/*
  Name:             appint
  Copyright:        Copyright (C) SIL International.
  Documentation:
  Description:
  Create Date:      5 Nov 2007

  Modified Date:    23 Jun 2014
  Authors:          mcdurdin
  Related Files:
  Dependencies:

  Bugs:
  Todo:
  Notes:
  History:          05 Nov 2007 - mcdurdin - I1129 - Fix irregular behaviour with context rules in debugger
                    27 Jan 2009 - mcdurdin - I1797 - Add fallback for AIWin2000 app integration
                    11 Dec 2009 - mcdurdin - I934 - x64 - Initial version
                    12 Mar 2010 - mcdurdin - I934 - x64 - Complete
                    12 Mar 2010 - mcdurdin - I2229 - Remove hints and warnings
                    03 Oct 2011 - mcdurdin - I3091 - IMX DLLs cause an assertion failure due to buffer size mismatch
                    17 Nov 2012 - mcdurdin - I3575 - V9.0 - context must be cached for legacy mode in TSF as rules are processed twice
                    10 Jun 2014 - mcdurdin - I4262 - V9.0 - TSF deadkeys do not function correctly
                    23 Jun 2014 - mcdurdin - I4287 - V9.0 - Remove extraneous AppIntegration class type tests
*/
   // I4287
#include "pch.h"

PWSTR decxstr(PWSTR p, PWSTR pStart);

const LPSTR ItemTypes[8] = {
	"QIT_VKEYDOWN", "QIT_VKEYUP", "QIT_VSHIFTDOWN", "QIT_VSHIFTUP",
    "QIT_CHAR", "QIT_DEADKEY", "QIT_BELL", "QIT_BACK" };

/* AppContext */

AppContext::AppContext()
{
	Reset();
}

void AppContext::Add(WCHAR ch)
{
	if(pos == MAXCONTEXT - 1)
	{
//    SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext: MAXCONTEXT[%d]: %ws", pos, CurContext);
		memmove(CurContext, &CurContext[1], MAXCONTEXT*2 - 2); pos--;
	}

	CurContext[pos++] = ch;
	CurContext[pos] = 0;

  SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext: Add(%x) [%d]: %s", ch, pos, Debug_UnicodeString(CurContext));
}

WCHAR *AppContext::Buf(int n)
{
	WCHAR *p;

	//SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext::Buf(%d)", n);
	//if(n == 0) return wcschr(CurContext, 0);
	//if(*CurContext == 0) return NULL;

	for(p = wcschr(CurContext, 0); n > 0 && p > CurContext; p = decxstr(p, CurContext), n--);
	//for(p = wcschr(CurContext, 0); n > 0 && p > CurContext; p--, n--);

	if(n > 0) return NULL;
	return p;
}

WCHAR *AppContext::BufMax(int n)  // Used only by IMX DLLs
{
	WCHAR *p = wcschr(CurContext, 0);  // I3091

	if(CurContext == p || n == 0) return p; /* empty context or 0 characters requested, return pointer to end of context */  // I3091

  WCHAR *q = p;  // I3091
	for(; p > CurContext && (INT_PTR)(q-p) < n; p = decxstr(p, CurContext));  // I3091

  if((INT_PTR)(q-p) > n) p = incxstr(p); /* Copes with deadkey or supplementary pair at start of returned buffer making it too long */  // I3091

  return p;  // I3091
}

void AppContext::Delete()
{
  if (CharIsDeadkey()) {
    pos -= 2;
  } else if (CharIsSurrogatePair()) {
    pos--;
  }
	//SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext::Delete");

	if(pos > 0) pos--;
	CurContext[pos] = 0;
	//if(--pos < 0) pos = 0;
	//SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext: Delete");
}

void AppContext::Reset()
{
	pos = 0;
	CurContext[0] = 0;

//	SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext: Reset");
}

void AppContext::Get(WCHAR *buf, int bufsize)
{
	for(WCHAR *p = CurContext; *p && bufsize > 0; p++, bufsize--)
	{
		*buf = *p; buf++;
		if(*p >= 0xD800 && *p <= 0xDBFF) { *buf = *(++p); bufsize--; buf++; }
	}
	//wcsncpy(buf, CurContext, bufsize);
	*buf = 0;
	//buf[bufsize-1] = 0;
}

void AppContext::CopyFrom(AppContext *source)   // I3575
{
  SendDebugMessageFormat(0, sdmAIDefault, 0, "AppContext::CopyFrom source=%s; before copy, dest=%s", Debug_UnicodeString(source->CurContext, 0), Debug_UnicodeString(CurContext, 1));
  wcscpy_s(CurContext, _countof(CurContext), source->CurContext);
	pos = source->pos;
}


void AppContext::Set(const WCHAR *buf)
{
	const WCHAR *p;
	WCHAR *q;
	for(p = buf, q = CurContext; *p && (INT_PTR)(q-CurContext) < MAXCONTEXT - 1; p++, q++)
	{
		*q = *p;
		if(*p >= 0xD800 && *p <= 0xDBFF) { *(++q) = *(++p); }
	}
	*q = 0;
  pos = (int)(INT_PTR)(q-CurContext);  // I1129 - Irregular behaviour with context rules
	CurContext[MAXCONTEXT-1] = 0;
}

BOOL AppContext::CharIsDeadkey()
{
	if(pos < 3) // code_sentinel, deadkey, #, 0
		return FALSE;
	return CurContext[pos-3] == UC_SENTINEL &&
		   CurContext[pos-2] == CODE_DEADKEY;
}

BOOL AppContext::CharIsSurrogatePair()
{
  if (pos < 2) // low_surrogate, high_surrogate
    return FALSE;

  return Uni_IsSurrogate1(CurContext[pos - 2]) &&
    Uni_IsSurrogate2(CurContext[pos - 1]);
}

/* AppActionQueue */

AppActionQueue::AppActionQueue()
{
  memset(Queue, 0, sizeof(APPACTIONQUEUEITEM) * MAXACTIONQUEUE);
	ResetQueue();
}

void AppActionQueue::ResetQueue()
{
	//SendDebugMessageFormat(0, sdmAIDefault, 0, "App::ResetQueue");
	QueueSize = 0;   // I4262
}

BOOL AppActionQueue::QueueAction(int ItemType, DWORD dwData)
{
	if(QueueSize > MAXACTIONQUEUE - 1)
	{
		MessageBeep(0xFFFFFFFF);
		return FALSE;
	}

	Queue[QueueSize].ItemType = ItemType;
	Queue[QueueSize].dwData   = dwData;

	QueueSize++;

	SendDebugMessageFormat(0, sdmAIDefault, 0, "App::QueueAction: %s %x", ItemTypes[ItemType], dwData);

	return TRUE;
}

/* AppIntegration */

AppIntegration::AppIntegration()
{
	hwnd = NULL;
  FShiftFlags = 0;
}