variable "users" {
  description = "List of userpass usernames to create."
  type        = list(string)
  default     = ["ms2k"]
}

variable "admin_user" {
  description = "Username from var.users to grant the admin policy. Used to establish non-root administrative access before revoking the initial root token."
  type        = string
  default     = "ms2k"

  validation {
    condition     = contains(var.users, var.admin_user)
    error_message = "admin_user must be present in var.users."
  }
}

# Auth method
resource "vault_auth_backend" "userpass" {
  type = "userpass"
}

# Admin policy
resource "vault_policy" "admin" {
  name = "admin"

  policy = <<-EOT
    path "*" {
      capabilities = ["create", "read", "update", "delete", "list", "sudo", "patch", "subscribe"]
      subscribe_event_types = ["*"]
    }
  EOT
}

# Users
resource "random_password" "user" {
  for_each = toset(var.users)
  length   = 32
  special  = false # alphanumeric only — avoids quoting issues when pasting into CLI
}

resource "vault_generic_endpoint" "user" {
  for_each = toset(var.users)

  path                 = "auth/${vault_auth_backend.userpass.path}/users/${each.key}"
  ignore_absent_fields = true

  # Terraform sets the initial password and policies on creation only.
  # Vault is the source of truth after that — re-runs won't reset passwords.
  lifecycle {
    ignore_changes = [data_json]
  }

  data_json = jsonencode({
    password = random_password.user[each.key].result
    policies = each.key == var.admin_user ? "admin" : ""
  })
}

# Outputs
output "user_passwords" {
  description = "Generated passwords keyed by username. Sensitive — retrieve with: tofu output -json user_passwords"
  sensitive   = true
  value = {
    for u in var.users : u => random_password.user[u].result
  }
}