWS_REGION"

aws ec2 modify-vpc-attribute \
    --vpc-id "$VPC_ID" \
    --enable-dns-hostnames \
    --region "$AWS_REGION"

echo "✓ DNS support enabled for VPC"

{% if vpc.subnets %}
# Create Subnets
echo ""
echo "Creating subnets..."
{% for subnet in vpc.subnets %}

SUBNET_NAME="{{ subnet.name | default('subnet-' + loop.index0 | string) }}"
SUBNET_CIDR="{{ subnet.cidr_block | default('10.0.' + loop.index0 | string + '.0/24') }}"
SUBNET_AZ="{{ subnet.availability_zone | default('') }}"

echo "Creating subnet: $SUBNET_NAME with CIDR: $SUBNET_CIDR..."

# Build aws ec2 create-subnet command
CREATE_SUBNET_CMD="aws ec2 create-subnet \
    --vpc-id $VPC_ID \
    --cidr-block $SUBNET_CIDR"

{% if subnet.availability_zone %}
CREATE_SUBNET_CMD="$CREATE_SUBNET_CMD --availability-zone $SUBNET_AZ"
{% endif %}

CREATE_SUBNET_CMD="$CREATE_SUBNET_CMD \
    --tag-specifications 'ResourceType=subnet,Tags=[{Key=Name,Value=$SUBNET_NAME}]' \
    --region $AWS_REGION \
    --query 'Subnet.SubnetId' \
    --output text"

SUBNET_ID=$(eval "$CREATE_SUBNET_CMD")

if [ -z "$SUBNET_ID" ]; then
    echo "ERROR: Failed to create subnet $SUBNET_NAME"
    exit 1
fi

echo "  ✓ Subnet created: $SUBNET_ID"
echo "    CIDR: $SUBNET_CIDR"

{% if subnet.map_public_ip_on_launch %}
# Enable public IP assignment
aws ec2 modify-subnet-attribute \
    --subnet-id "$SUBNET_ID" \
    --map-public-ip-on-launch \
    --region "$AWS_REGION"

echo "  ✓ Public IP assignment enabled"
{% endif %}

{% endfor %}
{% endif %}

{% if vpc.enable_nat_gateway %}
# Create Internet Gateway
echo ""
echo "Creating Internet Gateway..."

IGW_NAME="{{ vpc.name }}-igw"
IGW_ID=$(aws ec2 create-internet-gateway \
    --tag-specifications "ResourceType=internet-gateway,Tags=[{Key=Name,Value=$IGW_NAME}]" \
    --region "$AWS_REGION" \
    --query 'InternetGateway.InternetGatewayId' \
    --output text)

if [ -z "$IGW_ID" ]; then
    echo "ERROR: Failed to create Internet Gateway"
    exit 1
fi

# Attach IGW to VPC
aws ec2 attach-internet-gateway \
    --internet-gateway-id "$IGW_ID" \
    --vpc-id "$VPC_ID" \
    --region "$AWS_REGION"

echo "✓ Internet Gateway created and attached"
echo "  IGW ID: $IGW_ID"

{% if vpc.create_nat_instance %}
# Create NAT Gateway (requires Elastic IP)
echo ""
echo "Creating NAT Gateway..."

# Allocate Elastic IP
EIP_ID=$(aws ec2 allocate-address \
    --domain vpc \
    --region "$AWS_REGION" \
    --query 'AllocationId' \
    --output text)

if [ -z "$EIP_ID" ]; then
    echo "ERROR: Failed to allocate Elastic IP"
    exit 1
fi

echo "  ✓ Elastic IP allocated: $EIP_ID"

# Create NAT Gateway in first public subnet
{% if vpc.subnets %}
FIRST_SUBNET_ID=$(aws ec2 describe-subnets \
    --filters "Name=vpc-id,Values=$VPC_ID" \
    --region "$AWS_REGION" \
    --query 'Subnets[0].SubnetId' \
    --output text)

NAT_GW_ID=$(aws ec2 create-nat-gateway \
    --subnet-id "$FIRST_SUBNET_ID" \
    --allocation-id "$EIP_ID" \
    --tag-specifications "ResourceType=natgateway,Tags=[{Key=Name,Value={{ vpc.name }}-nat}]" \
    --region "$AWS_REGION" \
    --query 'NatGateway.NatGatewayId' \
    --output text)

if [ -z "$NAT_GW_ID" ]; then
    echo "ERROR: Failed to create NAT Gateway"
    exit 1
fi

echo "  ✓ NAT Gateway created: $NAT_GW_ID"

# Wait for NAT Gateway to be available
echo "  Waiting for NAT Gateway to become available..."
aws ec2 wait nat-gateway-available \
    --nat-gateway-ids "$NAT_GW_ID" \
    --region "$AWS_REGION"

echo "  ✓ NAT Gateway is available"
{% endif %}
{% endif %}
{% endif %}

{% if vpc.tags %}
# Apply additional tags
echo ""
echo "Applying tags to VPC..."
{% for key, value in vpc.tags.items() %}
aws ec2 create-tags \
    --resources "$VPC_ID" \
    --tags "Key={{ key }},Value={{ value }}" \
    --region "$AWS_REGION"
{% endfor %}
echo "✓ Tags applied"
{% endif %}

# Output VPC details
echo ""
echo "VPC Configuration Summary:"
echo "  VPC ID: $VPC_ID"
echo "  VPC Name: $VPC_NAME"
echo "  CIDR Block: $VPC_CIDR"
echo "  Region: $AWS_REGION"

aws ec2 describe-vpcs \
    --vpc-ids "$VPC_ID" \
    --region "$AWS_REGION" \
    --query 'Vpcs[0].[VpcId,CidrBlock,State]' \
    --output table

exit 0