terraform {
  backend "s3" {
    region         = "ca-central-1"
    bucket         = "rekahsoft-terraform"
    key            = "blog-rekahsoft-ca/blog-rekahsoft-ca.tfstate"
    dynamodb_table = "rekahsoft-terraform"
  }
}

provider "aws" {
  region  = "${var.region}"
  version = "~> 1.9"

  assume_role = [{
    role_arn = "${var.workspace_iam_roles[terraform.workspace]}"
  }]
}

provider "aws" {
  alias   = "us_east_1"
  region  = "us-east-1"
  version = "~> 1.9"

  assume_role = [{
    role_arn = "${var.workspace_iam_roles[terraform.workspace]}"
  }]
}

provider "null" {
  version = "~> 1.0"
}

provider "random" {
  version = "~> 1.3"
}

provider "template" {
  version = "~> 1.0"
}

#
# Local values to be re-used throughout this template

locals {
  common_tags = "${map(
    "Project", "${var.project}",
    "Environment", "${terraform.workspace}"
  )}"
  cdn_origin_id     = "${terraform.workspace}-origin-cdn"
  www               = "${var.enable_naked_domain ? "" : "www."}"
  subdomain         = "${var.subdomain == "" ? "" : "${var.subdomain}."}"
  naked_domain      = "${local.subdomain}${var.dns_apex}"
  domain            = "${local.www}${local.naked_domain}"
  project_env       = "${var.project}-${terraform.workspace}"
}


#
# Data Sources

data "template_file" "s3_origin_policy" {
  template = "${file("templates/s3_origin_policy.json")}"

  vars {
    bucket_arn     = "${aws_s3_bucket.static.arn}"
    user_arn       = "${aws_iam_user.app_deploy.arn}"
    cloudfront_arn = "${aws_cloudfront_origin_access_identity.origin_access_identity.iam_arn}"
  }
}

data "aws_route53_zone" "external" {
  name   = "${var.dns_apex}."
}


#
# Resources

resource "aws_acm_certificate" "cert" {
  domain_name               = "${local.domain}"
  subject_alternative_names = "${compact(list("${var.enable_naked_domain}" ? "" : "${local.naked_domain}"))}"
  validation_method         = "DNS"
  tags                      = "${local.common_tags}"

  provider = "aws.us_east_1"
}

resource "aws_route53_record" "cert_validation" {
  count = "${1 + "${var.enable_naked_domain ? 0 : 1}"}"

  zone_id = "${data.aws_route53_zone.external.id}"
  name    = "${lookup(aws_acm_certificate.cert.domain_validation_options[count.index], "resource_record_name")}"
  type    = "${lookup(aws_acm_certificate.cert.domain_validation_options[count.index], "resource_record_type")}"
  ttl     = 60
  records = ["${lookup(aws_acm_certificate.cert.domain_validation_options[count.index], "resource_record_value")}"]
}

resource "aws_acm_certificate_validation" "cert" {
  certificate_arn = "${aws_acm_certificate.cert.arn}"
  validation_record_fqdns = ["${aws_route53_record.cert_validation.*.fqdn}"]

  provider = "aws.us_east_1"
}

resource "aws_s3_bucket" "static" {
  bucket_prefix = "${local.project_env}"
  acl           = "private"

  website {
    index_document = "index.html"
    error_document = "error.html"
  }

  tags = "${local.common_tags}"
}

resource "aws_s3_bucket" "static_redirect" {
  count = "${var.enable_naked_domain ? 0 : 1}"

  bucket_prefix = "${local.project_env}"
  acl           = "private"

  website {
    redirect_all_requests_to = "https://${local.domain}"
  }

  tags = "${local.common_tags}"
}

resource "aws_s3_bucket" "static_logs" {
  bucket_prefix = "${local.project_env}"
  acl           = "private"
}

resource "random_string" "app_deploy_username" {
  length = 16
  special = true
  override_special = "_+=,.@-"
}

resource "aws_iam_user" "app_deploy" {
  name = "${random_string.app_deploy_username.result}"
}

resource "aws_iam_access_key" "app_deploy" {
  user    = "${aws_iam_user.app_deploy.name}"
#  pgp_key = "keybase:some_person_that_exists"
}

resource "aws_route53_record" "static" {
  zone_id = "${data.aws_route53_zone.external.zone_id}"
  name    = "${local.domain}."
  type    = "A"

  alias {
    name                   = "${aws_cloudfront_distribution.cdn.domain_name}"
    zone_id                = "${aws_cloudfront_distribution.cdn.hosted_zone_id}"
    evaluate_target_health = true
  }
}

resource "aws_route53_record" "static_redirect" {
  count = "${var.enable_naked_domain ? 0 : 1}"

  zone_id = "${data.aws_route53_zone.external.zone_id}"
  name    = "${local.naked_domain}."
  type    = "A"

  alias {
    name                   = "${aws_cloudfront_distribution.cdn_redirect.domain_name}"
    zone_id                = "${aws_cloudfront_distribution.cdn_redirect.hosted_zone_id}"
    evaluate_target_health = true
  }
}

resource "aws_s3_bucket_policy" "static_policy" {
  bucket = "${aws_s3_bucket.static.id}"
  policy = "${data.template_file.s3_origin_policy.rendered}"
}

resource "aws_cloudfront_origin_access_identity" "origin_access_identity" {
  comment = "Origin access policy for ${local.project_env}"
}

resource "aws_cloudfront_distribution" "cdn" {
  # Static file origin
  origin {
    domain_name = "${aws_s3_bucket.static.bucket_regional_domain_name}"
    origin_id   = "${local.cdn_origin_id}"

    s3_origin_config {
      origin_access_identity = "${aws_cloudfront_origin_access_identity.origin_access_identity.cloudfront_access_identity_path}"
    }
  }

  enabled             = true
  is_ipv6_enabled     = true
  comment             = "CDN for ${var.project} (environment ${terraform.workspace})"
  default_root_object = "index.html"

  # Return index.html for any route that is not found
  custom_error_response {
    error_caching_min_ttl = 0
    error_code = 403
    response_code = 200
    response_page_path = "/index.html"
  }

  logging_config {
    include_cookies = false
    bucket          = "${aws_s3_bucket.static_logs.bucket_domain_name}"
  }

  aliases = ["${local.domain}"]

  default_cache_behavior {
    allowed_methods  = ["GET", "HEAD", "OPTIONS"]
    cached_methods   = ["GET", "HEAD", "OPTIONS"]
    target_origin_id = "${local.cdn_origin_id}"

    forwarded_values {
      query_string = false

      cookies {
        forward = "none"
      }
    }

    min_ttl                = 0
    default_ttl            = 3600
    max_ttl                = 86400
    viewer_protocol_policy = "redirect-to-https"
  }

  # Cache behavior with precedence 0
  ordered_cache_behavior {
    path_pattern     = "index.html"
    allowed_methods  = ["GET", "HEAD", "OPTIONS"]
    cached_methods   = ["GET", "HEAD", "OPTIONS"]
    target_origin_id = "${local.cdn_origin_id}"

    forwarded_values {
      query_string = false
      headers = ["Origin"]
      cookies {
        forward = "none"
      }
    }

    min_ttl                = 0
    default_ttl            = 0
    max_ttl                = 0
    compress               = true
    viewer_protocol_policy = "redirect-to-https"
  }

  price_class = "PriceClass_100"

  restrictions {
    geo_restriction {
      restriction_type = "none"
    }
  }

  tags = "${local.common_tags}"

  viewer_certificate {
    acm_certificate_arn      = "${aws_acm_certificate_validation.cert.certificate_arn}"
    ssl_support_method       = "sni-only"
    minimum_protocol_version = "TLSv1.1_2016"
  }
}

resource "aws_cloudfront_distribution" "cdn_redirect" {
  count = "${var.enable_naked_domain ? 0 : 1}"

  # Static file origin
  origin {
    domain_name = "${aws_s3_bucket.static_redirect.id}.${aws_s3_bucket.static_redirect.website_domain}"
    origin_id   = "${local.cdn_origin_id}"

    custom_origin_config {
      http_port = 80
      https_port = 443

      origin_ssl_protocols   = ["TLSv1.1", "TLSv1.2"]
      origin_protocol_policy = "http-only"
    }
  }

  enabled             = true
  is_ipv6_enabled     = true
  comment             = "CDN redirect for ${var.project} (environment ${terraform.workspace})"

  logging_config {
    include_cookies = false
    bucket          = "${aws_s3_bucket.static_logs.bucket_domain_name}"
  }

  aliases = ["${local.naked_domain}"]

  default_cache_behavior {
    allowed_methods  = ["GET", "HEAD", "OPTIONS"]
    cached_methods   = ["GET", "HEAD", "OPTIONS"]
    target_origin_id = "${local.cdn_origin_id}"

    forwarded_values {
      query_string = false

      cookies {
        forward = "none"
      }
    }

    min_ttl                = 0
    default_ttl            = 3600
    max_ttl                = 86400
    viewer_protocol_policy = "redirect-to-https"
  }

  price_class = "PriceClass_100"

  restrictions {
    geo_restriction {
      restriction_type = "none"
    }
  }

  tags = "${local.common_tags}"

  viewer_certificate {
    acm_certificate_arn      = "${aws_acm_certificate_validation.cert.certificate_arn}"
    ssl_support_method       = "sni-only"
    minimum_protocol_version = "TLSv1.1_2016"
  }
}

resource "null_resource" "deploy_app" {
  provisioner "local-exec" {
    interpreter = ["bash", "-c"]
    command = <<SCRIPT
: Add default AWS account profile;
aws configure --profile ${aws_iam_user.app_deploy.name} set aws_access_key_id ${aws_iam_access_key.app_deploy.id};
aws configure --profile ${aws_iam_user.app_deploy.name} set aws_secret_access_key ${aws_iam_access_key.app_deploy.secret};
aws configure --profile ${aws_iam_user.app_deploy.name} set region ${var.region};

: Sync latest app build to s3 bucket;
aws --profile ${aws_iam_user.app_deploy.name} s3 sync --delete ../_site s3://${aws_s3_bucket.static.id}/;
SCRIPT
  }
}