packer {
  required_plugins {
    virtualbox = {
      version = ">= 1.1.0"
      source  = "github.com/hashicorp/virtualbox"
    }
  }
}

variable "vm_name" {
  type    = string
  default = "haskell-build"
}

variable "disk_size" {
  type    = number
  default = 40960
}

variable "memory" {
  type    = number
  default = 8192
}

variable "cpus" {
  type    = number
  default = 4
}

variable "ghc_primary_version" {
  type    = string
  default = "9.8.4"
}

variable "ghc_secondary_version" {
  type    = string
  default = "9.6.6"
}

variable "cabal_version" {
  type    = string
  default = "3.12.1.0"
}

variable "iso_url" {
  type    = string
  default = "https://releases.ubuntu.com/24.04/ubuntu-24.04.2-live-server-amd64.iso"
}

variable "iso_checksum" {
  type    = string
  default = "sha256:d6dab0c3a657988501b4bd76f1297c053df710e06e0c3aece60dead24f270b4d"
}

locals {
  timestamp = formatdate("YYYYMMDD", timestamp())
}

source "virtualbox-iso" "haskell-build" {
  vm_name              = var.vm_name
  guest_os_type        = "Ubuntu_64"
  disk_size            = var.disk_size
  hard_drive_interface = "sata"

  memory = var.memory
  cpus   = var.cpus

  iso_url      = var.iso_url
  iso_checksum = var.iso_checksum

  # NAT during build — Packer needs internet for ISO + packages.
  # Bridged networking is set post-import by setup-vm.sh (adapter names
  # are laptop-specific and cannot be baked into the image).
  vboxmanage = [
    ["modifyvm", "{{.Name}}", "--nat-localhostreachable1", "on"],
  ]

  http_directory = "files/cloud-init"

  boot_wait = "5s"
  boot_command = [
    "c<wait>",
    "linux /casper/vmlinuz --- autoinstall ds='nocloud;s=http://{{.HTTPIP}}:{{.HTTPPort}}/'<enter><wait>",
    "initrd /casper/initrd<enter><wait>",
    "boot<enter>",
  ]

  ssh_username         = "build"
  ssh_password         = "build"
  ssh_timeout          = "30m"
  ssh_handshake_attempts = 100
  shutdown_command      = "echo 'build' | sudo -S shutdown -P now"

  # File provisioners — stage agent files before install script runs
  # (Packer uploads to /tmp by default for file provisioners)

  output_directory = "output-${var.vm_name}"
  output_filename  = "${var.vm_name}"
}

build {
  sources = ["source.virtualbox-iso.haskell-build"]

  # Stage agent files to /tmp (install-agent.sh moves them into place)
  provisioner "file" {
    source      = "files/build-agent.py"
    destination = "/tmp/build-agent.py"
  }

  provisioner "file" {
    source      = "files/build-agent.service"
    destination = "/tmp/build-agent.service"
  }

  provisioner "file" {
    source      = "files/build-agent.env.template"
    destination = "/tmp/build-agent.env.template"
  }

  # Install Haskell toolchain (GHCup + GHC + Cabal)
  provisioner "shell" {
    execute_command = "echo 'build' | sudo -S env {{ .Vars }} bash '{{ .Path }}'"
    script          = "scripts/install-haskell.sh"
    environment_vars = [
      "GHC_PRIMARY_VERSION=${var.ghc_primary_version}",
      "GHC_SECONDARY_VERSION=${var.ghc_secondary_version}",
      "CABAL_VERSION=${var.cabal_version}",
    ]
  }

  # Install build-agent + systemd unit
  provisioner "shell" {
    execute_command = "echo 'build' | sudo -S env {{ .Vars }} bash '{{ .Path }}'"
    script          = "scripts/install-agent.sh"
  }

  # Export as OVA
  post-processor "vagrant" {
    only   = [] # disabled — we use the raw OVA below
  }

  post-processor "shell-local" {
    inline = [
      "cd output-${var.vm_name} && mv ${var.vm_name}.ova ../haskell-build-${local.timestamp}.ova || true",
    ]
  }
}