/*

* This file is part of Espruino, a JavaScript interpreter for Microcontrollers

*

* Copyright (C) 2013 Gordon Williams <gw@pur3.co.uk>

*

* This Source Code Form is subject to the terms of the Mozilla Public

* License, v. 2.0. If a copy of the MPL was not distributed with this

* file, You can obtain one at http://mozilla.org/MPL/2.0/.

*

* ----------------------------------------------------------------------------

* Lexer (convert JsVar strings into a series of tokens)

* ----------------------------------------------------------------------------

*/

#ifndef JSLEX_H_

#define JSLEX_H_

#include "jsutils.h"

#include "jsvar.h"

#include "jsvariterator.h"

typedef enum LEX_TYPES {

LEX_EOF = 0,

LEX_ID = 256,

LEX_INT,

LEX_FLOAT,

LEX_STR,

LEX_UNFINISHED_STR,

LEX_UNFINISHED_COMMENT,

LEX_EQUAL,

LEX_TYPEEQUAL,

LEX_NEQUAL,

LEX_NTYPEEQUAL,

LEX_LEQUAL,

LEX_LSHIFT,

LEX_LSHIFTEQUAL,

LEX_GEQUAL,

LEX_RSHIFT,

LEX_RSHIFTUNSIGNED,

LEX_RSHIFTEQUAL,

LEX_RSHIFTUNSIGNEDEQUAL,

LEX_PLUSEQUAL,

LEX_MINUSEQUAL,

LEX_PLUSPLUS,

LEX_MINUSMINUS,

LEX_MULEQUAL,

LEX_DIVEQUAL,

LEX_MODEQUAL,

LEX_ANDEQUAL,

LEX_ANDAND,

LEX_OREQUAL,

LEX_OROR,

LEX_XOREQUAL,

// reserved words

#define LEX_R_LIST_START LEX_R_IF

LEX_R_IF,

LEX_R_ELSE,

LEX_R_DO,

LEX_R_WHILE,

LEX_R_FOR,

LEX_R_BREAK,

LEX_R_CONTINUE,

LEX_R_FUNCTION,

LEX_R_RETURN,

LEX_R_VAR,

LEX_R_THIS,

LEX_R_THROW,

LEX_R_TRY,

LEX_R_CATCH,

LEX_R_FINALLY,

LEX_R_TRUE,

LEX_R_FALSE,

LEX_R_NULL,

LEX_R_UNDEFINED,

LEX_R_NEW,

LEX_R_IN,

LEX_R_INSTANCEOF,

LEX_R_SWITCH,

LEX_R_CASE,

LEX_R_DEFAULT,

LEX_R_DELETE,

LEX_R_TYPEOF,

LEX_R_VOID,

LEX_R_DEBUGGER,

LEX_R_LIST_END /* always the last entry */

} LEX_TYPES;

typedef struct JslCharPos {

JsvStringIterator it;

char currCh;

} JslCharPos;

void jslCharPosFree(JslCharPos *pos);

JslCharPos jslCharPosClone(JslCharPos *pos);

typedef struct JsLex

{

// Actual Lexing related stuff

char currCh;

short tk; ///< The type of the token that we have

JslCharPos tokenStart; ///< Position in the data at the beginning of the token we have here

size_t tokenLastStart; ///< Position in the data of the first character of the last token

char token[JSLEX_MAX_TOKEN_LENGTH]; ///< Data contained in the token we have here

JsVar *tokenValue; ///< JsVar containing the current token - used only for strings

unsigned char tokenl; ///< the current length of token

/** Amount we add to the line number when we're reporting to the user

* 1-based, so 0 means NO LINE NUMBER KNOWN */

uint16_t lineNumberOffset;

/* Where we get our data from...

*

* This is a bit more tricky than normal because the data comes from JsVars,

* which only have fixed length strings. If we go past this, we have to go

* to the next jsVar...

*/

JsVar *sourceVar; // the actual string var

JsvStringIterator it; // Iterator for the string

} JsLex;

// The lexer

extern JsLex *lex;

/// Set the lexer - return the old one

JsLex *jslSetLex(JsLex *l);

void jslInit(JsVar *var);

void jslKill();

void jslReset();

void jslSeekTo(size_t seekToChar);

void jslSeekToP(JslCharPos *seekToChar);

bool jslMatch(int expected_tk); ///< Match, and return true on success, false on failure

void jslTokenAsString(int token, char *str, size_t len); ///< output the given token as a string - for debugging

void jslGetTokenString(char *str, size_t len);

char *jslGetTokenValueAsString();

int jslGetTokenLength();

JsVar *jslGetTokenValueAsVar();

bool jslIsIDOrReservedWord();

// Only for more 'internal' use

void jslSeek(JslCharPos seekToChar); // like jslSeekTo, but doesn't pre-fill characters

void jslGetNextToken(); ///< Get the text token from our text string

JsVar *jslNewFromLexer(JslCharPos *charFrom, size_t charTo); // Create a new STRING from part of the lexer

/// Return the line number at the current character position (this isn't fast as it searches the string)

unsigned int jslGetLineNumber();

/// Print position in the form 'line X col Y'

void jslPrintPosition(vcbprintf_callback user_callback, void *user_data, size_t tokenPos);

/** Print the line of source code at `tokenPos`, prefixed with the string 'prefix' (0=no string).

* Then, underneath it, print a '^' marker at the column tokenPos was at */

void jslPrintTokenLineMarker(vcbprintf_callback user_callback, void *user_data, size_t tokenPos, char *prefix);

#endif /* JSLEX_H_ */