# Create VPC
resource "aws_vpc" "example" {
  cidr_block       = "10.0.0.0/16"
  enable_dns_hostnames = true

  tags = {
    Name = "example-vpc"
  }
}

# Create public subnets
resource "aws_subnet" "public" {
  count             = 2
  vpc_id            = aws_vpc.example.id
  cidr_block        = "10.0.${count.index}.0/24"
  availability_zone = "us-west-2a"
  map_public_ip_on_launch = true

  tags = {
    Name = "example-public-${count.index+1}"
  }
}

# Create private subnets
resource "aws_subnet" "private" {
  count             = 2
  vpc_id            = aws_vpc.example.id
  cidr_block        = "10.0.${count.index+2}.0/24"
  availability_zone = "us-west-2a"
  map_public_ip_on_launch = false

  tags = {
    Name = "example-private-${count.index+1}"
  }
}

# Create security group for public subnets
resource "aws_security_group" "public" {
  name        = "public"
  description = "Allow HTTP and HTTPS traffic"
  vpc_id      = aws_vpc.example.id

  ingress {
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  ingress {
    from_port   = 443
    to_port     = 443
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

# Create security group for private subnets
resource "aws_security_group" "private" {
  name        = "private"
  description = "Allow all traffic"
  vpc_id      = aws_vpc.example.id

  ingress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

# Create Application Load Balancer
resource "aws_alb" "example" {
  name            = "example-alb"
  internal        = false
  security_groups = [aws_security_group.alb.id]
  subnets         = [aws_subnet.public.id]

  tags = {
    Name = "example-alb"
  }
}

# Create target group
resource "aws_alb_target_group" "example" {
  name     = "example-target-group"
  port     = 80
  protocol = "HTTP"
  vpc_id   = aws_vpc.example.id
}
resource "aws_alb_target_group_attachment" "example" {
  target_group_arn = aws_alb_target_group.example.arn
  target_id        = aws_instance.example.id
  port             = 80
}

resource "aws_alb_listener" "example" {
  load_balancer_arn = aws_alb.example.arn
  port              = "80"
  protocol          = "HTTP"

  default_action {
    type             = "forward"
    target_group_arn = aws_alb_target_group.example.arn
  }
}