// Scintilla source code edit control
/** @file LexSML.cxx
 ** Lexer for SML.
 **/
// Copyright 2009 by James Moffatt and Yuzhou Xin
// Modified from LexCaml.cxx by Robert Roessler <robertr@rftp.com> Copyright 2005
// 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"

inline int  issml(int c) {return isalnum(c) || c == '_';}
inline int issmlf(int c) {return isalpha(c) || c == '_';}
inline int issmld(int c) {return isdigit(c) || c == '_';}


#ifdef SCI_NAMESPACE
using namespace Scintilla;
#endif

void ColouriseSMLDoc(
    unsigned int startPos, int length,
    int initStyle,
    WordList *keywordlists[],
    Accessor &styler)
{
    StyleContext sc(startPos, length, initStyle, styler);
    int nesting = 0;
    if (sc.state < SCE_SML_STRING)
        sc.state = SCE_SML_DEFAULT;
    if (sc.state >= SCE_SML_COMMENT)
        nesting = (sc.state & 0x0f) - SCE_SML_COMMENT;

    int chBase = 0, chToken = 0, chLit = 0;
    WordList& keywords  = *keywordlists[0];
    WordList& keywords2 = *keywordlists[1];
    WordList& keywords3 = *keywordlists[2];
    const int useMagic = styler.GetPropertyInt("lexer.caml.magic", 0);

    while (sc.More()) {
        int state2 = -1;
        int chColor = sc.currentPos - 1;
        bool advance = true;

        switch (sc.state & 0x0f) {
        case SCE_SML_DEFAULT:
            chToken = sc.currentPos;
            if (issmlf(sc.ch))
                state2 = SCE_SML_IDENTIFIER;
            else if (sc.Match('`') && issmlf(sc.chNext))
                state2 = SCE_SML_TAGNAME;
            else if (sc.Match('#')&&isdigit(sc.chNext))
                    state2 = SCE_SML_LINENUM;
            else if (sc.Match('#','\"')){
                    state2 = SCE_SML_CHAR,chLit = 0;
                    sc.Forward();

                }
            else if (isdigit(sc.ch)) {
                state2 = SCE_SML_NUMBER, chBase = 10;
                if (sc.Match('0') && strchr("xX", sc.chNext))
                    chBase = 16, sc.Forward();}
            else if (sc.Match('\"')&&sc.chPrev!='#')
                state2 = SCE_SML_STRING;
            else if (sc.Match('(', '*')){
                state2 = SCE_SML_COMMENT,
                    sc.ch = ' ',
                    sc.Forward();}
            else if (strchr("!~"
                    "=<>@^+-*/"
                    "()[];,:.#", sc.ch))
                state2 = SCE_SML_OPERATOR;
            break;

        case SCE_SML_IDENTIFIER:
            if (!(issml(sc.ch) || sc.Match('\''))) {
                const int n = sc.currentPos - chToken;
                if (n < 24) {
                    char t[24];
                    for (int i = -n; i < 0; i++)
                        t[n + i] = static_cast<char>(sc.GetRelative(i));
                    t[n] = '\0';
                    if ((n == 1 && sc.chPrev == '_') || keywords.InList(t))
                        sc.ChangeState(SCE_SML_KEYWORD);
                    else if (keywords2.InList(t))
                        sc.ChangeState(SCE_SML_KEYWORD2);
                    else if (keywords3.InList(t))
                        sc.ChangeState(SCE_SML_KEYWORD3);
                }
                state2 = SCE_SML_DEFAULT, advance = false;
            }
            break;

        case SCE_SML_TAGNAME:
            if (!(issml(sc.ch) || sc.Match('\'')))
                state2 = SCE_SML_DEFAULT, advance = false;
            break;

        case SCE_SML_LINENUM:
            if (!isdigit(sc.ch))
                state2 = SCE_SML_DEFAULT, advance = false;
            break;

        case SCE_SML_OPERATOR: {
            const char* o = 0;
            if (issml(sc.ch) || isspace(sc.ch)
                || (o = strchr(")]};,\'\"`#", sc.ch),o)
                || !strchr("!$%&*+-./:<=>?@^|~", sc.ch)) {
                if (o && strchr(")]};,", sc.ch)) {
                    if ((sc.Match(')') && sc.chPrev == '(')
                        || (sc.Match(']') && sc.chPrev == '['))
                        sc.ChangeState(SCE_SML_KEYWORD);
                    chColor++;
                } else
                    advance = false;
                state2 = SCE_SML_DEFAULT;
            }
            break;
        }

        case SCE_SML_NUMBER:
            if (issmld(sc.ch) || IsADigit(sc.ch, chBase))
                break;
            if ((sc.Match('l') || sc.Match('L') || sc.Match('n'))
                && (issmld(sc.chPrev) || IsADigit(sc.chPrev, chBase)))
                break;
            if (chBase == 10) {
                if (sc.Match('.') && issmld(sc.chPrev))
                    break;
                if ((sc.Match('e') || sc.Match('E'))
                    && (issmld(sc.chPrev) || sc.chPrev == '.'))
                    break;
                if ((sc.Match('+') || sc.Match('-'))
                    && (sc.chPrev == 'e' || sc.chPrev == 'E'))
                    break;
            }
            state2 = SCE_SML_DEFAULT, advance = false;
            break;

        case SCE_SML_CHAR:
            if (sc.Match('\\')) {
                chLit = 1;
                if (sc.chPrev == '\\')
                    sc.ch = ' ';
            } else if ((sc.Match('\"') && sc.chPrev != '\\') || sc.atLineEnd) {
                state2 = SCE_SML_DEFAULT;
                chLit = 1;
                if (sc.Match('\"'))
                    chColor++;
                else
                    sc.ChangeState(SCE_SML_IDENTIFIER);
            } else if (chLit < 1 && sc.currentPos - chToken >= 3)
                sc.ChangeState(SCE_SML_IDENTIFIER), advance = false;
            break;

        case SCE_SML_STRING:
            if (sc.Match('\\') && sc.chPrev == '\\')
                sc.ch = ' ';
            else if (sc.Match('\"') && sc.chPrev != '\\')
                state2 = SCE_SML_DEFAULT, chColor++;
            break;

        case SCE_SML_COMMENT:
        case SCE_SML_COMMENT1:
        case SCE_SML_COMMENT2:
        case SCE_SML_COMMENT3:
            if (sc.Match('(', '*'))
                state2 = sc.state + 1, chToken = sc.currentPos,
                    sc.ch = ' ',
                    sc.Forward(), nesting++;
            else if (sc.Match(')') && sc.chPrev == '*') {
                if (nesting)
                    state2 = (sc.state & 0x0f) - 1, chToken = 0, nesting--;
                else
                    state2 = SCE_SML_DEFAULT;
                chColor++;
            } else if (useMagic && sc.currentPos - chToken == 4
                && sc.Match('c') && sc.chPrev == 'r' && sc.GetRelative(-2) == '@')
                sc.state |= 0x10;
            break;
        }

        if (state2 >= 0)
            styler.ColourTo(chColor, sc.state), sc.ChangeState(state2);
        if (advance)
            sc.Forward();
    }

    sc.Complete();
}

void FoldSMLDoc(
    unsigned int, int,
    int,
    WordList *[],
    Accessor &)
{
}

static const char * const SMLWordListDesc[] = {
    "Keywords",
    "Keywords2",
    "Keywords3",
    0
};

LexerModule lmSML(SCLEX_SML, ColouriseSMLDoc, "SML", FoldSMLDoc, SMLWordListDesc);

