You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: casual_time.go
    path of file: ./repos/when/rules/zh
    
    the code of the file until where you have to start completion: package zh

import (
	"regexp"
	"strings"
	"time"

	"github.com/AlekSi/pointer"
	"github.com/olebedev/when/rules"
)

func CasualTime(s rules.Strategy) rules.Rule {
	overwrite := s == rules.Override

	return &rules.F{
		RegExp: regexp.MustCompile(`(?i)(?:\W|^)((今天)?\s*(早晨|下午|傍晚|中午|晚上))`),
		Applier: func(m *rules.Match, c *rules.Context, o *rules.Options, ref time.Time) (bool, error) {

			lower := strings.ToLower(strings.TrimSpace(m.String()))

			if (c.Hour != nil || c.Minute != nil) && !overwrite {
				return false, nil
			}

			switch {
			case strings.Contains(lower, "晚上"):
				if o.Evening != 0 {
					c.Hour = &o.Evening
				} else {
					c.Hour = poin
    
func CasualTime(s rules.Strategy) rules.Rule {
	overwrite := s == rules.Override

	return &rules.F{
		RegExp: regexp.MustCompile(`(?i)(?:\W|^)((今天)?\s*(早晨|下午|傍晚|中午|晚上))`),
		Applier: func(m *rules.Match, c *rules.Context, o *rules.Options, ref time.Time) (bool, error) {

			lower := strings.ToLower(strings.TrimSpace(m.String()))

			if (c.Hour != nil || c.Minute != nil) && !overwrite {
				return false, nil
			}

			switch {
			case strings.Contains(lower, "晚上"):
				if o.Evening != 0 {
					c.Hour = &o.Evening
				} else {
					c.Hour = pointer.ToInt(20)
				}
				c.Minute = pointer.ToInt(0)
			case strings.Contains(lower, "下午"):
				if o.Afternoon != 0 {
					c.Hour = &o.Afternoon
				} else {
					c.Hour = pointer.ToInt(15)
				}
				c.Minute = pointer.ToInt(0)
			case strings.Contains(lower, "傍晚"):
				if o.Evening != 0 {
					c.Hour = &o.Evening
				} else {
					c.Hour = pointer.ToInt(18)
				}
				c.Minute = pointer.ToInt(0)
			case strings.Contains(lower, "早晨"):
				if o.Morning != 0 {
					c.Hour = &o.Morning
				} else {
					c.Hour = pointer.ToInt(8)
				}
				c.Minute = pointer.ToInt(0)
			case strings.Contains(lower, "中午"):
				if o.Noon != 0 {
					c.Hour = &o.Noon
				} else {
					c.Hour = pointer.ToInt(12)
				}
				c.Minute = pointer.ToInt(0)
			}

			return true, nil
		},
	}
}