package checker

import (
	"context"
	"fmt"

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

// Rules returns the full list of CheckRules exposed by the PTR checker.
// Each rule covers one concern so callers can see at a glance which checks
// passed and which did not.
func Rules() []sdk.CheckRule {
	return []sdk.CheckRule{
		&reverseArpaRule{},
		&ownerDecodeRule{},
		&reverseZoneRule{},
		&queryOutcomeRule{},
		&ptrPresentRule{},
		&singlePTRRule{},
		&declaredMatchRule{},
		&targetSyntaxRule{},
		&genericHostnameRule{},
		&targetResolvesRule{},
		&fcrdnsMatchRule{},
		&ipv6PTRRule{},
		&ttlHygieneRule{},
	}
}

// loadPTR fetches the raw observation. On error, the returned CheckState is
// what the caller should emit to short-circuit.
func loadPTR(ctx context.Context, obs sdk.ObservationGetter) (*PTRData, *sdk.CheckState) {
	var data PTRData
	if err := obs.Get(ctx, ObservationKeyPTR, &data); err != nil {
		return nil, &sdk.CheckState{
			Status:  sdk.StatusError,
			Code:    "ptr.observation_error",
			Message: fmt.Sprintf("failed to get PTR data: %v", err),
		}
	}
	return &data, nil
}

func passState(code, message, subject string) sdk.CheckState {
	return sdk.CheckState{
		Status:  sdk.StatusOK,
		Code:    code,
		Message: message,
		Subject: subject,
	}
}

func skipState(code, message string) sdk.CheckState {
	return sdk.CheckState{
		Status:  sdk.StatusUnknown,
		Code:    code,
		Message: message,
	}
}

func critState(code, message, subject, hint string) sdk.CheckState {
	return withHint(sdk.CheckState{
		Status:  sdk.StatusCrit,
		Code:    code,
		Message: message,
		Subject: subject,
	}, hint)
}

func warnState(code, message, subject, hint string) sdk.CheckState {
	return withHint(sdk.CheckState{
		Status:  sdk.StatusWarn,
		Code:    code,
		Message: message,
		Subject: subject,
	}, hint)
}

func withHint(st sdk.CheckState, hint string) sdk.CheckState {
	if hint != "" {
		st.Meta = map[string]any{"hint": hint}
	}
	return st
}