# 🤖 The fleet-backup bucket: Litestream on the router box streams every
# instance DB (plus home/push/cloud/registry) here, one prefix per database.
# Versioning is the ransomware posture — an overwrite or delete with the
# box's credentials leaves noncurrent versions recoverable for 14 days, and
# the box's IAM user (below) cannot touch versioning, lifecycle, or the
# bucket itself.

resource "aws_s3_bucket" "fleet_backup" {
  bucket = "eleven-prod-fleet-backup-${local.account_id}"
}

resource "aws_s3_bucket_versioning" "fleet_backup" {
  bucket = aws_s3_bucket.fleet_backup.id

  versioning_configuration {
    status = "Enabled"
  }
}

resource "aws_s3_bucket_lifecycle_configuration" "fleet_backup" {
  bucket = aws_s3_bucket.fleet_backup.id

  rule {
    id     = "expire-noncurrent-14d"
    status = "Enabled"

    filter {}

    noncurrent_version_expiration {
      noncurrent_days = 14
    }
  }
}

resource "aws_s3_bucket_public_access_block" "fleet_backup" {
  bucket = aws_s3_bucket.fleet_backup.id

  block_public_acls       = true
  block_public_policy     = true
  ignore_public_acls      = true
  restrict_public_buckets = true
}

# TLS-only: deny any request arriving over plain HTTP. Litestream and the
# vault sync both speak HTTPS already — this turns that assumption into
# policy. A deny-only statement grants nothing public, so it attaches fine
# under the full access block above.
data "aws_iam_policy_document" "fleet_backup_tls_only" {
  statement {
    sid     = "DenyInsecureTransport"
    effect  = "Deny"
    actions = ["s3:*"]
    resources = [
      aws_s3_bucket.fleet_backup.arn,
      "${aws_s3_bucket.fleet_backup.arn}/*",
    ]

    principals {
      type        = "*"
      identifiers = ["*"]
    }

    condition {
      test     = "Bool"
      variable = "aws:SecureTransport"
      values   = ["false"]
    }
  }
}

resource "aws_s3_bucket_policy" "fleet_backup" {
  bucket = aws_s3_bucket.fleet_backup.id
  policy = data.aws_iam_policy_document.fleet_backup_tls_only.json
}

# The router box's credentials: object read/write/delete + list on the fleet
# bucket, nothing else in the account. Mint the access key by hand
# (aws iam create-access-key --user-name litestream-fleet) — keys never land
# in tofu state.
resource "aws_iam_user" "litestream_fleet" {
  name = "litestream-fleet"
}

data "aws_iam_policy_document" "litestream_fleet" {
  statement {
    sid       = "ListFleetBucket"
    actions   = ["s3:ListBucket"]
    resources = [aws_s3_bucket.fleet_backup.arn]
  }

  statement {
    sid = "ReadWriteFleetObjects"
    actions = [
      "s3:GetObject",
      "s3:PutObject",
      "s3:DeleteObject",
    ]
    resources = ["${aws_s3_bucket.fleet_backup.arn}/*"]
  }
}

resource "aws_iam_user_policy" "litestream_fleet" {
  name   = "litestream-fleet-bucket"
  user   = aws_iam_user.litestream_fleet.name
  policy = data.aws_iam_policy_document.litestream_fleet.json
}