capture program drop paper
program define paper

version 14

syntax [anything(name = class)]  
qui{   
preserve 
    if "`class'"==""{ 
        local class: disp %dCYND date("`c(current_date)'","DMY")
        
    }
    
    else{
        if length("`class'")!=4 {
            disp as error `"`class'不是有效的日期"'
            exit 601
        }     
        local class="2021"+"`class'"
    }

        local year  = substr("`class'",1,4)
        local month = substr("`class'",5,2)
        local day   = substr("`class'",7,2)
        
        local URL "http://paper.people.com.cn/rmrb/html/`year'-`month'/`day'/nbs.D110000renmrb_01.htm"
        tempfile  html_text   
        cap copy `"`URL'"' "`html_text'.txt", replace  
		if _rc ~= 0 {
			di as err "`month'月`day'日不是有效的日期 或者 `month'月`day'日报纸还没更新"
			exit 601
		}
        infix strL v 1-10000 using "`html_text'.txt", clear 
        
        keep if index(v, "id=pageLink")
        split v, p(`"htm>"'  "版"   "："   "</a>")
        gen url="http://paper.people.com.cn/rmrb/images/"+"`year'"+"-"+"`month'"+"/"+"`day'"+"/"+v2+"/"+"rmrb"+"`class'"+v2+".pdf"
        gen paper= url + "++"+v2+"版：" +v4+ ".pdf" 
        keep paper
        rename paper v
        qui split v,  p("++")      		
		rename  v1  link                   
        rename  v2  title               
        local n=_N
 }   
    dis _col(3) as red "《人民日报》2021年`month'月`day'日" 
	forvalues i = 1/`n' {         
		local link  =   link[`i']
		local title =   title[`i']
		dis _col(8) `"{browse "`link'": `title'}"'													
	}
restore    
 
end