// -*- coding:unix; mode:c++; tab-width:4; c-basic-offset:4; indent-tabs-mode:nil -*-
/* Unikey Vietnamese Input Method
 * Copyright (C) 2000-2005 Pham Kim Long
 * Contact:
 *   unikey@gmail.com
 *   UniKey project: http://unikey.org
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor
 * Boston, MA 02110-1301, USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iostream>
#include "mactab.h"
#include "vnconv.h"

using namespace std;
#define UKMACRO_VERSION_UTF8 1

//---------------------------------------------------------------
void CMacroTable::init()
{
  m_memSize = MACRO_MEM_SIZE;
  m_count = 0;
  m_occupied = 0;
}

//---------------------------------------------------------------
char *MacCompareStartMem;

#define STD_TO_LOWER(x) (((x) >= VnStdCharOffset && \
                          (x) < (VnStdCharOffset + TOTAL_ALPHA_VNCHARS) && \
                          !((x) & 1)) ? \
                          (x+1) : (x))

int macCompare(const void *p1, const void *p2)
{
    StdVnChar *s1 = (StdVnChar *) ((char *)MacCompareStartMem + ((MacroDef *)p1)->keyOffset);
    StdVnChar *s2 = (StdVnChar *) ((char *)MacCompareStartMem + ((MacroDef *)p2)->keyOffset);

    int i;
    StdVnChar ls1, ls2;

    for (i=0; s1[i] != 0 && s2[i] != 0; i++) {
        ls1 = STD_TO_LOWER(s1[i]);
        ls2 = STD_TO_LOWER(s2[i]);
        if (ls1 > ls2)
            return 1;
        if (ls1 < ls2)
            return -1;
        /*
        if (s1[i] > s2[i])
            return 1;
        if (s1[i] < s2[i])
            return -1;
        */
    }
    if (s1[i] == 0)
        return (s2[i] == 0)? 0 : -1;
    return 1;
}

//---------------------------------------------------------------
int macKeyCompare(const void *key, const void *ele)
{
    StdVnChar *s1 = (StdVnChar *)key;
    StdVnChar *s2 = (StdVnChar *) ((char *)MacCompareStartMem + ((MacroDef *)ele)->keyOffset);

    StdVnChar ls1, ls2;
    int i;
    for (i=0; s1[i] != 0 && s2[i] != 0; i++) {
        ls1 = STD_TO_LOWER(s1[i]);
        ls2 = STD_TO_LOWER(s2[i]);
        if (ls1 > ls2)
            return 1;
        if (ls1 < ls2)
            return -1;
        /*
        if (s1[i] > s2[i])
            return 1;
        if (s1[i] < s2[i])
            return -1;
        */
    }
    if (s1[i] == 0)
        return (s2[i] == 0)? 0 : -1;
    return 1;
}

//---------------------------------------------------------------
const StdVnChar *CMacroTable::lookup(StdVnChar *key)
{
  MacCompareStartMem = m_macroMem;
  MacroDef *p = (MacroDef *)bsearch(key, m_table, m_count, sizeof(MacroDef), macKeyCompare);
  if (p)
    return (StdVnChar *)(m_macroMem + p->textOffset);
  return 0;
}

//----------------------------------------------------------------------------
// Read header, if it's present in the file. Get the version of the file
// If header is absent, go back to the beginning of file and set version to 0
// Return false if reading failed.
//
// Header format: ;[DO NOT DELETE THIS LINE]***version=n
//----------------------------------------------------------------------------
bool CMacroTable::readHeader(FILE *f, int & version)
{
    char line[MAX_MACRO_LINE];
    if (!fgets(line, sizeof(line), f)) {
        if (feof(f)) {
            fseek(f, 0, SEEK_SET);
            version = 0;
            return true;
        }
        return false;
    }

    //if BOM is available, skip it
    char *p = line;
    size_t len = strlen(line);
    if (len >= 3 && (unsigned char)line[0] == 0xEF && (unsigned char)line[1] == 0xBB &&
                    (unsigned char)line[2] == 0xBF)
    {
        p += 3;
    }

    //read version number
    p = strstr(p, "***");
    if (p) {
        p += 3;
        //skip possible spaces
        while (*p == ' ') p++;
        if (sscanf(p, "version=%d", &version) == 1)
            return true;
    }

    fseek(f, 0, SEEK_SET);
    version = 0;
    return true;
}

//----------------------------------------------------------------
void CMacroTable::writeHeader(FILE *f)
{
#if defined(WIN32)
    fprintf(f, "\xEF\xBB\xBF;DO NOT DELETE THIS LINE*** version=%d ***\n", UKMACRO_VERSION_UTF8);
#else
    fprintf(f, "DO NOT DELETE THIS LINE*** version=%d ***\n", UKMACRO_VERSION_UTF8);
#endif
}
//---------------------------------------------------------------
int CMacroTable::loadFromFile(const char *fname)
{
    FILE *f;
#if defined(WIN32)
    f = _tfopen(fname, _TEXT("rt"));
#else
    f = fopen(fname, "r");
#endif

    if (f == NULL)
        return 0;
    char line[MAX_MACRO_LINE];
    size_t len;

    resetContent();

    //read possible header
    int version;
    if (!readHeader(f, version)) {
        version = 0;
    }

    while (fgets(line, sizeof(line), f)) {
        len = strlen(line);
        if (len > 0 && line[len-1] == '\n')
            line[len-1] = 0;
        if (len > 1 && line[len-2] == '\r')
            line[len-2] = 0;
        if (version == UKMACRO_VERSION_UTF8)
            addItem(line, CONV_CHARSET_UNIUTF8);
        else
            addItem(line, CONV_CHARSET_VIQR);
    }
    fclose(f);
    MacCompareStartMem = m_macroMem;
    qsort(m_table, m_count, sizeof(MacroDef), macCompare);
    // Convert old version
    if (version != UKMACRO_VERSION_UTF8) {
        writeToFile(fname);
    }
    return 1;
}

//---------------------------------------------------------------
int CMacroTable::writeToFile(const char *fname)
{
  FILE *f;
#if defined(WIN32)
  f = _tfopen(fname, _TEXT("wt"));
#else
  f = fopen(fname, "w");
#endif
  return writeToFp(f);
}

int CMacroTable::writeToFp(FILE* f)
{
  int ret;
  int inLen, maxOutLen;

  if (f == NULL)
    return 0;

  char line[MAX_MACRO_LINE*3]; //1 VnChar may need 3 chars in UTF8
  char key[MAX_MACRO_KEY_LEN*3];
  char text[MAX_MACRO_TEXT_LEN*3];

  writeHeader(f);

  UKBYTE *p;
  for (int i=0; i < m_count; i++) {
    p = (UKBYTE *)m_macroMem + m_table[i].keyOffset;
    inLen = -1;
    maxOutLen = sizeof(key);
    ret = VnConvert(CONV_CHARSET_VNSTANDARD, CONV_CHARSET_UNIUTF8,
		    (UKBYTE *) p, (UKBYTE *)key,
		    &inLen, &maxOutLen);
    if (ret != 0)
      continue;

    p = (UKBYTE *)m_macroMem + m_table[i].textOffset;
    inLen = -1;
    maxOutLen = sizeof(text);
    ret = VnConvert(CONV_CHARSET_VNSTANDARD, CONV_CHARSET_UNIUTF8,
		    p, (UKBYTE *)text,
		    &inLen, &maxOutLen);
    if (ret != 0)
      continue;
    if (i < m_count-1)
      sprintf(line, "%s:%s\n", key, text);
    else
      sprintf(line, "%s:%s", key, text);
    fputs(line, f);
  }

  fclose(f);
  return 1;
}

//---------------------------------------------------------------
int CMacroTable::addItem(const void *key, const void *text, int charset)
{
  int ret;
  int inLen, maxOutLen;
  int offset = m_occupied;
  char *p = m_macroMem + offset;

  if (m_count >= MAX_MACRO_ITEMS)
    return -1;

  m_table[m_count].keyOffset = offset;

  // Convert macro key to VN standard
  inLen = -1; //input is null-terminated
  maxOutLen = MAX_MACRO_KEY_LEN * sizeof(StdVnChar);
  if (maxOutLen + offset > m_memSize)
    maxOutLen = m_memSize - offset;
  ret = VnConvert(charset, CONV_CHARSET_VNSTANDARD,
		          (UKBYTE *)key, (UKBYTE *)p,
		          &inLen, &maxOutLen);
  if (ret != 0)
    return -1;

  offset += maxOutLen;
  p += maxOutLen;

  //convert macro text to VN standard
  m_table[m_count].textOffset = offset;
  inLen = -1; //input is null-terminated
  maxOutLen = MAX_MACRO_TEXT_LEN * sizeof(StdVnChar);
  if (maxOutLen + offset > m_memSize)
    maxOutLen = m_memSize - offset;
  ret = VnConvert(charset, CONV_CHARSET_VNSTANDARD,
		  (UKBYTE *)text, (UKBYTE *)p,
		  &inLen, &maxOutLen);
  if (ret != 0)
    return -1;

  m_occupied = offset + maxOutLen;
  m_count++;
  return (m_count-1);
}

//---------------------------------------------------------------
// add a new macro into the sorted macro table
// item format: key:text (key and text are separated by a colon)
//---------------------------------------------------------------
int CMacroTable::addItem(const char *item, int charset)
{
  char key[MAX_MACRO_KEY_LEN];

  // Parse the input item
  char * pos = (char*)strchr(item, ':');
  if (pos == NULL)
    return -1;
  int keyLen = (int)(pos - item);
  if (keyLen > MAX_MACRO_KEY_LEN-1)
    keyLen = MAX_MACRO_KEY_LEN-1;
  strncpy(key, item, keyLen);
  key[keyLen] = '\0';
  return addItem(key, ++pos, charset);
}

//---------------------------------------------------------------
void CMacroTable::resetContent()
{
  m_occupied = 0;
  m_count = 0;
}

//---------------------------------------------------------------
const StdVnChar *CMacroTable::getKey(int idx) const
{
    if (idx < 0 || idx >= m_count)
        return 0;
    return (StdVnChar *)(m_macroMem + m_table[idx].keyOffset);
}

//---------------------------------------------------------------
const StdVnChar *CMacroTable::getText(int idx) const
{
    if (idx < 0 || idx >= m_count)
        return 0;
    return (StdVnChar *)(m_macroMem + m_table[idx].textOffset);
}