// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
// Original code is licensed as follows:
/*
 * Copyright 2006-2007 Jeremias Maerki.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "../barcode.h"
#include "../BC_Dimension.h"
#include "../common/BC_CommonBitMatrix.h"
#include "BC_Encoder.h"
#include "BC_SymbolShapeHint.h"
#include "BC_SymbolInfo.h"
#include "BC_EncoderContext.h"
#include "BC_HighLevelEncoder.h"
#include "BC_C40Encoder.h"
CBC_C40Encoder::CBC_C40Encoder()
{
}
CBC_C40Encoder::~CBC_C40Encoder()
{
}
FX_INT32 CBC_C40Encoder::getEncodingMode()
{
    return C40_ENCODATION;
}
void CBC_C40Encoder::Encode(CBC_EncoderContext &context, FX_INT32 &e)
{
    CFX_WideString buffer;
    while (context.hasMoreCharacters()) {
        FX_WCHAR c = context.getCurrentChar();
        context.m_pos++;
        FX_INT32 lastCharSize = encodeChar(c, buffer, e);
        if (e != BCExceptionNO) {
            return;
        }
        FX_INT32 unwritten = (buffer.GetLength() / 3) * 2;
        FX_INT32 curCodewordCount = context.getCodewordCount() + unwritten;
        context.updateSymbolInfo(curCodewordCount, e);
        if (e != BCExceptionNO) {
            return;
        }
        FX_INT32 available = context.m_symbolInfo->m_dataCapacity - curCodewordCount;
        if (!context.hasMoreCharacters()) {
            CFX_WideString removed;
            if ((buffer.GetLength() % 3) == 2) {
                if (available < 2 || available > 2) {
                    lastCharSize = backtrackOneCharacter(context, buffer, removed, lastCharSize, e);
                    if (e != BCExceptionNO) {
                        return;
                    }
                }
            }
            while ((buffer.GetLength() % 3) == 1
                    && ((lastCharSize <= 3 && available != 1) || lastCharSize > 3)) {
                lastCharSize = backtrackOneCharacter(context, buffer, removed, lastCharSize, e);
                if (e != BCExceptionNO) {
                    return;
                }
            }
            break;
        }
        FX_INT32 count = buffer.GetLength();
        if ((count % 3) == 0) {
            FX_INT32 newMode = CBC_HighLevelEncoder::lookAheadTest(context.m_msg, context.m_pos, getEncodingMode());
            if (newMode != getEncodingMode()) {
                context.signalEncoderChange(newMode);
                break;
            }
        }
    }
    handleEOD(context, buffer, e);
}
void CBC_C40Encoder::writeNextTriplet(CBC_EncoderContext &context, CFX_WideString &buffer)
{
    context.writeCodewords(encodeToCodewords(buffer, 0));
    buffer.Delete(0, 3);
}
void CBC_C40Encoder::handleEOD(CBC_EncoderContext &context, CFX_WideString &buffer, FX_INT32 &e)
{
    FX_INT32 unwritten = (buffer.GetLength() / 3) * 2;
    FX_INT32 rest = buffer.GetLength() % 3;
    FX_INT32 curCodewordCount = context.getCodewordCount() + unwritten;
    context.updateSymbolInfo(curCodewordCount, e);
    if (e != BCExceptionNO) {
        return;
    }
    FX_INT32 available = context.m_symbolInfo->m_dataCapacity - curCodewordCount;
    if (rest == 2) {
        buffer += (FX_WCHAR)'\0';
        while (buffer.GetLength() >= 3) {
            writeNextTriplet(context, buffer);
        }
        if (context.hasMoreCharacters()) {
            context.writeCodeword(CBC_HighLevelEncoder::C40_UNLATCH);
        }
    } else if (available == 1 && rest == 1) {
        while (buffer.GetLength() >= 3) {
            writeNextTriplet(context, buffer);
        }
        if (context.hasMoreCharacters()) {
            context.writeCodeword(CBC_HighLevelEncoder::C40_UNLATCH);
        }
        context.m_pos--;
    } else if (rest == 0) {
        while (buffer.GetLength() >= 3) {
            writeNextTriplet(context, buffer);
        }
        if (available > 0 || context.hasMoreCharacters()) {
            context.writeCodeword(CBC_HighLevelEncoder::C40_UNLATCH);
        }
    } else {
        e = BCExceptionIllegalStateUnexpectedCase;
        return;
    }
    context.signalEncoderChange(ASCII_ENCODATION);
}
FX_INT32 CBC_C40Encoder::encodeChar(FX_WCHAR c, CFX_WideString &sb, FX_INT32 &e)
{
    if (c == ' ') {
        sb += (FX_WCHAR)'\3';
        return 1;
    } else if ((c >= '0') && (c <= '9')) {
        sb += (FX_WCHAR)(c - 48 + 4);
        return 1;
    } else if ((c >= 'A') && (c <= 'Z')) {
        sb += (FX_WCHAR)(c - 65 + 14);
        return 1;
    } else if ((c >= '\0') && (c <= 0x1f)) {
        sb += (FX_WCHAR)'\0';
        sb += c;
        return 2;
    } else if ((c >= '!') && (c <= '/')) {
        sb += (FX_WCHAR)'\1';
        sb += (FX_WCHAR)(c - 33);
        return 2;
    } else if ((c >= ':') && (c <= '@')) {
        sb += (FX_WCHAR)'\1';
        sb += (FX_WCHAR)(c - 58 + 15);
        return 2;
    } else if ((c >= '[') && (c <= '_')) {
        sb += (FX_WCHAR)'\1';
        sb += (FX_WCHAR)(c - 91 + 22);
        return 2;
    } else if ((c >= 60) && (c <= 0x7f)) {
        sb += (FX_WCHAR)'\2';
        sb += (FX_WCHAR)(c - 96);
        return 2;
    } else if (c >= 80) {
        sb += (FX_WCHAR)'\1';
        sb += (FX_WCHAR)0x001e;
        FX_INT32 len = 2;
        len += encodeChar((c - 128), sb, e);
        BC_EXCEPTION_CHECK_ReturnValue(e,  0);
        return len;
    } else {
        e = BCExceptionIllegalArgument;
        return 0;
    }
}
FX_INT32 CBC_C40Encoder::backtrackOneCharacter(CBC_EncoderContext &context, CFX_WideString &buffer, CFX_WideString &removed, FX_INT32 lastCharSize, FX_INT32 &e)
{
    FX_INT32 count = buffer.GetLength();
    buffer.Delete(count - lastCharSize, count);
    context.m_pos--;
    FX_WCHAR c = context.getCurrentChar();
    lastCharSize = encodeChar(c, removed, e);
    BC_EXCEPTION_CHECK_ReturnValue(e,  -1);
    context.resetSymbolInfo();
    return lastCharSize;
}
CFX_WideString CBC_C40Encoder::encodeToCodewords(CFX_WideString sb, FX_INT32 startPos)
{
    FX_WCHAR c1 = sb.GetAt(startPos);
    FX_WCHAR c2 = sb.GetAt(startPos + 1);
    FX_WCHAR c3 = sb.GetAt(startPos + 2);
    FX_INT32 v = (1600 * c1) + (40 * c2) + c3 + 1;
    FX_WCHAR cw1 = (FX_WCHAR) (v / 256);
    FX_WCHAR cw2 = (FX_WCHAR) (v % 256);
    CFX_WideString b1(cw1);
    CFX_WideString b2(cw2);
    return b1 + b2;
}