Add Tender Approval Management Functionality and API Enhancements

- Introduced a new tender approval management system, including the creation of tender approval entities, services, and repositories.
- Implemented CRUD operations for tender approvals, allowing companies to approve or reject tenders.
- Developed administrative and public API endpoints for listing, retrieving, and updating tender approvals with comprehensive filtering options.
- Enhanced Swagger documentation to accurately reflect the new endpoints, including detailed descriptions, parameters, and response formats.
- Updated existing routes to include tender approval management, ensuring adherence to Clean Architecture principles and maintaining a clear separation of concerns in the handler layer.

internal/tender_approval/validation.go

@@ -0,0 +1,176 @@
+package tender_approval
+
+import (
+	"regexp"
+	"strings"
+)
+
+// Validation functions for tender approval domain
+
+// IsValidTenderID validates if the tender ID format is correct
+func IsValidTenderID(tenderID string) bool {
+	if tenderID == "" {
+		return false
+	}
+
+	// Tender ID should be a non-empty string
+	// You can add more specific validation rules here based on your tender ID format
+	return len(tenderID) > 0 && len(tenderID) <= 100
+}
+
+// IsValidCompanyID validates if the company ID format is correct
+func IsValidCompanyID(companyID string) bool {
+	if companyID == "" {
+		return false
+	}
+
+	// Company ID should be a non-empty string
+	// You can add more specific validation rules here based on your company ID format
+	return len(companyID) > 0 && len(companyID) <= 100
+}
+
+// IsValidSubmissionMode validates if the submission mode is valid
+func IsValidSubmissionMode(mode string) bool {
+	validModes := []string{
+		string(SubmissionModeSelfApply),
+		string(SubmissionModePartnership),
+	}
+
+	for _, validMode := range validModes {
+		if strings.EqualFold(mode, validMode) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// IsValidStatus validates if the approval status is valid
+func IsValidStatus(status string) bool {
+	validStatuses := []string{
+		string(ApprovalStatusApproved),
+		string(ApprovalStatusRejected),
+	}
+
+	for _, validStatus := range validStatuses {
+		if strings.EqualFold(status, validStatus) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// IsValidNotes validates if the notes field is valid
+func IsValidNotes(notes *string) bool {
+	if notes == nil {
+		return true // Notes are optional
+	}
+
+	// Notes should be between 0 and 1000 characters
+	return len(*notes) <= 1000
+}
+
+// IsValidReason validates if the rejection reason is valid
+func IsValidReason(reason string) bool {
+	// Reason should be between 10 and 500 characters
+	if len(reason) < 10 || len(reason) > 500 {
+		return false
+	}
+
+	// Reason should not contain only whitespace
+	if strings.TrimSpace(reason) == "" {
+		return false
+	}
+
+	return true
+}
+
+// IsValidTimestamp validates if the timestamp is within reasonable range
+func IsValidTimestamp(timestamp int64) bool {
+	// Timestamp should be positive and not too far in the future
+	// You can adjust these limits based on your requirements
+	if timestamp <= 0 {
+		return false
+	}
+
+	// Check if timestamp is not too far in the future (e.g., 10 years from now)
+	maxFutureTimestamp := int64(10 * 365 * 24 * 60 * 60) // 10 years in seconds
+	return timestamp <= maxFutureTimestamp
+}
+
+// IsValidLimit validates if the limit parameter is valid
+func IsValidLimit(limit int) bool {
+	return limit > 0 && limit <= 100
+}
+
+// IsValidOffset validates if the offset parameter is valid
+func IsValidOffset(offset int) bool {
+	return offset >= 0
+}
+
+// IsValidSortBy validates if the sort by parameter is valid
+func IsValidSortBy(sortBy string) bool {
+	validSortFields := []string{
+		"created_at",
+		"updated_at",
+		"status",
+		"submission_mode",
+	}
+
+	for _, validField := range validSortFields {
+		if strings.EqualFold(sortBy, validField) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// IsValidSortOrder validates if the sort order parameter is valid
+func IsValidSortOrder(sortOrder string) bool {
+	validOrders := []string{"asc", "desc"}
+
+	for _, validOrder := range validOrders {
+		if strings.EqualFold(sortOrder, validOrder) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// SanitizeString removes potentially dangerous characters from input strings
+func SanitizeString(input string) string {
+	// Remove HTML tags
+	htmlTagRegex := regexp.MustCompile(`<[^>]*>`)
+	sanitized := htmlTagRegex.ReplaceAllString(input, "")
+
+	// Remove script tags
+	scriptRegex := regexp.MustCompile(`(?i)<script[^>]*>.*?</script>`)
+	sanitized = scriptRegex.ReplaceAllString(sanitized, "")
+
+	// Trim whitespace
+	sanitized = strings.TrimSpace(sanitized)
+
+	return sanitized
+}
+
+// ValidateSearchQuery validates if the search query is valid
+func ValidateSearchQuery(query string) bool {
+	if query == "" {
+		return true // Empty query is valid
+	}
+
+	// Query should not be too long
+	if len(query) > 200 {
+		return false
+	}
+
+	// Query should not contain only special characters
+	if regexp.MustCompile(`^[^a-zA-Z0-9\s]+$`).MatchString(query) {
+		return false
+	}
+
+	return true
+}