# Terraform AWS Infrastructure Template
# Generates a production-ready VPC with ECS Fargate, RDS, and supporting resources

## Usage
Replace all values in locals {} with your project specifics, then run:
```bash
terraform init && terraform plan && terraform apply
```

```hcl
terraform {
  required_version = ">= 1.5"
  required_providers {
    aws = { source = "hashicorp/aws", version = "~> 5.0" }
  }
  backend "s3" {
    bucket         = "your-terraform-state-bucket"
    key            = "infrastructure/terraform.tfstate"
    region         = "eu-west-1"
    dynamodb_table = "terraform-locks"
    encrypt        = true
  }
}

locals {
  project     = "myproject"
  environment = "production"
  region      = "eu-west-1"
  domain      = "myproject.com"
  
  tags = {
    Project     = local.project
    Environment = local.environment
    ManagedBy   = "terraform"
  }
}

# VPC with public + private subnets across 3 AZs
module "vpc" {
  source  = "terraform-aws-modules/vpc/aws"
  version = "~> 5.0"
  
  name = "${local.project}-${local.environment}"
  cidr = "10.0.0.0/16"
  
  azs             = ["${local.region}a", "${local.region}b", "${local.region}c"]
  private_subnets = ["10.0.1.0/24", "10.0.2.0/24", "10.0.3.0/24"]
  public_subnets  = ["10.0.101.0/24", "10.0.102.0/24", "10.0.103.0/24"]
  
  enable_nat_gateway = true
  single_nat_gateway = false  # HA: one per AZ
  
  tags = local.tags
}

# ECS Fargate Cluster
resource "aws_ecs_cluster" "main" {
  name = "${local.project}-${local.environment}"
  setting {
    name  = "containerInsights"
    value = "enabled"
  }
  tags = local.tags
}

# RDS PostgreSQL
module "db" {
  source  = "terraform-aws-modules/rds/aws"
  version = "~> 6.0"
  
  identifier = "${local.project}-${local.environment}"
  engine     = "postgres"
  engine_version = "16"
  
  instance_class    = "db.t4g.medium"
  allocated_storage = 100
  storage_encrypted = true
  
  vpc_security_group_ids = [module.security_group.security_group_id]
  db_subnet_group_name   = module.vpc.database_subnet_group
  
  backup_retention_period = 30
  deletion_protection     = true
  
  tags = local.tags
}
```

Customize: instance sizes, regions, services, monitoring thresholds.