Parameterize Terraform remote state (AWS)

remote_state.tf

data "aws_caller_identity" "current" {}

resource "aws_s3_bucket" "terraform_state" {
  bucket = "${data.aws_caller_identity.current.account_id}-tfstate"
  versioning {
    enabled = true
  }
  policy = <<POLICY
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "s3:ListBucket",
            "Principal": {
                "AWS": [
                    "arn:aws:iam::${data.aws_caller_identity.current.account_id}:user/svc-jenkins",
                    "arn:aws:iam::${data.aws_caller_identity.current.account_id}:user/amotta"
                ]
            },
            "Resource": "arn:aws:s3:::${data.aws_caller_identity.current.account_id}-tfstate"
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetObject",
                "s3:PutObject"
            ],
            "Principal": {
                "AWS": [
                    "arn:aws:iam::${data.aws_caller_identity.current.account_id}:user/svc-jenkins",
                    "arn:aws:iam::${data.aws_caller_identity.current.account_id}:user/amotta"
                ]
            },
            "Resource": "arn:aws:s3:::${data.aws_caller_identity.current.account_id}-tfstate/*"
        }
    ]
}
POLICY
}

terraform {
  backend "s3" {}
  depends_on = ["aws_s3_bucket.terraform_state"]
}

state_overrides.sh

terraform init -backend-config="bucket=${ACCOUNT}-tfstate" -backend-config="key=${TF_VAR_stack_name}/terraform.tfstate" -backend-config="region=us-west-2