package sourcerefs

import (
	"context"
	"fmt"

	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd/validate/spells/spellpayload"
)

const Key = "extract/dnd/spells/source_refs"
const ReasonCode = "invalid_source_refs"

var _ contracts.LegacyRawValidator = (*Validator)(nil)

type Validator struct{}

func New() *Validator {
	return &Validator{}
}

func (v *Validator) Name() string {
	return Key
}

func (v *Validator) ExecutionClass() contracts.ExecutionClass {
	return contracts.ExecutionClassDeterministic
}

func (v *Validator) Validate(ctx context.Context, req contracts.ValidationRequest) (contracts.ValidationResult, error) {
	payload, err := spellpayload.ValidationRequestPayload(req)
	if err != nil {
		return rejection(err.Error()), nil
	}
	if err := spellpayload.ValidateShape(payload); err != nil {
		return rejection(err.Error()), nil
	}
	for spellIndex, spell := range payload.SpellCasts {
		for refIndex, ref := range spellpayload.SourceRefCandidates(req.Source, spell) {
			if err := source.ValidateRef(req.Source, ref); err != nil {
				return rejection(fmt.Sprintf("spell_casts[%d].source_refs[%d]: %v", spellIndex, refIndex, err)), nil
			}
		}
	}
	return contracts.ValidationResult{Approved: true}, nil
}

func Spec() pipeline.ValidatorSpec {
	return pipeline.ValidatorSpec{
		Key:            Key,
		ExecutionClass: contracts.ExecutionClassDeterministic,
	}
}

func Register(registry *pipeline.ValidatorRegistry) error {
	return registry.RegisterLegacyRawWithSpec(Spec(), func() (contracts.LegacyRawValidator, error) {
		return New(), nil
	})
}

func rejection(message string) contracts.ValidationResult {
	return contracts.ValidationResult{
		Approved:   false,
		ReasonCode: ReasonCode,
		Message:    message,
	}
}