// Scintilla source code edit control
/** @file LexESCRIPT.cxx
 ** Lexer for ESCRIPT
 **/
// Copyright 2003 by Patrizio Bekerle (patrizio@bekerle.com)

#include <stdlib.h>
#include <string.h>
#include <ctype.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 inline bool IsAWordChar(const int ch) {
    return (ch < 0x80) && (isalnum(ch) || ch == '.' || ch == '_');
}

static inline bool IsAWordStart(const int ch) {
    return (ch < 0x80) && (isalnum(ch) || ch == '_');
}



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

    WordList &keywords = *keywordlists[0];
    WordList &keywords2 = *keywordlists[1];
    WordList &keywords3 = *keywordlists[2];

    // Do not leak onto next line
    /*if (initStyle == SCE_ESCRIPT_STRINGEOL)
        initStyle = SCE_ESCRIPT_DEFAULT;*/

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

    bool caseSensitive = styler.GetPropertyInt("escript.case.sensitive", 0) != 0;

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

        /*if (sc.atLineStart && (sc.state == SCE_ESCRIPT_STRING)) {
            // Prevent SCE_ESCRIPT_STRINGEOL from leaking back to previous line
            sc.SetState(SCE_ESCRIPT_STRING);
        }*/

        // Handle line continuation generically.
        if (sc.ch == '\\') {
            if (sc.chNext == '\n' || sc.chNext == '\r') {
                sc.Forward();
                if (sc.ch == '\r' && sc.chNext == '\n') {
                    sc.Forward();
                }
                continue;
            }
        }

        // Determine if the current state should terminate.
        if (sc.state == SCE_ESCRIPT_OPERATOR || sc.state == SCE_ESCRIPT_BRACE) {
            sc.SetState(SCE_ESCRIPT_DEFAULT);
        } else if (sc.state == SCE_ESCRIPT_NUMBER) {
            if (!IsADigit(sc.ch) || sc.ch != '.') {
                sc.SetState(SCE_ESCRIPT_DEFAULT);
            }
        } else if (sc.state == SCE_ESCRIPT_IDENTIFIER) {
            if (!IsAWordChar(sc.ch) || (sc.ch == '.')) {
                char s[100];
                if (caseSensitive) {
                    sc.GetCurrent(s, sizeof(s));
                } else {
                    sc.GetCurrentLowered(s, sizeof(s));
                }

//              sc.GetCurrentLowered(s, sizeof(s));

                                if (keywords.InList(s)) {
                    sc.ChangeState(SCE_ESCRIPT_WORD);
                } else if (keywords2.InList(s)) {
                    sc.ChangeState(SCE_ESCRIPT_WORD2);
                } else if (keywords3.InList(s)) {
                    sc.ChangeState(SCE_ESCRIPT_WORD3);
                                        // sc.state = SCE_ESCRIPT_IDENTIFIER;
                }
                sc.SetState(SCE_ESCRIPT_DEFAULT);
            }
        } else if (sc.state == SCE_ESCRIPT_COMMENT) {
            if (sc.Match('*', '/')) {
                sc.Forward();
                sc.ForwardSetState(SCE_ESCRIPT_DEFAULT);
            }
        } else if (sc.state == SCE_ESCRIPT_COMMENTDOC) {
            if (sc.Match('*', '/')) {
                sc.Forward();
                sc.ForwardSetState(SCE_ESCRIPT_DEFAULT);
            }
        } else if (sc.state == SCE_ESCRIPT_COMMENTLINE) {
            if (sc.atLineEnd) {
                sc.SetState(SCE_ESCRIPT_DEFAULT);
            }
        } else if (sc.state == SCE_ESCRIPT_STRING) {
            if (sc.ch == '\\') {
                if (sc.chNext == '\"' || sc.chNext == '\\') {
                    sc.Forward();
                }
            } else if (sc.ch == '\"') {
                sc.ForwardSetState(SCE_ESCRIPT_DEFAULT);
            }
        }

        // Determine if a new state should be entered.
        if (sc.state == SCE_ESCRIPT_DEFAULT) {
            if (IsADigit(sc.ch) || (sc.ch == '.' && IsADigit(sc.chNext))) {
                sc.SetState(SCE_ESCRIPT_NUMBER);
            } else if (IsAWordStart(sc.ch) || (sc.ch == '#')) {
                sc.SetState(SCE_ESCRIPT_IDENTIFIER);
            } else if (sc.Match('/', '*')) {
                sc.SetState(SCE_ESCRIPT_COMMENT);
                sc.Forward();   // Eat the * so it isn't used for the end of the comment
            } else if (sc.Match('/', '/')) {
                sc.SetState(SCE_ESCRIPT_COMMENTLINE);
            } else if (sc.ch == '\"') {
                sc.SetState(SCE_ESCRIPT_STRING);
                //} else if (isoperator(static_cast<char>(sc.ch))) {
            } else if (sc.ch == '+' || sc.ch == '-' || sc.ch == '*' || sc.ch == '/' || sc.ch == '=' || sc.ch == '<' || sc.ch == '>' || sc.ch == '&' || sc.ch == '|' || sc.ch == '!' || sc.ch == '?' || sc.ch == ':') {
                sc.SetState(SCE_ESCRIPT_OPERATOR);
            } else if (sc.ch == '{' || sc.ch == '}') {
                sc.SetState(SCE_ESCRIPT_BRACE);
            }
        }

    }
    sc.Complete();
}


static int classifyFoldPointESCRIPT(const char* s, const char* prevWord) {
    int lev = 0;
    if (strcmp(prevWord, "end") == 0) return lev;
    if ((strcmp(prevWord, "else") == 0 && strcmp(s, "if") == 0) || strcmp(s, "elseif") == 0)
        return -1;

        if (strcmp(s, "for") == 0 || strcmp(s, "foreach") == 0
        || strcmp(s, "program") == 0 || strcmp(s, "function") == 0
        || strcmp(s, "while") == 0 || strcmp(s, "case") == 0
        || strcmp(s, "if") == 0 ) {
        lev = 1;
    } else if ( strcmp(s, "endfor") == 0 || strcmp(s, "endforeach") == 0
        || strcmp(s, "endprogram") == 0 || strcmp(s, "endfunction") == 0
        || strcmp(s, "endwhile") == 0 || strcmp(s, "endcase") == 0
        || strcmp(s, "endif") == 0 ) {
        lev = -1;
    }

    return lev;
}


static bool IsStreamCommentStyle(int style) {
    return style == SCE_ESCRIPT_COMMENT ||
           style == SCE_ESCRIPT_COMMENTDOC ||
           style == SCE_ESCRIPT_COMMENTLINE;
}

static void FoldESCRIPTDoc(unsigned int startPos, int length, int initStyle, WordList *[], Accessor &styler) {
    //~ bool foldComment = styler.GetPropertyInt("fold.comment") != 0;
    // Do not know how to fold the comment at the moment.
    bool foldCompact = styler.GetPropertyInt("fold.compact", 1) != 0;
        bool foldComment = true;
    unsigned int endPos = startPos + length;
    int visibleChars = 0;
    int lineCurrent = styler.GetLine(startPos);
    int levelPrev = styler.LevelAt(lineCurrent) & SC_FOLDLEVELNUMBERMASK;
    int levelCurrent = levelPrev;
    char chNext = styler[startPos];
    int styleNext = styler.StyleAt(startPos);
    int style = initStyle;

    int lastStart = 0;
    char prevWord[32] = "";

    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 && IsStreamCommentStyle(style)) {
            if (!IsStreamCommentStyle(stylePrev)) {
                levelCurrent++;
            } else if (!IsStreamCommentStyle(styleNext) && !atEOL) {
                // Comments don't end at end of line and the next character may be unstyled.
                levelCurrent--;
            }
        }

        if (foldComment && (style == SCE_ESCRIPT_COMMENTLINE)) {
            if ((ch == '/') && (chNext == '/')) {
                char chNext2 = styler.SafeGetCharAt(i + 2);
                if (chNext2 == '{') {
                    levelCurrent++;
                } else if (chNext2 == '}') {
                    levelCurrent--;
                }
            }
        }

        if (stylePrev == SCE_ESCRIPT_DEFAULT && style == SCE_ESCRIPT_WORD3)
        {
            // Store last word start point.
            lastStart = i;
        }

        if (style == SCE_ESCRIPT_WORD3) {
            if(iswordchar(ch) && !iswordchar(chNext)) {
                char s[32];
                unsigned int j;
                for(j = 0; ( j < 31 ) && ( j < i-lastStart+1 ); j++) {
                    s[j] = static_cast<char>(tolower(styler[lastStart + j]));
                }
                s[j] = '\0';
                levelCurrent += classifyFoldPointESCRIPT(s, prevWord);
                strcpy(prevWord, s);
            }
        }
        if (atEOL) {
            int lev = levelPrev;
            if (visibleChars == 0 && foldCompact)
                lev |= SC_FOLDLEVELWHITEFLAG;
            if ((levelCurrent > levelPrev) && (visibleChars > 0))
                lev |= SC_FOLDLEVELHEADERFLAG;
            if (lev != styler.LevelAt(lineCurrent)) {
                styler.SetLevel(lineCurrent, lev);
            }
            lineCurrent++;
            levelPrev = levelCurrent;
            visibleChars = 0;
            strcpy(prevWord, "");
        }

        if (!isspacechar(ch))
            visibleChars++;
    }

    // Fill in the real level of the next line, keeping the current flags as they will be filled in later
    int flagsNext = styler.LevelAt(lineCurrent) & ~SC_FOLDLEVELNUMBERMASK;
    styler.SetLevel(lineCurrent, levelPrev | flagsNext);
}



static const char * const ESCRIPTWordLists[] = {
    "Primary keywords and identifiers",
    "Intrinsic functions",
    "Extended and user defined functions",
    0,
};

LexerModule lmESCRIPT(SCLEX_ESCRIPT, ColouriseESCRIPTDoc, "escript", FoldESCRIPTDoc, ESCRIPTWordLists);
