package inquiry

import (
	"errors"
	"fmt"
	"strings"
)

// Inquiry-specific errors
var (
	ErrDuplicateInquiryByEmail = errors.New("duplicate inquiry by email")
	ErrDuplicateInquiryByPhone = errors.New("duplicate inquiry by phone")
	ErrInquiryNotFound         = errors.New("inquiry not found")
	ErrInvalidStatusTransition = errors.New("invalid status transition")
	ErrInquiryAlreadyProcessed = errors.New("inquiry already processed")
)

// DuplicateInquiryError represents a duplicate inquiry error with details
type DuplicateInquiryError struct {
	Type        string `json:"type"`        // "email" or "phone"
	ExistingID  string `json:"existing_id"` // ID of existing inquiry
	Status      string `json:"status"`      // Status of existing inquiry
	CreatedAt   int64  `json:"created_at"`  // When existing inquiry was created
	Message     string `json:"message"`     // User-friendly message
}

func (e *DuplicateInquiryError) Error() string {
	return e.Message
}

// NewDuplicateInquiryError creates a new duplicate inquiry error
// InvalidStatusTransitionError is returned when an inquiry status change is not allowed.
type InvalidStatusTransitionError struct {
	CurrentStatus string
	NewStatus     string
	Allowed       []string
}

func (e *InvalidStatusTransitionError) Error() string {
	if len(e.Allowed) == 0 {
		return fmt.Sprintf("Inquiry status is already %s and cannot be changed", e.CurrentStatus)
	}
	return fmt.Sprintf(
		"Cannot change inquiry status from %s to %s. Allowed next statuses: %s",
		e.CurrentStatus,
		e.NewStatus,
		strings.Join(e.Allowed, ", "),
	)
}

// NewInvalidStatusTransitionError creates a status transition error with allowed next statuses.
func NewInvalidStatusTransitionError(currentStatus, newStatus string, allowed []string) *InvalidStatusTransitionError {
	return &InvalidStatusTransitionError{
		CurrentStatus: currentStatus,
		NewStatus:     newStatus,
		Allowed:       allowed,
	}
}

func NewDuplicateInquiryError(inquiryType, existingID, status string, createdAt int64) *DuplicateInquiryError {
	var message string
	if inquiryType == "email" {
		message = "You already have a pending inquiry with this email address. Please wait for it to be processed before submitting a new one."
	} else {
		message = "A pending inquiry already exists with this phone number. Please wait for it to be processed before submitting a new one."
	}

	return &DuplicateInquiryError{
		Type:       inquiryType,
		ExistingID: existingID,
		Status:     status,
		CreatedAt:  createdAt,
		Message:    message,
	}
}