package usecase

import (
	"context"
	"fmt"
	"strings"

	"go.maximumdirect.net/promptkit/internal/domain"
)

type resolvedPromptDefinition struct {
	definition *domain.PromptDefinition
	hash       string
}

func (r *Runner) resolvePromptDefinition(ctx context.Context, promptID string) (*resolvedPromptDefinition, error) {
	if strings.TrimSpace(promptID) == "" {
		return nil, fmt.Errorf("%w: prompt id is required", ErrInvalidRequest)
	}
	if r == nil || r.promptDefs == nil {
		return nil, fmt.Errorf("%w: prompt repository is not configured", ErrPromptLoad)
	}

	definition, hash, err := r.promptDefs.GetPromptSnapshot(ctx, promptID)
	if err != nil {
		return nil, promptLookupError(err)
	}
	if definition == nil {
		return nil, fmt.Errorf("%w: prompt repository returned nil definition", ErrPromptLoad)
	}

	return &resolvedPromptDefinition{definition: definition, hash: hash}, nil
}

func (r *Runner) resolvePromptInspection(ctx context.Context, promptID string) (*domain.PromptInspection, error) {
	if strings.TrimSpace(promptID) == "" {
		return nil, fmt.Errorf("%w: prompt id is required", ErrInvalidRequest)
	}
	if r == nil || r.promptDefs == nil {
		return nil, fmt.Errorf("%w: prompt repository is not configured", ErrPromptLoad)
	}
	inspection, err := r.promptDefs.GetPromptInspection(ctx, promptID)
	if err != nil {
		return nil, promptLookupError(err)
	}
	if inspection == nil {
		return nil, fmt.Errorf("%w: prompt repository returned nil inspection", ErrPromptLoad)
	}
	return inspection, nil
}

// InspectPrompt resolves one explicit prompt without execution work.
func (r *Runner) InspectPrompt(ctx context.Context, promptID string) (*domain.PromptInspection, error) {
	if strings.TrimSpace(promptID) == "" {
		return nil, fmt.Errorf("%w: prompt id is required", ErrInvalidRequest)
	}
	select {
	case <-ctx.Done():
		return nil, &OperationError{Category: ErrPromptLoad, Cause: ctx.Err()}
	default:
	}

	return r.resolvePromptInspection(ctx, promptID)
}