//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
//
// copyright            : (C) 2008 by Eran Ifrah
// file name            : cppwordscanner.cpp
//
// -------------------------------------------------------------------------
// A
//              _____           _      _     _ _
//             /  __ \         | |    | |   (_) |
//             | /  \/ ___   __| | ___| |    _| |_ ___
//             | |    / _ \ / _  |/ _ \ |   | | __/ _ )
//             | \__/\ (_) | (_| |  __/ |___| | ||  __/
//              \____/\___/ \__,_|\___\_____/_|\__\___|
//
//                                                  F i l e
//
//    This program is free software; you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation; either version 2 of the License, or
//    (at your option) any later version.
//
//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
#include <wx/ffile.h>
#include <wx/strconv.h>
#include <wx/tokenzr.h>
#include <wx/log.h>
#include "cppwordscanner.h"
#include "stringaccessor.h"
#include "dirsaver.h"

CppWordScanner::CppWordScanner(const wxString &fileName)
	: m_filename(fileName)
	, m_offset(0)
{
	// disable log
	wxLogNull nolog;

	wxFFile thefile(fileName, wxT("rb"));
	if(thefile.IsOpened()) {
		wxFileOffset size = thefile.Length();
		wxString fileData;
		fileData.Alloc(size);

		wxCSConv fontEncConv(wxFONTENCODING_ISO8859_1);
		thefile.ReadAll( &m_text, fontEncConv );
	}
	doInit();
}

CppWordScanner::CppWordScanner(const wxString& fileName, const wxString& text, int offset)
	: m_filename(fileName)
	, m_text    (text.c_str())
	, m_offset  (offset)
{
	doInit();
}

CppWordScanner::~CppWordScanner()
{
}

void CppWordScanner::FindAll(CppTokensMap &tokensMap)
{
	doFind(wxEmptyString, tokensMap, wxNOT_FOUND, wxNOT_FOUND);
}

void CppWordScanner::Match(const wxString& word, CppTokensMap& l)
{
	// scan the entire text
	doFind(word, l, wxNOT_FOUND, wxNOT_FOUND);
}

void CppWordScanner::Match(const wxString& word, CppTokensMap& l, int from, int to)
{
	// scan the entire text
	doFind(word, l, from, to);
}

void CppWordScanner::doFind(const wxString& filter, CppTokensMap& l, int from, int to)
{
	int state(STATE_NORMAL);
	StringAccessor accessor(m_text);
	CppToken token;
	int lineNo(0);
	
	// set the scan range
	size_t f = (from == wxNOT_FOUND) ? 0             : from;
	size_t t = (to   == wxNOT_FOUND) ? m_text.size() : to;

	// sanity
	if(f > m_text.size() || t > m_text.size())
		return;

	for (size_t i=f; i<t; i++) {
		char ch = accessor.safeAt(i);
		
		// Keep track of line numbers
		if(accessor.match("\n", i) && (state == STATE_NORMAL || state == STATE_PRE_PROCESSING || state == STATE_CPP_COMMENT || state == STATE_C_COMMENT)){
			lineNo++;
		}
		
		switch (state) {

		case STATE_NORMAL:
			if (accessor.match("#", i)) {

				if (	i == 0 || 						// satrt of document
				        accessor.match("\n", i-1)) { 	// we are at start of line
					state = STATE_PRE_PROCESSING;
				}
			} else if (accessor.match("//", i)) {

				// C++ comment, advance i
				state = STATE_CPP_COMMENT;
				i++;

			} else if (accessor.match("/*", i)) {

				// C comment
				state = STATE_C_COMMENT;
				i++;

			} else if (accessor.match("'", i)) {

				// single quoted string
				state = STATE_SINGLE_STRING;

			} else if (accessor.match("\"", i)) {

				// dbouble quoted string
				state = STATE_DQ_STRING;

			} else if ( accessor.isWordChar(ch) ) {

				// is valid C++ word?
				token.append( ch );
				if (token.getOffset() == wxString::npos) {
					token.setOffset( i + m_offset );
				}
			} else {

				if (token.getName().empty() == false) {

					if ((int)token.getName().GetChar(0) >= 48 && (int)token.getName().GetChar(0) <= 57) {
						token.reset();
					} else {
						//dont add C++ key words
						if (m_arr.Index(token.getName()) == wxNOT_FOUND) {

							// Ok, we are not a number!
							// filter out non matching words
							if (filter.empty() || filter == token.getName()) {
								token.setFilename(m_filename);
								token.setLineNumber(lineNo);
								l.addToken(token);
							}
						}
						token.reset();
					}
				}
			}

			break;
		case STATE_PRE_PROCESSING:
			// if the char before the \n is \ (backslash) or \r\ (CR followed by backslash) remain in pre-processing state
			if ( accessor.match("\n", i) && (!accessor.match("\\", i-1) && !accessor.match("\\\r", i-2)) ) {
				// no wrap
				state = STATE_NORMAL;

			} else if ( accessor.match("//", i)) {
				// C++ comment, advance i
				state = STATE_CPP_COMMENT;
				i++;
			}
			break;
		case STATE_C_COMMENT:
			if ( accessor.match("*/", i)) {
				state = STATE_NORMAL;
				i++;
			}
			break;
		case STATE_CPP_COMMENT:
			if ( accessor.match("\n", i)) {
				state = STATE_NORMAL;
			}
			break;
		case STATE_DQ_STRING:
			if (accessor.match("\\\"", i)) {
				//escaped string
				i++;
			} else if(accessor.match("\\", i)) {
				i++;
			} else if (accessor.match("\"", i)) {
				state = STATE_NORMAL;
			}
			break;
		case STATE_SINGLE_STRING:
			if (accessor.match("\\'", i)) {
				//escaped single string
				i++;

			} else if(accessor.match("\\", i)) {
				i++;

			} else if (accessor.match("'", i)) {
				state = STATE_NORMAL;
			}
			break;
		}
	}
}

void CppWordScanner::doInit()
{
	wxString key_words =
	    wxT("auto break case char const continue default define defined do double elif else endif enum error extern float"
	        "for  goto if ifdef ifndef include int long pragma register return short signed sizeof static struct switch"
	        "typedef undef union unsigned void volatile while class namespace delete friend inline new operator overload"
	        "protected private public this virtual template typename dynamic_cast static_cast const_cast reinterpret_cast"
	        "using throw catch size_t");

	//add this items into map
	wxArrayString tmpArr = wxStringTokenize(key_words, wxT(" "));
	for(size_t i=0; i<tmpArr.GetCount(); i++) {
		m_arr.Add(tmpArr.Item(i).c_str());
	}
	m_arr.Sort();
}

TextStatesPtr CppWordScanner::states()
{
	TextStatesPtr bitmap (new TextStates());
	bitmap->states.resize(m_text.size());

	if(bitmap->states.size() == 0) {
		return NULL;
	}

	bitmap->text = m_text.c_str();

	int state(STATE_NORMAL);
	int depth(0);
	int lineNo(0);

	StringAccessor accessor(m_text.c_str());

	for (size_t i=0; i<m_text.size(); i++) {

		// Keep track of line numbers
		if(accessor.match("\n", i) && (state == STATE_NORMAL || state == STATE_PRE_PROCESSING || state == STATE_CPP_COMMENT || state == STATE_C_COMMENT)){
			lineNo++;
		}

		switch (state) {

		case STATE_NORMAL:
			if (accessor.match("#", i)) {

				if ( i == 0 ||                    // satrt of document
				     accessor.match("\n", i-1)) { // we are at start of line
					state = STATE_PRE_PROCESSING;
				}

			} else if (accessor.match("//", i)) {

				// C++ comment, advance i
				state = STATE_CPP_COMMENT;
				bitmap->SetState(i, STATE_CPP_COMMENT, depth, lineNo);
				i++;

			} else if (accessor.match("/*", i)) {

				// C comment
				state = STATE_C_COMMENT;
				bitmap->SetState(i, STATE_C_COMMENT, depth, lineNo);
				i++;

			} else if (accessor.match("'", i)) {

				// single quoted string
				state = STATE_SINGLE_STRING;

			} else if (accessor.match("\"", i)) {

				// dbouble quoted string
				state = STATE_DQ_STRING;

			} else if (accessor.match("{", i)) {
				depth++;

			} else if (accessor.match("}", i)) {
				depth--;

			}

			break;
		case STATE_PRE_PROCESSING:
			// if the char before the \n is \ (backslash) or \r\ (CR followed by backslash) remain in pre-processing state
			if ( accessor.match("\n", i) && (!accessor.match("\\", i-1) && !accessor.match("\\\r", i-2)) ) {
				// no wrap
				state = STATE_NORMAL;

			} else if ( accessor.match("//", i)) {
				// C++ comment, advance i
				state = STATE_CPP_COMMENT;
				bitmap->SetState(i, STATE_CPP_COMMENT, depth, lineNo);
				i++;
			}
			break;
		case STATE_C_COMMENT:
			if ( accessor.match("*/", i)) {
				bitmap->SetState(i, state, depth, lineNo);
				state = STATE_NORMAL;
				i++;
			}
			break;
		case STATE_CPP_COMMENT:
			if ( accessor.match("\n", i)) {
				state = STATE_NORMAL;
			}
			break;
		case STATE_DQ_STRING:
			if (accessor.match("\\\"", i)) {
				//escaped string
				bitmap->SetState(i, STATE_DQ_STRING, depth, lineNo);
				i++;

			} else if(accessor.match("\\", i)) {
				bitmap->SetState(i, STATE_DQ_STRING, depth, lineNo);
				i++;

			} else if (accessor.match("\"", i)) {
				state = STATE_NORMAL;
			}
			break;
		case STATE_SINGLE_STRING:
			if (accessor.match("\\'", i)) {
				//escaped single string
				bitmap->SetState(i, STATE_SINGLE_STRING, depth, lineNo);
				i++;
			} else if(accessor.match("\\", i)) {
				bitmap->SetState(i, STATE_SINGLE_STRING, depth, lineNo);
				i++;

			} else if (accessor.match("'", i)) {
				state = STATE_NORMAL;
			}
			break;
		}
		bitmap->SetState(i, state, depth, lineNo);
	}
	return bitmap;
}

int TextStates::FunctionEndPos(int position)
{
	// Sanity
	if(text.Len() != states.size())
		return wxNOT_FOUND;

	if(position < 0)
		return wxNOT_FOUND;

	if(position >= (int)text.Len())
		return wxNOT_FOUND;

	if(states[position].depth < 0) {
		// we are already at depth 0 (which means global scope)
		return wxNOT_FOUND;
	}

	// Note that each call to 'Next' / 'Prev' updates the 'pos' member
	int curdepth = states[position].depth;

	// Step 1: search from this point downward until we find an opening brace (i.e. depth is equal to curdepth+1)
	SetPosition(position);

	wxChar ch = Next();
	while ( ch ) {
		if(states[pos].depth == curdepth + 1)
			break;
		ch = Next();
	}

	// Step 2: Continue from the current position,
	// but this time break when depth is curdepth

	ch = Next();
	while ( ch ) {
		if(states[pos].depth == curdepth)
			break;
		ch = Next();
	}

	if(pos > position) {
		return pos;
	}

	return wxNOT_FOUND;
}

wxChar TextStates::Next()
{
	if(text.Len() != states.size())
		return 0;

	if(pos == wxNOT_FOUND)
		return 0;

	// reached end of text
	pos++;
	while( pos < (int)text.Len() ) {
		int st = states[pos].state;
		if(st == CppWordScanner::STATE_NORMAL) {
			if(text.Len() > (size_t)pos)
				return text.GetChar(pos);;
			return 0;
		}
		pos++;
	}
	return 0;
}

wxChar TextStates::Previous()
{
	if(text.Len() != states.size())
		return 0;

	if(pos == wxNOT_FOUND)
		return 0;

	// reached start of text
	if(pos == 0)
		return 0;

	pos--;
	while( pos ) {
		int st = states[pos].state;
		if(st == CppWordScanner::STATE_NORMAL) {
			if(text.Len() > (size_t)pos)
				return text.GetChar(pos);
			return 0;
		}
		pos--;
	}
	return 0;
}

void TextStates::SetPosition(int pos)
{
	this->pos = pos;
}

void TextStates::SetState(size_t where, int state, int depth, int lineNo)
{
	if(where < states.size()) {
		states[where].depth   = depth;
		states[where].state   = state;
		states[where].lineNo  = lineNo;
	}

	if(lineToPos.empty() || (int)lineToPos.size() - 1 < lineNo) {
		lineToPos.push_back( where );
	}
}

int TextStates::LineToPos(int lineNo)
{
	if(IsOk() == false)
		return wxNOT_FOUND;

	if(lineToPos.empty() || (int)lineToPos.size() < lineNo || lineNo < 0)
		return wxNOT_FOUND;

	return lineToPos.at(lineNo);
}
