resource "aws_iam_role" "instance_iam_role" {
  name               = "${var.environment}-${var.service_name}-asg-role"
  assume_role_policy = data.aws_iam_policy_document.assume_instance_role.json
}

resource "aws_iam_instance_profile" "iam_instance_profile" {
  name = "${var.environment}-${var.service_name}-asg-instance-profile"
  role = aws_iam_role.instance_iam_role.name
}

resource "aws_iam_policy" "instance_route53_policy" {
  name   = "${var.environment}-${var.service_name}-instance-route53-policy"
  policy = data.aws_iam_policy_document.instance_route53_policy.json
}

# Attach Route53 policy to instance role
resource "aws_iam_role_policy_attachment" "instance_route53_policy_attachment" {
  role       = aws_iam_role.instance_iam_role.name
  policy_arn = aws_iam_policy.instance_route53_policy.arn
}

resource "aws_iam_policy" "instance_tag_policy" {
  name   = "${var.environment}-${var.service_name}-instance-tag-policy"
  policy = data.aws_iam_policy_document.instance_tag_policy.json
}

# Attach instance tag policy to instance role
resource "aws_iam_role_policy_attachment" "instance_tag_policy_attachment" {
  role       = aws_iam_role.instance_iam_role.name
  policy_arn = aws_iam_policy.instance_tag_policy.arn
}

# Attach Datadog policy to instance role (used for refresh scripts)
resource "aws_iam_role_policy_attachment" "neo4j_datadog_policy_attachment" {
  role       = aws_iam_role.instance_iam_role.name
  policy_arn = "arn:aws:iam::${data.aws_caller_identity.current.account_id}:policy/SecretsManager-${var.environment}-datadog-policy"
}

# Policy for instance role to allow tag modifications (Chef)
data "aws_iam_policy_document" "instance_tag_policy" {
  statement {
    effect    = "Allow"
    resources = [
      "arn:aws:ec2:${var.aws_region}:${data.aws_caller_identity.current.account_id}:instance/*",
    ]

    actions = [
      "ec2:CreateTags",
      "ec2:DeleteTags",
    ]
  }

  statement {
    effect    = "Allow"
    resources = [
      "*"
    ]

    actions = [
      "ec2:Describe*",
    ]
  }
}

# Policy for instance role to allow Route53 record creation (Chef)
data "aws_iam_policy_document" "instance_route53_policy" {
  statement {
    effect    = "Allow"
    resources = [
      "*",
    ]

    actions = [
      "route53:ListHostedZones"
    ]
  }

  statement {
    effect    = "Allow"
    resources = [
      "arn:aws:route53:::hostedzone/${var.route53_zone_id}",
    ]

    actions = [
      "route53:GetHostedZone",
      "route53:ChangeResourceRecordSets",
      "route53:ListResourceRecordSets",
    ]
  }
}

data "aws_iam_policy_document" "assume_instance_role" {
  statement {
    actions = [
      "sts:AssumeRole",
    ]

    principals {
      type        = "Service"
      identifiers = [
        "ec2.amazonaws.com",
      ]
    }
  }
}