michael@0: /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: #ifndef nsCharSetProber_h__
michael@0: #define nsCharSetProber_h__
michael@0: 
michael@0: #include "nscore.h"
michael@0: 
michael@0: //#define DEBUG_chardet // Uncomment this for debug dump.
michael@0: 
michael@0: typedef enum {
michael@0:   eDetecting = 0,   //We are still detecting, no sure answer yet, but caller can ask for confidence.
michael@0:   eFoundIt = 1,     //That's a positive answer
michael@0:   eNotMe = 2        //Negative answer
michael@0: } nsProbingState;
michael@0: 
michael@0: #define SHORTCUT_THRESHOLD      (float)0.95
michael@0: 
michael@0: class nsCharSetProber {
michael@0: public:
michael@0:   virtual ~nsCharSetProber() {}
michael@0:   virtual const char* GetCharSetName() = 0;
michael@0:   virtual nsProbingState HandleData(const char* aBuf, uint32_t aLen) = 0;
michael@0:   virtual nsProbingState GetState(void) = 0;
michael@0:   virtual void      Reset(void)  = 0;
michael@0:   virtual float     GetConfidence(void) = 0;
michael@0: 
michael@0: #ifdef DEBUG_chardet
michael@0:   virtual void  DumpStatus() {};
michael@0: #endif
michael@0: 
michael@0:   // Helper functions used in the Latin1 and Group probers.
michael@0:   // both functions Allocate a new buffer for newBuf. This buffer should be 
michael@0:   // freed by the caller using PR_FREEIF.
michael@0:   // Both functions return false in case of memory allocation failure.
michael@0:   static bool FilterWithoutEnglishLetters(const char* aBuf, uint32_t aLen, char** newBuf, uint32_t& newLen);
michael@0:   static bool FilterWithEnglishLetters(const char* aBuf, uint32_t aLen, char** newBuf, uint32_t& newLen);
michael@0: 
michael@0: };
michael@0: 
michael@0: #endif /* nsCharSetProber_h__ */