// Scintilla source code edit control
//Author: instanton (email: soft_share<at>126<dot>com)
// The License.txt file describes the conditions under which this software may be distributed.

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>

#include "ILexer.h"
#include "Scintilla.h"
#include "SciLexer.h"

#include "WordList.h"
#include "LexAccessor.h"
#include "Accessor.h"
#include "StyleContext.h"
#include "CharacterSet.h"
#include "LexerModule.h"

#ifdef SCI_NAMESPACE
using namespace Scintilla;
#endif

static void ColouriseAsyDoc(unsigned int startPos, int length, int initStyle,
        WordList *keywordlists[], Accessor &styler) {

    WordList &keywords = *keywordlists[0];
    WordList &keywords2 = *keywordlists[1];

    CharacterSet setWordStart(CharacterSet::setAlpha, "_", 0x80, true);
    CharacterSet setWord(CharacterSet::setAlphaNum, "._", 0x80, true);

    int visibleChars = 0;

    StyleContext sc(startPos, length, initStyle, styler);

    for (; sc.More(); sc.Forward()) {

        if (sc.atLineStart) {
            if (sc.state == SCE_ASY_STRING) {
                sc.SetState(SCE_ASY_STRING);
            }
            visibleChars = 0;
        }

        if (sc.ch == '\\') {
            if (sc.chNext == '\n' || sc.chNext == '\r') {
                sc.Forward();
                if (sc.ch == '\r' && sc.chNext == '\n') {
                    sc.Forward();
                }
//              continuationLine = true;
                continue;
            }
        }

        // Determine if the current state should terminate.
        switch (sc.state) {
            case SCE_ASY_OPERATOR:
                sc.SetState(SCE_ASY_DEFAULT);
                break;
            case SCE_ASY_NUMBER:
                if (!setWord.Contains(sc.ch)) {
                    sc.SetState(SCE_ASY_DEFAULT);
                }
                break;
            case SCE_ASY_IDENTIFIER:
                if (!setWord.Contains(sc.ch) || (sc.ch == '.')) {
                    char s[1000];
                    sc.GetCurrentLowered(s, sizeof(s));
                    if (keywords.InList(s)) {
                        sc.ChangeState(SCE_ASY_WORD);
                    } else if (keywords2.InList(s)) {
                        sc.ChangeState(SCE_ASY_WORD2);
                    }
                    sc.SetState(SCE_ASY_DEFAULT);
                }
                break;
            case SCE_ASY_COMMENT:
                if (sc.Match('*', '/')) {
                    sc.Forward();
                    sc.ForwardSetState(SCE_ASY_DEFAULT);
                }
                break;
            case SCE_ASY_COMMENTLINE:
                if (sc.atLineStart) {
                    sc.SetState(SCE_ASY_DEFAULT);
                }
                break;
            case SCE_ASY_STRING:
                if (sc.atLineEnd) {
                    sc.ChangeState(SCE_ASY_STRINGEOL);
                } else if (sc.ch == '\\') {
                    if (sc.chNext == '\"' || sc.chNext == '\'' || sc.chNext == '\\') {
                        sc.Forward();
                    }
                } else if (sc.ch == '\"') {
                    sc.ForwardSetState(SCE_ASY_DEFAULT);
                }
                break;
            case SCE_ASY_CHARACTER:
                if (sc.atLineEnd) {
                    sc.ChangeState(SCE_ASY_STRINGEOL);
                } else  if (sc.ch == '\\') {
                    if (sc.chNext == '\"' || sc.chNext == '\'' || sc.chNext == '\\') {
                        sc.Forward();
                    }
                } else if (sc.ch == '\'') {
                    sc.ForwardSetState(SCE_ASY_DEFAULT);
                }
                break;
        }

        // Determine if a new state should be entered.
        if (sc.state == SCE_ASY_DEFAULT) {
            if (setWordStart.Contains(sc.ch) || (sc.ch == '@')) {
                sc.SetState(SCE_ASY_IDENTIFIER);
            } else if (sc.Match('/', '*')) {
                sc.SetState(SCE_ASY_COMMENT);
                sc.Forward();   //
            } else if (sc.Match('/', '/')) {
                sc.SetState(SCE_ASY_COMMENTLINE);
            } else if (sc.ch == '\"') {
                sc.SetState(SCE_ASY_STRING);
            } else if (sc.ch == '\'') {
                sc.SetState(SCE_ASY_CHARACTER);
            } else if (sc.ch == '#' && visibleChars == 0) {
                do {
                    sc.Forward();
                } while ((sc.ch == ' ' || sc.ch == '\t') && sc.More());
                if (sc.atLineEnd) {
                    sc.SetState(SCE_ASY_DEFAULT);
                }
            } else if (isoperator(static_cast<char>(sc.ch))) {
                sc.SetState(SCE_ASY_OPERATOR);
            }
        }

    }
    sc.Complete();
}

static bool IsAsyCommentStyle(int style) {
    return style == SCE_ASY_COMMENT;
}


static inline bool isASYidentifier(int ch) {
    return
      ((ch >= 'a') && (ch <= 'z')) || ((ch >= 'A') && (ch <= 'Z')) ;
}

static int ParseASYWord(unsigned int pos, Accessor &styler, char *word)
{
  int length=0;
  char ch=styler.SafeGetCharAt(pos);
  *word=0;

  while(isASYidentifier(ch) && length<100){
          word[length]=ch;
          length++;
          ch=styler.SafeGetCharAt(pos+length);
  }
  word[length]=0;
  return length;
}

static bool IsASYDrawingLine(int line, Accessor &styler) {
    int pos = styler.LineStart(line);
    int eol_pos = styler.LineStart(line + 1) - 1;

    int startpos = pos;
    char buffer[100]="";

    while (startpos<eol_pos){
        char ch = styler[startpos];
        ParseASYWord(startpos,styler,buffer);
        bool drawcommands = strncmp(buffer,"draw",4)==0||
            strncmp(buffer,"pair",4)==0||strncmp(buffer,"label",5)==0;
        if (!drawcommands && ch!=' ') return false;
        else if (drawcommands) return true;
        startpos++;
    }
    return false;
}

static void FoldAsyDoc(unsigned int startPos, int length, int initStyle,
                       WordList *[], Accessor &styler) {
    bool foldComment = styler.GetPropertyInt("fold.comment") != 0;
    bool foldCompact = styler.GetPropertyInt("fold.compact", 1) != 0;
    bool foldAtElse = styler.GetPropertyInt("fold.at.else", 0) != 0;
    unsigned int endPos = startPos + length;
    int visibleChars = 0;
    int lineCurrent = styler.GetLine(startPos);
    int levelCurrent = SC_FOLDLEVELBASE;
    if (lineCurrent > 0)
        levelCurrent = styler.LevelAt(lineCurrent-1) >> 16;
    int levelMinCurrent = levelCurrent;
    int levelNext = levelCurrent;
    char chNext = styler[startPos];
    int styleNext = styler.StyleAt(startPos);
    int style = initStyle;
    for (unsigned int i = startPos; i < endPos; i++) {
        char ch = chNext;
        chNext = styler.SafeGetCharAt(i + 1);
        int stylePrev = style;
        style = styleNext;
        styleNext = styler.StyleAt(i + 1);
        bool atEOL = (ch == '\r' && chNext != '\n') || (ch == '\n');
        if (foldComment && IsAsyCommentStyle(style)) {
            if (!IsAsyCommentStyle(stylePrev) && (stylePrev != SCE_ASY_COMMENTLINEDOC)) {
                levelNext++;
            } else if (!IsAsyCommentStyle(styleNext) && (styleNext != SCE_ASY_COMMENTLINEDOC) && !atEOL) {
                levelNext--;
            }
        }
        if (style == SCE_ASY_OPERATOR) {
            if (ch == '{') {
                if (levelMinCurrent > levelNext) {
                    levelMinCurrent = levelNext;
                }
                levelNext++;
            } else if (ch == '}') {
                levelNext--;
            }
        }

        if (atEOL && IsASYDrawingLine(lineCurrent, styler)){
            if (lineCurrent==0 && IsASYDrawingLine(lineCurrent + 1, styler))
                levelNext++;
            else if (lineCurrent!=0 && !IsASYDrawingLine(lineCurrent - 1, styler)
                && IsASYDrawingLine(lineCurrent + 1, styler)
                )
                levelNext++;
            else if (lineCurrent!=0 && IsASYDrawingLine(lineCurrent - 1, styler) &&
                !IsASYDrawingLine(lineCurrent+1, styler))
                levelNext--;
        }

        if (atEOL) {
            int levelUse = levelCurrent;
            if (foldAtElse) {
                levelUse = levelMinCurrent;
            }
            int lev = levelUse | levelNext << 16;
            if (visibleChars == 0 && foldCompact)
                lev |= SC_FOLDLEVELWHITEFLAG;
            if (levelUse < levelNext)
                lev |= SC_FOLDLEVELHEADERFLAG;
            if (lev != styler.LevelAt(lineCurrent)) {
                styler.SetLevel(lineCurrent, lev);
            }
            lineCurrent++;
            levelCurrent = levelNext;
            levelMinCurrent = levelCurrent;
            visibleChars = 0;
        }
        if (!IsASpace(ch))
            visibleChars++;
    }
}

static const char * const asyWordLists[] = {
            "Primary keywords and identifiers",
            "Secondary keywords and identifiers",
            0,
        };

LexerModule lmASY(SCLEX_ASYMPTOTE, ColouriseAsyDoc, "asy", FoldAsyDoc, asyWordLists);
