/* vi: set sw=4 ts=4: */
/*
 * CCE - Console Chinese Environment -
 * Copyright (C) 1998-2003 Rui He (rhe@3eti.com)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include 	<stdio.h>
#include 	<unistd.h>
#include 	<stdlib.h>
#include 	<stdarg.h>
#include	<errno.h>
#include	<string.h>
#include	<sys/types.h>
#include 	<time.h>

#include 	<defs.h>
#include 	<vc.h>
#include 	<hzinput.h>
#include 	<pinyin.h>
#include 	<errors.h>

#define SUPPORT_ASSOCIATE

#define MAX_ASSOCIATE_CANDIATES 8 /* 10 */

#ifdef SUPPORT_ASSOCIATE

static unsigned char LastOutputChar[2];   
 
int LoadAssociateFile(hz_input_table *table, const char *filename)
{
	AssociateHeader AscHeader;
	char fname[CCE_PATHNAME_MAX+1];

	if (!table) return -1;
	if (!(table->AssocFile = fopen( filename, R_CNTRL)))
	{
		strcpy(fname, CCELIB "/");
		if (strlen(fname) + strlen(filename) >= CCE_PATHNAME_MAX) return -1; /* buffer overrun */
		strcat(fname, filename);
		table->AssocFile = fopen( fname, R_CNTRL);
	}

	if (table->AssocFile == NULL || fread(&AscHeader, sizeof(AscHeader), 1, table->AssocFile) != 1 ||
		strcmp(ASSOCIATE_MAGIC_NUMBER, AscHeader.MagicNum) )
 	{
     	warn("Load Assoc File %s error!\n", filename);
		if (table->AssocFile) fclose(table->AssocFile);
		table->AssocFile = NULL;
	 	return -1;
 	}

	{
		table->AscEncoding = AscHeader.Encoding; /* for calculating index */
		table->AscMinIndex = AscHeader.MinIndex;
		table->AscMaxIndex = AscHeader.MaxIndex;
		table->AscPhraseOffset = AscHeader.PhraseOffset;

		return 0;
	}

    warn("Assoc File %s is using an incompatible encoding with the input method!\n", filename);
    fclose(table->AssocFile);
    table->AssocFile = NULL;
    return -1;
}

int FindAssociateKeyAndFill(unsigned char LastChar[])
{
    int ofs[2], index;
  	unsigned char myLastChar[2]; /* in AscEncoding  */
	
	LastOutputChar[0] = LastChar[0];
	LastOutputChar[1] = LastChar[1]; /* save it */

	if (!cur_table->AssocFile) return 0; 
	
	if ( ConvertEncoding_Char(lInfo.sysCoding, cur_table->AscEncoding, LastChar[0], LastChar[1],
               myLastChar, myLastChar+1) == -1) /* failed to convert */
		return 0; 
	
	index = CalculateCharIndex(cur_table->AscEncoding, myLastChar[0], myLastChar[1]);
	if (index < cur_table->AscMinIndex || index >= cur_table->AscMaxIndex) /* not within valid range */
		return 0;

	index -= cur_table->AscMinIndex;
    if (fseek(cur_table->AssocFile, index * sizeof(int) + sizeof(AssociateHeader), SEEK_SET) ||
    	fread(ofs, sizeof(int), 2, cur_table->AssocFile) != 2) 
		return 0;   /* some error */

    StartIndex = ofs[0] + cur_table->AscPhraseOffset;
    EndIndex = ofs[1] + cur_table->AscPhraseOffset;

	CurrentPageIndex = StartIndex; /* update the current page pointer */

	FillAssociateChars(StartIndex);

	if (CurSelNum > 0)
	{
		IsDirectSelect = 0; /* !cur_table->FirstInputSelectKeyConflict; */

		IsAssociateMode = 1;

		DisplayAssociateInput(); 
        DisplaySelection(); /* using the SelTab */
	}

	return CurSelNum;
}

int FillAssociateChars(int index)
{
	unsigned char str[MAX_PHRASE_LENGTH+1];
    int i, CurLen = 0, len = 0, converted;
   
	if (index < StartIndex) index = StartIndex;
	if (StartIndex == index) CurrentPage = 0;
	if (CurrentPage < MAX_PAGE_INDEX) SavedPageIndex[CurrentPage] = index;

    for(CurSelNum = 0;  CurSelNum < /*cur_table->MaxDupSel*/ MAX_ASSOCIATE_CANDIATES &&
			index < EndIndex && CurLen < cur_table->SelAreaWidth-3; index += len+1)
    {  /* -2 for < > */
		if (fseek( cur_table->AssocFile, index, SEEK_SET ) ||
            fread( str, 1, sizeof(str), cur_table->AssocFile ) < 2) 
			break;  /* error occurs */

		str[MAX_PHRASE_LENGTH] = '\0';  /* for safety reason */
		len = strlen(str);
		if (len & 1) len--;
		
		converted = 1;
		for(i = 0; i < len; i += 2)
		{
			if (ConvertEncoding_Char(cur_table->AscEncoding, lInfo.sysCoding, str[i], str[i+1],
						str+i, str+i+1) == -1)
			{
				converted = 0;
				break;
			}
		}
		if (converted) /* success */
		{
       		strncpy(SelTab[CurSelNum],str, len);
			SelTab[CurSelNum++][len] = '\0'; /* terminate */
       		CurLen += len + 2;  /* we plus 2 for SELECT KEY and SPACE after it */
		}
	}

	if (CurSelNum == 0) return 0; /* no match found */
	
    if ( index < EndIndex /* && CurSelNum == cur_table->MaxDupSel */ )
    {

        NextPageIndex = index;
        MultiPageMode = 1;
    }
    else if (MultiPageMode)
    {
        NextPageIndex = StartIndex; /* rotate selection */
    }

	return CurSelNum;
}

void DisplayAssociateInput(void)
{
	int n;
	char buf[MAX_INPUT_LENGTH];
	int StartPos = cur_table->InputAreaX;
    int EndPos = cur_table->InputAreaWidth + cur_table->InputAreaX;

	if (cur_table->InputType == INPUT_TYPE_INTCODE) 
		n = snprintf(buf, sizeof(buf), "%c%c:", LastOutputChar[0], LastOutputChar[1]);
	else
		n = snprintf(buf, sizeof(buf), "  %s    %c%c:", LianXiangStr[(int)lInfo.sysCoding 
], LastOutputChar[0], LastOutputChar[1]);
	InputAreaOutput(lInfo.sysCoding /* cur_table->AscEncoding */, StartPos, buf, 
				INPUT_FGCOLOR,INPUT_BGCOLOR);
	StartPos += n;
	while(StartPos < EndPos)
		pVideoInfo->input_sput(StartPos++, ' ', INPUT_FGCOLOR,INPUT_BGCOLOR); /* output a space */
}

int Associate_HZFilter(int tty_fd, unsigned char key)
{
  	int SelKeyIndex;
	char *SelKeyStr;
    char *is_sel_key = (char*)0;

	if (CurSelNum <= 0) return 0; /* we have no candidates? we don't handle it it's for safety reason only */

    SelKeyStr = ( IsDirectSelect ? cur_table->selkey : cur_table->Shift_SelKey);
    if ((is_sel_key = strchr( SelKeyStr, key)))  /* not NULL, we fount it */
    {

        SelKeyIndex = is_sel_key - SelKeyStr;

        if (SelKeyIndex < CurSelNum && SelTab[SelKeyIndex][0])
        {
            OutputSelection(lInfo.sysCoding, tty_fd, SelTab[SelKeyIndex]);
            return 1;  /* if In DirectSelect and it's a valid select key, output and return */
        }
    }

	if (MultiPageMode)
	{
		if (index(/*cur_table->pageprevkey*/ ASSOCIATE_PAGEPREV_KEYS , key))
		{
			if (CurrentPage != 0)
        	{
				if (--CurrentPage < MAX_PAGE_INDEX)
					CurrentPageIndex = SavedPageIndex[CurrentPage];
				else	/* These index are file offsets, pointing to strings ending with 0, so at least 3*10 */
        			CurrentPageIndex -= 3 * MAX_ASSOCIATE_CANDIATES; /* 2 bytes(1 Chinese char) + 1 '\0' */
				FillAssociateChars(CurrentPageIndex);
				DisplaySelection();
				return 1;  /* we handled it and stay in AssociateMode */
        	}
		}
		else if (index(/*cur_table->pagenextkey*/ ASSOCIATE_PAGENEXT_KEYS , key) && CurSelNum > 0
                )
		{
			if (NextPageIndex <= CurrentPageIndex) /* last page, need to rorate */
				CurrentPage = 0;
			else CurrentPage++;
			
           	CurrentPageIndex = NextPageIndex;
		    FillAssociateChars(CurrentPageIndex);
			DisplaySelection();
			return 1;   /* we handled it and stay in AssociateMode */
        }
	}

#if 0
	switch ( key )
	{
    case '\010':  /* BackSpace Ctrl+H */
    case '\177':  /* BackSpace */
	case '\033':  /* ESCAPE */
		break;

	case ' ':
		if ( SelTab[0][0] ) /* output first item */
		{
        	OutputSelection(lInfo.sysCoding, tty_fd, SelTab[0]);
			return 1;  /* we handled it and no need to reset */
		}
        break;

     default: /* we don't handle any other keys */
		break;
	} 
#endif

	ResetInput(1,1);  /* clear everything IsAssociateMode will be set to 0 */
	return 0;  /* we didn't handle it */
}

#endif