// SciTE - Scintilla based Text Editor
/** @file LexAVE.cxx
 ** Lexer for Avenue.
 **
  ** Written by Alexey Yutkin <yutkin@geol.msu.ru>.
 **/
// Copyright 1998-2002 by Neil Hodgson <neilh@scintilla.org>
// 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 <ctype.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 IsEnumChar(const int ch) {
    return (ch < 0x80) && (isalnum(ch)|| ch == '_');
}
static inline bool IsANumberChar(const int ch) {
    return (ch < 0x80) && (isalnum(ch) || ch == '.' );
}

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

inline bool isAveOperator(char ch) {
    if (isascii(ch) && isalnum(ch))
        return false;
    // '.' left out as it is used to make up numbers
    if (ch == '*' || ch == '/' || ch == '-' || ch == '+' ||
        ch == '(' || ch == ')' || ch == '=' ||
        ch == '{' || ch == '}' ||
        ch == '[' || ch == ']' || ch == ';' ||
        ch == '<' || ch == '>' || ch == ',' ||
        ch == '.'  )
        return true;
    return false;
}

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

    WordList &keywords = *keywordlists[0];
    WordList &keywords2 = *keywordlists[1];
    WordList &keywords3 = *keywordlists[2];
    WordList &keywords4 = *keywordlists[3];
    WordList &keywords5 = *keywordlists[4];
    WordList &keywords6 = *keywordlists[5];

    // Do not leak onto next line
    if (initStyle == SCE_AVE_STRINGEOL) {
        initStyle = SCE_AVE_DEFAULT;
    }

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

    for (; sc.More(); sc.Forward()) {
        if (sc.atLineEnd) {
            // Update the line state, so it can be seen by next line
            int currentLine = styler.GetLine(sc.currentPos);
            styler.SetLineState(currentLine, 0);
        }
        if (sc.atLineStart && (sc.state == SCE_AVE_STRING)) {
            // Prevent SCE_AVE_STRINGEOL from leaking back to previous line
            sc.SetState(SCE_AVE_STRING);
        }


        // Determine if the current state should terminate.
        if (sc.state == SCE_AVE_OPERATOR) {
            sc.SetState(SCE_AVE_DEFAULT);
        } else if (sc.state == SCE_AVE_NUMBER) {
            if (!IsANumberChar(sc.ch)) {
                sc.SetState(SCE_AVE_DEFAULT);
            }
        } else if (sc.state == SCE_AVE_ENUM) {
            if (!IsEnumChar(sc.ch)) {
                sc.SetState(SCE_AVE_DEFAULT);
            }
        } else if (sc.state == SCE_AVE_IDENTIFIER) {
            if (!IsAWordChar(sc.ch) || (sc.ch == '.')) {
                char s[100];
                //sc.GetCurrent(s, sizeof(s));
                sc.GetCurrentLowered(s, sizeof(s));
                if (keywords.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD);
                } else if (keywords2.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD2);
                } else if (keywords3.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD3);
                } else if (keywords4.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD4);
                } else if (keywords5.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD5);
                } else if (keywords6.InList(s)) {
                    sc.ChangeState(SCE_AVE_WORD6);
                }
                sc.SetState(SCE_AVE_DEFAULT);
            }
        } else if (sc.state == SCE_AVE_COMMENT) {
            if (sc.atLineEnd) {
                sc.SetState(SCE_AVE_DEFAULT);
            }
        } else if (sc.state == SCE_AVE_STRING) {
             if (sc.ch == '\"') {
                sc.ForwardSetState(SCE_AVE_DEFAULT);
            } else if (sc.atLineEnd) {
                sc.ChangeState(SCE_AVE_STRINGEOL);
                sc.ForwardSetState(SCE_AVE_DEFAULT);
            }
        }

        // Determine if a new state should be entered.
        if (sc.state == SCE_AVE_DEFAULT) {
            if (IsADigit(sc.ch) || (sc.ch == '.' && IsADigit(sc.chNext))) {
                sc.SetState(SCE_AVE_NUMBER);
            } else if (IsAWordStart(sc.ch)) {
                sc.SetState(SCE_AVE_IDENTIFIER);
            } else if (sc.Match('\"')) {
                sc.SetState(SCE_AVE_STRING);
            } else if (sc.Match('\'')) {
                sc.SetState(SCE_AVE_COMMENT);
                sc.Forward();
            } else if (isAveOperator(static_cast<char>(sc.ch))) {
                sc.SetState(SCE_AVE_OPERATOR);
            } else if (sc.Match('#')) {
                sc.SetState(SCE_AVE_ENUM);
                sc.Forward();
            }
        }
    }
    sc.Complete();
}

static void FoldAveDoc(unsigned int startPos, int length, int /* initStyle */, WordList *[],
                       Accessor &styler) {
    unsigned int lengthDoc = startPos + length;
    int visibleChars = 0;
    int lineCurrent = styler.GetLine(startPos);
    int levelPrev = styler.LevelAt(lineCurrent) & SC_FOLDLEVELNUMBERMASK;
    int levelCurrent = levelPrev;
    char chNext = static_cast<char>(tolower(styler[startPos]));
    bool foldCompact = styler.GetPropertyInt("fold.compact", 1) != 0;
    int styleNext = styler.StyleAt(startPos);
    char s[10];

    for (unsigned int i = startPos; i < lengthDoc; i++) {
        char ch = static_cast<char>(tolower(chNext));
        chNext = static_cast<char>(tolower(styler.SafeGetCharAt(i + 1)));
        int style = styleNext;
        styleNext = styler.StyleAt(i + 1);
        bool atEOL = (ch == '\r' && chNext != '\n') || (ch == '\n');
        if (style == SCE_AVE_WORD) {
            if (ch == 't' || ch == 'f' || ch == 'w' || ch == 'e') {
                for (unsigned int j = 0; j < 6; j++) {
                    if (!iswordchar(styler[i + j])) {
                        break;
                    }
                    s[j] = static_cast<char>(tolower(styler[i + j]));
                    s[j + 1] = '\0';
                }

                if ((strcmp(s, "then") == 0) || (strcmp(s, "for") == 0) || (strcmp(s, "while") == 0)) {
                    levelCurrent++;
                }
                if ((strcmp(s, "end") == 0) || (strcmp(s, "elseif") == 0)) {
                    // Normally "elseif" and "then" will be on the same line and will cancel
                    // each other out.  // As implemented, this does not support fold.at.else.
                    levelCurrent--;
                }
            }
        } else if (style == SCE_AVE_OPERATOR) {
            if (ch == '{' || ch == '(') {
                levelCurrent++;
            } else if (ch == '}' || ch == ')') {
                levelCurrent--;
            }
        }

        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;
        }
        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);
}

LexerModule lmAVE(SCLEX_AVE, ColouriseAveDoc, "ave", FoldAveDoc);

