package transformer

import (
	"encoding/json"
	"fmt"
	"strings"

	"github.com/yourorg/go-dw-platform/services/omnix-broadcast/domain"
	"github.com/yourorg/go-dw-platform/services/omnix-broadcast/entity"
)

type Transformer struct{}

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

func (t *Transformer) EntityToDomain(e *entity.BroadcastStaging) (*domain.Broadcast, error) {
	var payload map[string]any
	if err := json.Unmarshal(e.MessagePayload, &payload); err != nil {
		return nil, fmt.Errorf("unmarshal message_payload: %w", err)
	}

	return &domain.Broadcast{
		ID:                      e.ID,
		SopigaCollarID:          e.SopigaCollarID,
		SopigaTemplateID:        e.SopigaTemplateID,
		MessagePayload:          payload,
		Status:                  domain.BroadcastStatus(e.Status),
		ErrorMessage:            e.ErrorMessage,
		ErrorCount:              e.ErrorCount,
		SopigaRecipientDetailID: e.SopigaRecipientDetailID,
		CreatedAt:               e.CreatedAt,
		UpdatedAt:               e.UpdatedAt,
	}, nil
}

func (t *Transformer) EntityToDomainVariable(e *entity.TemplateVariableMapping) *domain.TemplateVariable {
	return &domain.TemplateVariable{
		VariableOrder: e.VariableOrder,
		VariableName:  e.SopigaVariableName,
		VariableType:  e.VariableType,
		FieldSource:   e.DBFieldSource,
		IsRequired:    e.IsRequired,
	}
}

// BuildDynamicMessage interpolates the message payload against the ordered
// template variables, joining formatted values with "#" — the delimiter
// Sopiga expects between positional template placeholders.
func (t *Transformer) BuildDynamicMessage(variables []*domain.TemplateVariable, payload map[string]any) (string, error) {
	parts := make([]string, 0, len(variables))

	for _, v := range variables {
		value, exists := payload[v.FieldSource]
		if !exists {
			if v.IsRequired {
				return "", fmt.Errorf("missing required field: %s", v.FieldSource)
			}
			value = ""
		}

		parts = append(parts, formatValue(v.VariableType, value))
	}

	return strings.Join(parts, "#"), nil
}

func formatValue(variableType string, value any) string {
	switch variableType {
	case "integer", "decimal":
		return fmt.Sprintf("%.0f", value)
	default:
		return fmt.Sprintf("%v", value)
	}
}