# Minimal self-contained VPC with one public subnet — enough for a single public
# instance, and a clean base to extend (private subnets, RDS, ALB) when scaling up.

resource "aws_vpc" "this" {
  cidr_block           = "10.0.0.0/16"
  enable_dns_support   = true
  enable_dns_hostnames = true
  tags                 = merge(local.tags, { Name = "${var.project_name}-vpc" })
}

resource "aws_internet_gateway" "this" {
  vpc_id = aws_vpc.this.id
  tags   = merge(local.tags, { Name = "${var.project_name}-igw" })
}

resource "aws_subnet" "public" {
  vpc_id                  = aws_vpc.this.id
  cidr_block              = "10.0.1.0/24"
  availability_zone       = data.aws_availability_zones.available.names[0]
  map_public_ip_on_launch = true
  tags                    = merge(local.tags, { Name = "${var.project_name}-public" })
}

resource "aws_route_table" "public" {
  vpc_id = aws_vpc.this.id

  route {
    cidr_block = "0.0.0.0/0"
    gateway_id = aws_internet_gateway.this.id
  }

  tags = merge(local.tags, { Name = "${var.project_name}-public-rt" })
}

resource "aws_route_table_association" "public" {
  subnet_id      = aws_subnet.public.id
  route_table_id = aws_route_table.public.id
}