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 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is 
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 * the Initial Developer. All Rights Reserved.
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 * Contributor(s):
 *
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 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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#include "nsSemanticUnitScanner.h"
#include "prmem.h"

NS_IMPL_ISUPPORTS1(nsSemanticUnitScanner, nsISemanticUnitScanner)

nsSemanticUnitScanner::nsSemanticUnitScanner() : nsSampleWordBreaker()
{
  /* member initializers and constructor code */
}

nsSemanticUnitScanner::~nsSemanticUnitScanner()
{
  /* destructor code */
}


/* void start (in string characterSet); */
NS_IMETHODIMP nsSemanticUnitScanner::Start(const char *characterSet)
{
    // do nothing for now.
    return NS_OK;
}

/* void next (in wstring text, in long length, in long pos, out boolean hasMoreUnits, out long begin, out long end); */
NS_IMETHODIMP nsSemanticUnitScanner::Next(const PRUnichar *text, PRInt32 length, PRInt32 pos, PRBool isLastBuffer, PRInt32 *begin, PRInt32 *end, PRBool *_retval)
{
    // xxx need to bullet proff and check input pointer 
    //  make sure begin, end and _retval is not nsnull here

    // if we reach the end, just return
    if (pos >= length) {
       *begin = pos;
       *end = pos;
       *_retval = PR_FALSE;
       return NS_OK;
    }

    PRUint8 char_class = nsSampleWordBreaker::GetClass(text[pos]);

    // if we are in chinese mode, return one han letter at a time
    // we should not do this if we are in Japanese or Korean mode
    if (kWbClassHanLetter == char_class) {
       *begin = pos;
       *end = pos+1;
       *_retval = PR_TRUE;
       return NS_OK;
    }

    PRUint32 next;
    PRBool needMoreText;
    // find the next "word"
    nsresult res = NextWord(text, (PRUint32) length, (PRUint32) pos, 
        &next, &needMoreText);

    NS_ASSERTION(NS_SUCCEEDED(res), "nsSampleWordBreaker::Next failed");
    if (NS_FAILED(res)) 
        return res;

    // if we don't have enough text to make decision, return 
    if (needMoreText) {
       *begin = pos;
       *end = isLastBuffer ? length : pos;
       *_retval = isLastBuffer;
       return NS_OK;
    } 
    
    // if what we got is space or punct, look at the next break
    if ((char_class == kWbClassSpace) || (char_class == kWbClassPunct)) {
        // if the next "word" is not letters, 
        // call itself recursively with the new pos
        return Next(text, length, next, isLastBuffer, begin, end, _retval);
    }

    // for the rest, return 
    *begin = pos;
    *end = next;
    *_retval = PR_TRUE;
    return NS_OK;
}

