# VPC peering connections ====================================================

resource "aws_vpc_peering_connection" "this" {
  for_each = var.peering_connections

  vpc_id        = each.value.requester_vpc_id
  peer_vpc_id   = each.value.peer_vpc_id
  peer_owner_id = each.value.peer_account_id
  peer_region   = each.value.peer_region
  auto_accept   = each.value.auto_accept

  requester {
    allow_remote_vpc_dns_resolution = each.value.allow_remote_vpc_dns
  }

  tags = merge(local.tags, { Name = each.key })
}

# Peering accepter (same-account, no cross-region provider alias) ------------

resource "aws_vpc_peering_connection_accepter" "this" {
  for_each = {
    for k, v in var.peering_connections : k => v
    if !v.auto_accept && v.peer_account_id == null
  }

  vpc_peering_connection_id = aws_vpc_peering_connection.this[each.key].id
  auto_accept               = true

  accepter {
    allow_remote_vpc_dns_resolution = each.value.allow_remote_vpc_dns
  }

  tags = merge(local.tags, { Name = "${each.key}-accepter" })
}

# Requester-side routes ------------------------------------------------------

resource "aws_route" "requester" {
  for_each = local.requester_route_map

  route_table_id            = each.value.rt
  destination_cidr_block    = each.value.cidr
  vpc_peering_connection_id = aws_vpc_peering_connection.this[each.value.pk].id

  depends_on = [aws_vpc_peering_connection_accepter.this]
}

# Accepter-side routes -------------------------------------------------------

resource "aws_route" "accepter" {
  for_each = local.accepter_route_map

  route_table_id            = each.value.rt
  destination_cidr_block    = each.value.cidr
  vpc_peering_connection_id = aws_vpc_peering_connection.this[each.value.pk].id

  depends_on = [aws_vpc_peering_connection_accepter.this]
}