data "azurerm_client_config" "current" {}

locals {
  recovery_services_vault_name = (
    var.name != null &&
    trimspace(var.name) != "" ?
    var.name :
    "${coalesce(var.base_name, "")}${substr(md5("${data.azurerm_client_config.current.subscription_id}/${var.rg_name}/${coalesce(var.base_name, "")}"), 0, 6)}"
  )

  default_vm_backup_policies = {
    default = {
      name                           = "${local.recovery_services_vault_name}-vm-policy"
      policy_type                    = "V2"
      timezone                       = "UTC"
      instant_restore_retention_days = 5
      backup = {
        frequency = "Daily"
        time      = "23:00"
      }
      retention_daily = {
        count = 30
      }
      retention_weekly  = null
      retention_monthly = null
      retention_yearly  = null
    }
  }

  effective_vm_backup_policies = length(var.vm_backup_policies) > 0 ? {
    for key, policy in var.vm_backup_policies : key => {
      name                           = coalesce(try(policy.name, null), "${local.recovery_services_vault_name}-${key}-vm-policy")
      policy_type                    = coalesce(try(policy.policy_type, null), "V2")
      timezone                       = coalesce(try(policy.timezone, null), "UTC")
      instant_restore_retention_days = try(policy.instant_restore_retention_days, null)
      backup                         = policy.backup
      retention_daily                = try(policy.retention_daily, null)
      retention_weekly               = try(policy.retention_weekly, null)
      retention_monthly              = try(policy.retention_monthly, null)
      retention_yearly               = try(policy.retention_yearly, null)
    }
  } : (length(var.protected_vms) > 0 ? local.default_vm_backup_policies : {})

  default_vm_backup_policy_key = contains(keys(local.effective_vm_backup_policies), "default") ? "default" : (
    length(keys(local.effective_vm_backup_policies)) > 0 ? sort(keys(local.effective_vm_backup_policies))[0] : null
  )
}

resource "azurerm_recovery_services_vault" "this" {
  name                = local.recovery_services_vault_name
  location            = var.location
  resource_group_name = var.rg_name

  sku                          = var.sku
  storage_mode_type            = var.storage_mode_type
  cross_region_restore_enabled = var.cross_region_restore_enabled
  soft_delete_enabled          = var.soft_delete_enabled
  public_network_access_enabled = var.public_network_access_enabled
  immutability                 = var.immutability

  dynamic "identity" {
    for_each = var.identity == null ? [] : [var.identity]

    content {
      type         = identity.value.type
      identity_ids = try(identity.value.identity_ids, null)
    }
  }

  tags = var.tags
}

resource "azurerm_backup_policy_vm" "this" {
  for_each = local.effective_vm_backup_policies

  name                = each.value.name
  resource_group_name = var.rg_name
  recovery_vault_name = azurerm_recovery_services_vault.this.name

  policy_type                    = each.value.policy_type
  timezone                       = each.value.timezone
  instant_restore_retention_days = each.value.instant_restore_retention_days

  backup {
    frequency     = each.value.backup.frequency
    time          = each.value.backup.time
    hour_interval = try(each.value.backup.hour_interval, null)
    hour_duration = try(each.value.backup.hour_duration, null)
    weekdays      = try(each.value.backup.weekdays, null)
  }

  dynamic "retention_daily" {
    for_each = try(each.value.retention_daily, null) == null ? [] : [each.value.retention_daily]

    content {
      count = retention_daily.value.count
    }
  }

  dynamic "retention_weekly" {
    for_each = try(each.value.retention_weekly, null) == null ? [] : [each.value.retention_weekly]

    content {
      count    = retention_weekly.value.count
      weekdays = retention_weekly.value.weekdays
    }
  }

  dynamic "retention_monthly" {
    for_each = try(each.value.retention_monthly, null) == null ? [] : [each.value.retention_monthly]

    content {
      count             = retention_monthly.value.count
      weekdays          = try(retention_monthly.value.weekdays, null)
      weeks             = try(retention_monthly.value.weeks, null)
      days              = try(retention_monthly.value.days, null)
      include_last_days = try(retention_monthly.value.include_last_days, null)
    }
  }

  dynamic "retention_yearly" {
    for_each = try(each.value.retention_yearly, null) == null ? [] : [each.value.retention_yearly]

    content {
      count             = retention_yearly.value.count
      months            = retention_yearly.value.months
      weekdays          = try(retention_yearly.value.weekdays, null)
      weeks             = try(retention_yearly.value.weeks, null)
      days              = try(retention_yearly.value.days, null)
      include_last_days = try(retention_yearly.value.include_last_days, null)
    }
  }
}

resource "azurerm_backup_protected_vm" "this" {
  for_each = var.protected_vms

  resource_group_name = var.rg_name
  recovery_vault_name = azurerm_recovery_services_vault.this.name
  source_vm_id        = each.value.source_vm_id
  backup_policy_id    = azurerm_backup_policy_vm.this[coalesce(try(each.value.backup_policy_key, null), local.default_vm_backup_policy_key)].id

  include_disk_luns = try(each.value.include_disk_luns, null)
  exclude_disk_luns = try(each.value.exclude_disk_luns, null)
  protection_state  = try(each.value.protection_state, null)
}