feat: backend core - auth, user, role, permission, device, webhook, monitoring, cache, repository, service, middleware, API handlers

internal/pkg/pagination/pagination.go

@@ -0,0 +1,43 @@
+// Package pagination provides types and helpers for paginated responses.
+package pagination
+
+// PaginationParams 分页参数
+type PaginationParams struct {
+	Page     int
+	PageSize int
+}
+
+// PaginationResult 分页结果
+type PaginationResult struct {
+	Total    int64
+	Page     int
+	PageSize int
+	Pages    int
+}
+
+// DefaultPagination 默认分页参数
+func DefaultPagination() PaginationParams {
+	return PaginationParams{
+		Page:     1,
+		PageSize: 20,
+	}
+}
+
+// Offset 计算偏移量
+func (p PaginationParams) Offset() int {
+	if p.Page < 1 {
+		p.Page = 1
+	}
+	return (p.Page - 1) * p.PageSize
+}
+
+// Limit 获取限制数
+func (p PaginationParams) Limit() int {
+	if p.PageSize < 1 {
+		return 20
+	}
+	if p.PageSize > 100 {
+		return 100
+	}
+	return p.PageSize
+}