provider "aws" {
  region = "ap-south-1"
}

# EC2 instance
resource "aws_instance" "ec2_t2-micro" {
  ami                         = "ami-0861f4e788f5069dd"                  # Amazon Linux
  instance_type               = "t2.micro"                               # Instance type
  key_name                    = "kshitij-personal-ed25519"               # SSH keys
  subnet_id                   = "subnet-0f2515644bbe8e603"               # VPC -> Subnet ID
  associate_public_ip_address = true                                     # Public IP for SSH
  vpc_security_group_ids      = [aws_security_group.ec2_ssh_security.id] # VPC security group

  tags = {
    Name = "Test-EC2" # Instance name
  }
}

# Security group (firewall) for allowing incoming SSH connections
resource "aws_security_group" "ec2_ssh_security" {
  name = "allow_ssh" # Firewall rule name

  ingress {
    # Ingress rules (incoming)
    from_port   = 22                     # Starting port range
    to_port     = 22                     # End port range
    protocol    = "tcp"                  # Allowed protocol
    cidr_blocks = ["${var.ssh_ingress}"] # Allowed IP ranges
  }
  egress {
    from_port   = 0             # Starting port range; 0 implies all ports
    to_port     = 0             # End port range; 0 implies all ports
    protocol    = -1            # Allowed protocol; -1 implies all protocols (in HCL)
    cidr_blocks = ["0.0.0.0/0"] # Allowed IP ranges
  }
  # For each protocol, new block; eg. egress { from... to... protocol = "icmp" cidr...}
}