package response

import (
	"net/http"
	"time"
)

// Response 统一响应结构
type Response struct {
	Success bool        `json:"success"`
	Code    int         `json:"code"`
	Message string      `json:"message"`
	Data    interface{} `json:"data,omitempty"`
	Meta    *Meta       `json:"meta,omitempty"`
}

// Meta 元数据
type Meta struct {
	Timestamp string `json:"timestamp"`
	RequestID string `json:"request_id,omitempty"`
}

// PaginatedResponse 分页响应
type PaginatedResponse struct {
	Success    bool        `json:"success"`
	Code       int         `json:"code"`
	Message    string      `json:"message"`
	Data       interface{} `json:"data"`
	Pagination *Pagination `json:"pagination"`
	Meta       *Meta       `json:"meta,omitempty"`
}

// Pagination 分页信息
type Pagination struct {
	Page       int   `json:"page"`
	Limit      int   `json:"limit"`
	Total      int64 `json:"total"`
	TotalPages int   `json:"total_pages"`
	HasNext    bool  `json:"has_next"`
	HasPrev    bool  `json:"has_prev"`
}

// Success 成功响应
func Success(data interface{}) *Response {
	return &Response{
		Success: true,
		Code:    http.StatusOK,
		Message: "Success",
		Data:    data,
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// Error 错误响应
func Error(code int, message string) *Response {
	return &Response{
		Success: false,
		Code:    code,
		Message: message,
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// Created 创建成功响应
func Created(data interface{}) *Response {
	return &Response{
		Success: true,
		Code:    http.StatusCreated,
		Message: "Created successfully",
		Data:    data,
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// Updated 更新成功响应
func Updated(data interface{}) *Response {
	return &Response{
		Success: true,
		Code:    http.StatusOK,
		Message: "Updated successfully",
		Data:    data,
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// Deleted 删除成功响应
func Deleted() *Response {
	return &Response{
		Success: true,
		Code:    http.StatusOK,
		Message: "Deleted successfully",
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// Paginated 分页响应
func Paginated(data interface{}, page, limit int, total int64) *PaginatedResponse {
	totalPages := int((total + int64(limit) - 1) / int64(limit))
	
	return &PaginatedResponse{
		Success: true,
		Code:    http.StatusOK,
		Message: "Success",
		Data:    data,
		Pagination: &Pagination{
			Page:       page,
			Limit:      limit,
			Total:      total,
			TotalPages: totalPages,
			HasNext:    page < totalPages,
			HasPrev:    page > 1,
		},
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}

// BadRequest 400错误
func BadRequest(message string) *Response {
	return Error(http.StatusBadRequest, message)
}

// Unauthorized 401错误
func Unauthorized(message string) *Response {
	return Error(http.StatusUnauthorized, message)
}

// Forbidden 403错误
func Forbidden(message string) *Response {
	return Error(http.StatusForbidden, message)
}

// NotFound 404错误
func NotFound(message string) *Response {
	return Error(http.StatusNotFound, message)
}

// InternalServerError 500错误
func InternalServerError(message string) *Response {
	return Error(http.StatusInternalServerError, message)
}

// ValidationError 验证错误
func ValidationError(errors map[string]string) *Response {
	return &Response{
		Success: false,
		Code:    http.StatusUnprocessableEntity,
		Message: "Validation failed",
		Data:    errors,
		Meta: &Meta{
			Timestamp: time.Now().Format(time.RFC3339),
		},
	}
}