# main.tf — 3 cloud-init'd Proxmox VE VMs (k3s-dev-1/2/3), each with an imported
# OS disk (from the Debian cloud image) and a blank Longhorn data disk (R-ENV-01).
#
# Node lifecycle stage 1 ("Create") per docs/02. cloud-init (infra/cloud-init/)
# does stage 2 ("Baseline"); Ansible (infra/ansible/) does stage 3 ("Cluster-join").
#
# Provider: bpg/proxmox. VMs land on the Proxmox node `var.proxmox_node`, disks on
# `var.datastore` (ZFS "Storage"), NIC on `var.bridge` (vmbr0), static IPs via the
# native cloud-init `initialization` block. The rich first-boot baseline (users,
# packages, kernel modules, Longhorn mount, swap-off) is delivered as a cloud-init
# user-data SNIPPET (see the snippets note in README / operator action below).

locals {
  # Per-node identity/addressing, KEYED BY NODE NAME (map, not list).
  # for_each over this map gives every node a stable, name-based state address
  # (…vm.node["k3s-dev-2"]) instead of a positional one. Positional count indexes
  # are brittle under -target/-replace: a single-node destroy on a count-indexed
  # resource can cascade to siblings (F1 finding). Name keys are individually
  # addressable, so one node can be replaced/destroyed without disturbing the others.
  nodes = {
    for i in range(var.node_count) : "${var.node_name_prefix}${i + 1}" => {
      name     = "${var.node_name_prefix}${i + 1}"
      ip       = var.node_ips[i]
      fqdn     = "${var.node_name_prefix}${i + 1}.${var.node_domain}"
      is_first = i == 0
    }
  }

  # Ordered (node1..nodeN) list + primary view for outputs that need positional
  # access — the resource for_each uses the map above; these preserve ordering for
  # the Ansible inventory (primary = cluster-init server, rest = secondaries).
  node_list = [for i in range(var.node_count) : local.nodes["${var.node_name_prefix}${i + 1}"]]
  primary   = local.nodes["${var.node_name_prefix}1"]
}

# --- base OS cloud image (downloaded once to `local`, imported per node) -----
# content_type "iso" stores it on the ISO datastore; the .img file name lets
# Proxmox accept the qcow2 (it still reads it as qcow2 on disk import).
resource "proxmox_virtual_environment_download_file" "debian_cloud_image" {
  content_type = "iso"
  datastore_id = var.image_datastore
  node_name    = var.proxmox_node
  url          = var.image_source
  file_name    = var.image_file_name
  overwrite    = false
}

# --- per-node cloud-init user-data snippet ----------------------------------
# bpg's native initialization.user_account only sets user/keys/password; it can't
# carry packages/write_files/runcmd. To preserve the full k3s/Cilium/Longhorn
# baseline we render the existing user-data.yaml.tftpl and ship it as a SNIPPET,
# referenced by the VM's initialization.user_data_file_id.
#
# OPERATOR ACTION: the `snippets` content type must be enabled on var.image_datastore
# (Datacenter -> Storage -> local -> Content -> add "Snippets"), else this file
# resource fails. See README "Operator prerequisites".
resource "proxmox_virtual_environment_file" "user_data" {
  for_each     = local.nodes
  content_type = "snippets"
  datastore_id = var.image_datastore
  node_name    = var.proxmox_node

  source_raw {
    file_name = "${each.value.name}-user-data.yaml"
    data = templatefile("${path.module}/../cloud-init/user-data.yaml.tftpl", {
      hostname           = each.value.name
      fqdn               = each.value.fqdn
      username           = var.login_user
      ssh_authorized_key = var.ssh_authorized_key
    })
  }
}

# --- the VMs ----------------------------------------------------------------
resource "proxmox_virtual_environment_vm" "node" {
  for_each  = local.nodes
  name      = each.value.name
  node_name = var.proxmox_node
  tags      = ["k3s", "k3s-dev", "opentofu"]

  description     = "k3s dev node ${each.value.name} (${each.value.fqdn}) — provisioned by OpenTofu."
  on_boot         = true
  stop_on_destroy = true

  # `host` CPU type passes through the physical CPU so nested virt is available for
  # KubeVirt in Phase 5.
  cpu {
    cores = var.vcpu
    type  = var.cpu_type
  }

  memory {
    dedicated = var.memory_mib
  }

  # qemu-guest-agent is installed by cloud-init; lets tofu/Proxmox read guest state.
  agent {
    enabled = true
  }

  operating_system {
    type = "l26"
  }

  # OS disk (virtio0 -> /dev/vda, boot): a copy of the imported cloud image, grown
  # to os_disk_gib. Longhorn data disk (virtio1 -> /dev/vdb): blank, data_disk_gib.
  # virtio* keeps the guest device names (/dev/vda, /dev/vdb) the cloud-init
  # fs_setup/mount for /var/lib/longhorn already expects.
  disk {
    datastore_id = var.datastore
    import_from  = proxmox_virtual_environment_download_file.debian_cloud_image.id
    interface    = "virtio0"
    size         = var.os_disk_gib
    discard      = "on"
  }

  disk {
    datastore_id = var.datastore
    interface    = "virtio1"
    size         = var.data_disk_gib
    discard      = "on"
  }

  network_device {
    bridge = var.bridge
  }

  # Static addressing + DNS come from cloud-init (bpg generates the network-config),
  # so the libvirt netplan template is gone. User-data (the baseline) is the snippet.
  initialization {
    datastore_id = var.datastore

    ip_config {
      ipv4 {
        address = "${each.value.ip}/${var.network_prefix}"
        gateway = var.network_gateway
      }
    }

    dns {
      servers = [var.dns_server]
    }

    user_data_file_id = proxmox_virtual_environment_file.user_data[each.key].id
  }

  # Boot from the OS disk only.
  boot_order = ["virtio0"]
}