/*
 * Copyright 2016 WebAssembly Community Group participants
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef WASM_AST_LEXER_H_
#define WASM_AST_LEXER_H_

#include <stddef.h>
#include <stdio.h>

#include "common.h"
#include "vector.h"

struct WasmAllocator;

typedef enum WasmAstLexerSourceType {
  WASM_LEXER_SOURCE_TYPE_FILE,
  WASM_LEXER_SOURCE_TYPE_BUFFER,
} WasmAstLexerSourceType;

typedef struct WasmAstLexerSource {
  WasmAstLexerSourceType type;
  union {
    FILE* file;
    struct {
      const void* data;
      size_t size;
      size_t read_offset;
    } buffer;
  };
} WasmAstLexerSource;

typedef struct WasmAstLexer {
  struct WasmAllocator* allocator;
  WasmAstLexerSource source;
  const char* filename;
  int line;
  int comment_nesting;
  size_t buffer_file_offset; /* file offset of the start of the buffer */
  size_t line_file_offset;   /* file offset of the start of the current line */

  /* lexing data needed by re2c */
  WasmBool eof;
  char* buffer;
  size_t buffer_size;
  char* marker;
  char* token;
  char* cursor;
  char* limit;
} WasmAstLexer;

WASM_EXTERN_C_BEGIN

WasmAstLexer* wasm_new_ast_file_lexer(struct WasmAllocator*,
                                      const char* filename);
WasmAstLexer* wasm_new_ast_buffer_lexer(struct WasmAllocator*,
                                        const char* filename,
                                        const void* data,
                                        size_t size);
void wasm_destroy_ast_lexer(WasmAstLexer*);
WASM_EXTERN_C_END

#endif /* WASM_AST_LEXER_H_ */