问需要帮助识别这段代码到底做了什么(我有一个大致的想法)

EN

let $removeLastCR:=fn:replace($output.output_FileContent , '(\r?\n|\r)$', '')
let $lines := tokenize($removeLastCR, '\n')
return

for $line at $counter in $lines
let $x := 
    for $i in fn:tokenize($line,'"')
    return 
        if(fn:starts-with($i,',') and fn:ends-with($i,','))
            then fn:substring($i,2,fn:string-length($i)-2)
        else 
            if(fn:starts-with($i,','))
                then fn:substring-after($i,',')
            else 
                if(fn:ends-with($i,','))
                    then fn:substring($i,1,fn:string-length($i)-1)
                else $i
let $fields :=
    for $j at $k in $x
    return 
    if(fn:starts-with($line,'"'))
        then 
            if($k mod 2 = 0)
                then fn:tokenize($j,',')
            else $j
    else 
        if($k mod 2 = 0)
            then $j
        else fn:tokenize($j,',')
return