# HTTP API fronting the order form.
#
# Three authorization modes coexist, matching template.yaml:
#   NONE     — the public form routes (submit-order, form-status, roster)
#   AWS_IAM  — the weekly-menu publication routes, called with SigV4 by
#              scripts/upload_menu.py from GitHub Actions
#   CUSTOM   — every /api/admin route, behind the Google ID token authorizer
#
# All nine routes integrate with submit-order, which dispatches internally on
# the route key.

resource "aws_apigatewayv2_api" "order_api" {
  name          = local.project
  protocol_type = "HTTP"
  description   = "meal-order-manager order form and admin API"

  # Only the production origin. Local development uses the Flask dev server in
  # app.py, which proxies API calls and does not enforce CORS.
  cors_configuration {
    allow_origins = [local.form_url]
    allow_methods = ["GET", "POST", "PUT", "DELETE", "OPTIONS"]
    allow_headers = ["Content-Type", "Authorization"]
    max_age       = 3600
  }
}

# Result caching is off. With caching, an expired Google token or an admin
# removed from the allow-list would stay authorized for the cache TTL, and the
# tokeninfo call dominates latency anyway.
resource "aws_apigatewayv2_authorizer" "admin_google" {
  api_id                            = aws_apigatewayv2_api.order_api.id
  name                              = "AdminGoogleAuthorizer"
  authorizer_type                   = "REQUEST"
  authorizer_uri                    = aws_lambda_function.admin_authorizer.invoke_arn
  authorizer_credentials_arn        = aws_iam_role.admin_authorizer_invoke.arn
  authorizer_payload_format_version = "2.0"
  authorizer_result_ttl_in_seconds  = 0
  enable_simple_responses           = true
  identity_sources                  = ["$request.header.Authorization"]
}

resource "aws_apigatewayv2_integration" "submit_order" {
  api_id                 = aws_apigatewayv2_api.order_api.id
  integration_type       = "AWS_PROXY"
  integration_method     = "POST"
  integration_uri        = aws_lambda_function.submit_order.invoke_arn
  payload_format_version = "2.0"
  timeout_milliseconds   = 30000
}

resource "aws_apigatewayv2_route" "this" {
  for_each = local.api_routes

  api_id    = aws_apigatewayv2_api.order_api.id
  route_key = each.value.route_key
  target    = "integrations/${aws_apigatewayv2_integration.submit_order.id}"

  authorization_type = each.value.authorizer
  authorizer_id      = each.value.authorizer == "CUSTOM" ? aws_apigatewayv2_authorizer.admin_google.id : null
}

resource "aws_apigatewayv2_stage" "default" {
  api_id      = aws_apigatewayv2_api.order_api.id
  name        = "$default"
  auto_deploy = true

  access_log_settings {
    destination_arn = aws_cloudwatch_log_group.api_access.arn
    format          = "{\"requestId\":\"$context.requestId\",\"ip\":\"$context.identity.sourceIp\",\"requestTime\":\"$context.requestTime\",\"method\":\"$context.httpMethod\",\"routeKey\":\"$context.routeKey\",\"status\":\"$context.status\",\"protocol\":\"$context.protocol\",\"responseLength\":\"$context.responseLength\",\"integrationError\":\"$context.integrationErrorMessage\"}"
  }

  default_route_settings {
    throttling_burst_limit = 50
    throttling_rate_limit  = 100
  }

  # Order submission is human-paced; menu publication runs once a week. Both are
  # throttled well below the account default so a loop in either client cannot
  # exhaust the API's burst budget for the public form.
  route_settings {
    route_key              = "POST /api/submit-order"
    throttling_burst_limit = 10
    throttling_rate_limit  = 5
  }

  route_settings {
    route_key              = "POST /api/publish/menu"
    throttling_burst_limit = 2
    throttling_rate_limit  = 1
  }

  depends_on = [aws_apigatewayv2_route.this]
}

# One grant per route rather than a single wildcard, so adding a route to the
# API does not silently make the function invocable through it.
resource "aws_lambda_permission" "api_route" {
  for_each = local.api_routes

  statement_id  = "AllowApiGatewayInvoke-${each.key}"
  action        = "lambda:InvokeFunction"
  function_name = aws_lambda_function.submit_order.function_name
  principal     = "apigateway.amazonaws.com"
  source_arn    = "${aws_apigatewayv2_api.order_api.execution_arn}/*/${each.value.permission_source}"
}