// 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

#include "../../../include/fpdfapi/fpdf_parser.h"
extern const FX_LPCSTR _PDF_CharType =
    "WRRRRRRRRWWRWWRRRRRRRRRRRRRRRRRR"
    "WRRRRDRRDDRNRNNDNNNNNNNNNNRRDRDR"
    "RRRRRRRRRRRRRRRRRRRRRRRRRRRDRDRR"
    "RRRRRRRRRRRRRRRRRRRRRRRRRRRDRDRR"
    "WRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
    "RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
    "RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
    "RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRW";
#ifndef MAX_PATH
#define MAX_PATH 4096
#endif
CPDF_SimpleParser::CPDF_SimpleParser(FX_LPCBYTE pData, FX_DWORD dwSize)
{
    m_pData = pData;
    m_dwSize = dwSize;
    m_dwCurPos = 0;
}
CPDF_SimpleParser::CPDF_SimpleParser(FX_BSTR str)
{
    m_pData = str;
    m_dwSize = str.GetLength();
    m_dwCurPos = 0;
}
void CPDF_SimpleParser::ParseWord(FX_LPCBYTE& pStart, FX_DWORD& dwSize, int& type)
{
    pStart = NULL;
    dwSize = 0;
    type = PDFWORD_EOF;
    FX_BYTE ch;
    char chartype;
    while (1) {
        if (m_dwSize <= m_dwCurPos) {
            return;
        }
        ch = m_pData[m_dwCurPos++];
        chartype = _PDF_CharType[ch];
        while (chartype == 'W') {
            if (m_dwSize <= m_dwCurPos) {
                return;
            }
            ch = m_pData[m_dwCurPos++];
            chartype = _PDF_CharType[ch];
        }
        if (ch != '%') {
            break;
        }
        while (1) {
            if (m_dwSize <= m_dwCurPos) {
                return;
            }
            ch = m_pData[m_dwCurPos++];
            if (ch == '\r' || ch == '\n') {
                break;
            }
        }
        chartype = _PDF_CharType[ch];
    }
    FX_DWORD start_pos = m_dwCurPos - 1;
    pStart = m_pData + start_pos;
    if (chartype == 'D') {
        if (ch == '/') {
            while (1) {
                if (m_dwSize <= m_dwCurPos) {
                    return;
                }
                ch = m_pData[m_dwCurPos++];
                chartype = _PDF_CharType[ch];
                if (chartype != 'R' && chartype != 'N') {
                    m_dwCurPos --;
                    dwSize = m_dwCurPos - start_pos;
                    type = PDFWORD_NAME;
                    return;
                }
            }
        } else {
            type = PDFWORD_DELIMITER;
            dwSize = 1;
            if (ch == '<') {
                if (m_dwSize <= m_dwCurPos) {
                    return;
                }
                ch = m_pData[m_dwCurPos++];
                if (ch == '<') {
                    dwSize = 2;
                } else {
                    m_dwCurPos --;
                }
            } else if (ch == '>') {
                if (m_dwSize <= m_dwCurPos) {
                    return;
                }
                ch = m_pData[m_dwCurPos++];
                if (ch == '>') {
                    dwSize = 2;
                } else {
                    m_dwCurPos --;
                }
            }
        }
        return;
    }
    type = PDFWORD_NUMBER;
    dwSize = 1;
    while (1) {
        if (chartype != 'N') {
            type = PDFWORD_TEXT;
        }
        if (m_dwSize <= m_dwCurPos) {
            return;
        }
        ch = m_pData[m_dwCurPos++];
        chartype = _PDF_CharType[ch];
        if (chartype == 'D' || chartype == 'W') {
            m_dwCurPos --;
            break;
        }
        dwSize ++;
    }
}
CFX_ByteStringC CPDF_SimpleParser::GetWord()
{
    FX_LPCBYTE pStart;
    FX_DWORD dwSize;
    int type;
    ParseWord(pStart, dwSize, type);
    if (dwSize == 1 && pStart[0] == '<') {
        while (m_dwCurPos < m_dwSize && m_pData[m_dwCurPos] != '>') {
            m_dwCurPos ++;
        }
        if (m_dwCurPos < m_dwSize) {
            m_dwCurPos ++;
        }
        return CFX_ByteStringC(pStart, (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
    } else if (dwSize == 1 && pStart[0] == '(') {
        int level = 1;
        while (m_dwCurPos < m_dwSize) {
            if (m_pData[m_dwCurPos] == ')') {
                level --;
                if (level == 0) {
                    break;
                }
            }
            if (m_pData[m_dwCurPos] == '\\') {
                if (m_dwSize <= m_dwCurPos) {
                    break;
                }
                m_dwCurPos ++;
            } else if (m_pData[m_dwCurPos] == '(') {
                level ++;
            }
            if (m_dwSize <= m_dwCurPos) {
                break;
            }
            m_dwCurPos ++;
        }
        if (m_dwCurPos < m_dwSize) {
            m_dwCurPos ++;
        }
        return CFX_ByteStringC(pStart, (FX_STRSIZE)(m_dwCurPos - (pStart - m_pData)));
    }
    return CFX_ByteStringC(pStart, dwSize);
}
FX_BOOL CPDF_SimpleParser::SearchToken(FX_BSTR token)
{
    int token_len = token.GetLength();
    while (m_dwCurPos < m_dwSize - token_len) {
        if (FXSYS_memcmp32(m_pData + m_dwCurPos, token, token_len) == 0) {
            break;
        }
        m_dwCurPos ++;
    }
    if (m_dwCurPos == m_dwSize - token_len) {
        return FALSE;
    }
    m_dwCurPos += token_len;
    return TRUE;
}
FX_BOOL CPDF_SimpleParser::SkipWord(FX_BSTR token)
{
    while (1) {
        CFX_ByteStringC word = GetWord();
        if (word.IsEmpty()) {
            return FALSE;
        }
        if (word == token) {
            return TRUE;
        }
    }
    return FALSE;
}
FX_BOOL CPDF_SimpleParser::FindTagPair(FX_BSTR start_token, FX_BSTR end_token,
                                       FX_DWORD& start_pos, FX_DWORD& end_pos)
{
    if (!start_token.IsEmpty()) {
        if (!SkipWord(start_token)) {
            return FALSE;
        }
        start_pos = m_dwCurPos;
    }
    while (1) {
        end_pos = m_dwCurPos;
        CFX_ByteStringC word = GetWord();
        if (word.IsEmpty()) {
            return FALSE;
        }
        if (word == end_token) {
            return TRUE;
        }
    }
    return FALSE;
}
FX_BOOL CPDF_SimpleParser::FindTagParam(FX_BSTR token, int nParams)
{
    nParams ++;
    FX_DWORD* pBuf = FX_Alloc(FX_DWORD, nParams);
    int buf_index = 0;
    int buf_count = 0;
    while (1) {
        pBuf[buf_index++] = m_dwCurPos;
        if (buf_index == nParams) {
            buf_index = 0;
        }
        buf_count ++;
        if (buf_count > nParams) {
            buf_count = nParams;
        }
        CFX_ByteStringC word = GetWord();
        if (word.IsEmpty()) {
            FX_Free(pBuf);
            return FALSE;
        }
        if (word == token) {
            if (buf_count < nParams) {
                continue;
            }
            m_dwCurPos = pBuf[buf_index];
            FX_Free(pBuf);
            return TRUE;
        }
    }
    return FALSE;
}
static int _hex2dec(char ch)
{
    if (ch >= '0' && ch <= '9') {
        return ch - '0';
    }
    if (ch >= 'a' && ch <= 'f') {
        return ch - 'a' + 10;
    }
    if (ch >= 'A' && ch <= 'F') {
        return ch - 'A' + 10;
    }
    return 0;
}
CFX_ByteString PDF_NameDecode(FX_BSTR bstr)
{
    int size = bstr.GetLength();
    FX_LPCSTR pSrc = bstr.GetCStr();
    if (FXSYS_memchr(pSrc, '#', size) == NULL) {
        return bstr;
    }
    CFX_ByteString result;
    FX_LPSTR pDestStart = result.GetBuffer(size);
    FX_LPSTR pDest = pDestStart;
    for (int i = 0; i < size; i ++) {
        if (pSrc[i] == '#' && i < size - 2) {
            *pDest ++ = _hex2dec(pSrc[i + 1]) * 16 + _hex2dec(pSrc[i + 2]);
            i += 2;
        } else {
            *pDest ++ = pSrc[i];
        }
    }
    result.ReleaseBuffer((FX_STRSIZE)(pDest - pDestStart));
    return result;
}
CFX_ByteString PDF_NameDecode(const CFX_ByteString& orig)
{
    if (FXSYS_memchr(orig.c_str(), '#', orig.GetLength()) == NULL) {
        return orig;
    }
    return PDF_NameDecode(CFX_ByteStringC(orig));
}
CFX_ByteString PDF_NameEncode(const CFX_ByteString& orig)
{
    FX_LPBYTE src_buf = (FX_LPBYTE)orig.c_str();
    int src_len = orig.GetLength();
    int dest_len = 0;
    int i;
    for (i = 0; i < src_len; i ++) {
        FX_BYTE ch = src_buf[i];
        if (ch >= 0x80 || _PDF_CharType[ch] == 'W' || ch == '#' ||
                _PDF_CharType[ch] == 'D') {
            dest_len += 3;
        } else {
            dest_len ++;
        }
    }
    if (dest_len == src_len) {
        return orig;
    }
    CFX_ByteString res;
    FX_LPSTR dest_buf = res.GetBuffer(dest_len);
    dest_len = 0;
    for (i = 0; i < src_len; i ++) {
        FX_BYTE ch = src_buf[i];
        if (ch >= 0x80 || _PDF_CharType[ch] == 'W' || ch == '#' ||
                _PDF_CharType[ch] == 'D') {
            dest_buf[dest_len++] = '#';
            dest_buf[dest_len++] = "0123456789ABCDEF"[ch / 16];
            dest_buf[dest_len++] = "0123456789ABCDEF"[ch % 16];
        } else {
            dest_buf[dest_len++] = ch;
        }
    }
    dest_buf[dest_len] = 0;
    res.ReleaseBuffer();
    return res;
}
CFX_ByteTextBuf& operator << (CFX_ByteTextBuf& buf, const CPDF_Object* pObj)
{
    if (pObj == NULL) {
        buf << FX_BSTRC(" null");
        return buf;
    }
    switch (pObj->GetType()) {
        case PDFOBJ_NULL:
            buf << FX_BSTRC(" null");
            break;
        case PDFOBJ_BOOLEAN:
        case PDFOBJ_NUMBER:
            buf << " " << pObj->GetString();
            break;
        case PDFOBJ_STRING: {
                CFX_ByteString str = pObj->GetString();
                FX_BOOL bHex = ((CPDF_String*)pObj)->IsHex();
                buf << PDF_EncodeString(str, bHex);
                break;
            }
        case PDFOBJ_NAME: {
                CFX_ByteString str = pObj->GetString();
                buf << FX_BSTRC("/") << PDF_NameEncode(str);
                break;
            }
        case PDFOBJ_REFERENCE: {
                CPDF_Reference* p = (CPDF_Reference*)pObj;
                buf << " " << p->GetRefObjNum() << FX_BSTRC(" 0 R ");
                break;
            }
        case PDFOBJ_ARRAY: {
                CPDF_Array* p = (CPDF_Array*)pObj;
                buf << FX_BSTRC("[");
                for (FX_DWORD i = 0; i < p->GetCount(); i ++) {
                    CPDF_Object* pElement = p->GetElement(i);
                    if (pElement->GetObjNum()) {
                        buf << " " << pElement->GetObjNum() << FX_BSTRC(" 0 R");
                    } else {
                        buf << pElement;
                    }
                }
                buf << FX_BSTRC("]");
                break;
            }
        case PDFOBJ_DICTIONARY: {
                CPDF_Dictionary* p = (CPDF_Dictionary*)pObj;
                buf << FX_BSTRC("<<");
                FX_POSITION pos = p->GetStartPos();
                while (pos) {
                    CFX_ByteString key;
                    CPDF_Object* pValue = p->GetNextElement(pos, key);
                    buf << FX_BSTRC("/") << PDF_NameEncode(key);
                    if (pValue->GetObjNum()) {
                        buf << " " << pValue->GetObjNum() << FX_BSTRC(" 0 R ");
                    } else {
                        buf << pValue;
                    }
                }
                buf << FX_BSTRC(">>");
                break;
            }
        case PDFOBJ_STREAM: {
                CPDF_Stream* p = (CPDF_Stream*)pObj;
                buf << p->GetDict() << FX_BSTRC("stream\r\n");
                CPDF_StreamAcc acc;
                acc.LoadAllData(p, TRUE);
                buf.AppendBlock(acc.GetData(), acc.GetSize());
                buf << FX_BSTRC("\r\nendstream");
                break;
            }
        default:
            ASSERT(FALSE);
            break;
    }
    return buf;
}
FX_FLOAT PDF_ClipFloat(FX_FLOAT f)
{
    if (f < 0) {
        return 0;
    }
    if (f > 1.0f) {
        return 1.0f;
    }
    return f;
}
static CPDF_Object* SearchNumberNode(CPDF_Dictionary* pNode, int num)
{
    CPDF_Array* pLimits = pNode->GetArray("Limits");
    if (pLimits && (num < pLimits->GetInteger(0) || num > pLimits->GetInteger(1))) {
        return NULL;
    }
    CPDF_Array* pNumbers = pNode->GetArray("Nums");
    if (pNumbers) {
        FX_DWORD dwCount = pNumbers->GetCount() / 2;
        for (FX_DWORD i = 0; i < dwCount; i ++) {
            int index = pNumbers->GetInteger(i * 2);
            if (num == index) {
                return pNumbers->GetElementValue(i * 2 + 1);
            }
            if (index > num) {
                break;
            }
        }
        return NULL;
    }
    CPDF_Array* pKids = pNode->GetArray("Kids");
    if (pKids == NULL) {
        return NULL;
    }
    for (FX_DWORD i = 0; i < pKids->GetCount(); i ++) {
        CPDF_Dictionary* pKid = pKids->GetDict(i);
        if (pKid == NULL) {
            continue;
        }
        CPDF_Object* pFound = SearchNumberNode(pKid, num);
        if (pFound) {
            return pFound;
        }
    }
    return NULL;
}
CPDF_Object* CPDF_NumberTree::LookupValue(int num)
{
    return SearchNumberNode(m_pRoot, num);
}