tell application "BBEdit"

    set theData to contents of text window 1

    set theNewContents to my urlEncode(theData)

    set contents of text window 1 to theNewContents

end tell



on urlUnEncode(theString)

    local theResult, theCharacters, theReplacements, tempString

    set theResult to ""

    set tempString to ""

    set theReplacements to {" ", "&", "\"", "'", tab, return, "(", ")", "@"}

    set theCharacters to {"%20", "%26", "%22", "%27", "%09", "%0d", "%28", "%29", "%40"}

    

    repeat with i from 1 to count of theCharacters

        set tempString to my breakStringAtCharacter(theString, item i of theCharacters)

        set AppleScript's text item delimiters to (item i of theReplacements)

        set theString to every item of tempString as string

    end repeat

    

    set theResult to theString

    

    return theResult

end urlUnEncode