package checker

import (
	"time"

	sdk "git.happydns.org/checker-sdk-go/checker"
)

// Version is the checker version reported in CheckerDefinition.Version.
var Version = "built-in"

// Definition returns the CheckerDefinition for the alias checker.
func Definition() *sdk.CheckerDefinition {
	def := &sdk.CheckerDefinition{
		ID:      "alias",
		Name:    "CNAME / DNAME / ALIAS chain",
		Version: Version,
		Availability: sdk.CheckerAvailability{
			ApplyToService: true,
			ApplyToDomain:  true,
			ApplyToZone:    true,
			LimitToServices: []string{
				"svcs.CNAME",
				"svcs.SpecialCNAME",
			},
		},
		ObservationKeys: []sdk.ObservationKey{ObservationKeyAlias},
		Options: sdk.CheckerOptionsDocumentation{
			UserOpts: []sdk.CheckerOptionDocumentation{
				{
					Id:          "maxChainLength",
					Type:        "uint",
					Label:       "Maximum chain length",
					Description: "Above this number of hops the chain is reported as critical. Most resolvers give up around 8-16.",
					Default:     float64(8),
				},
				{
					Id:          "minTargetTTL",
					Type:        "uint",
					Label:       "Minimum TTL (seconds)",
					Description: "Hops with a TTL below this threshold are flagged as a warning. Very short TTLs degrade cache performance.",
					Default:     float64(60),
				},
				{
					Id:          "requireResolvableTarget",
					Type:        "bool",
					Label:       "Require resolvable target",
					Description: "When enabled, a chain whose final target returns no A/AAAA is reported as critical (otherwise a warning).",
					Default:     true,
				},
				{
					Id:          "allowApexCNAME",
					Type:        "bool",
					Label:       "Allow CNAME at apex",
					Description: "When enabled, a CNAME at a zone apex is only reported as warning. RFC 1912 forbids this, so leaving it off is strongly recommended.",
					Default:     false,
				},
				{
					Id:          "recognizeApexFlattening",
					Type:        "bool",
					Label:       "Recognize ALIAS/ANAME flattening",
					Description: "When enabled, providers that serve A/AAAA at the apex (ALIAS/ANAME pseudo-records) are reported as informational instead of a coexistence violation.",
					Default:     true,
				},
			},
			DomainOpts: []sdk.CheckerOptionDocumentation{
				{
					Id:       "domain_name",
					Label:    "Parent domain name",
					AutoFill: sdk.AutoFillDomainName,
				},
				{
					Id:       "subdomain",
					Label:    "Subdomain",
					AutoFill: sdk.AutoFillSubdomain,
				},
			},
			ServiceOpts: []sdk.CheckerOptionDocumentation{
				{
					Id:       "service_type",
					Label:    "Service type",
					AutoFill: sdk.AutoFillServiceType,
				},
				{
					Id:       "service",
					Label:    "Service",
					AutoFill: sdk.AutoFillService,
				},
			},
		},
		Rules: []sdk.CheckRule{
			Rule(),
		},
		HasHTMLReport: true,
		Interval: &sdk.CheckIntervalSpec{
			Min:     5 * time.Minute,
			Max:     24 * time.Hour,
			Default: 1 * time.Hour,
		},
	}
	def.BuildRulesInfo()
	return def
}