/*
 * Copyright 2022 Olaf Wintermann
 *
 * Permission is hereby granted, free of charge, to any person obtaining a 
 * copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation 
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the 
 * Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in 
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
 * DEALINGS IN THE SOFTWARE.
 */

#ifndef JSON_H
#define JSON_H

#include <stdlib.h>
#include <inttypes.h>

#ifdef __cplusplus
extern "C" {
#endif

typedef struct JSONParser    JSONParser;
typedef struct JSONToken     JSONToken;

typedef struct JSONValue     JSONValue;

typedef enum JSONTokenType   JSONTokenType;
typedef enum JSONValueType   JSONValueType;
typedef enum JSONLiteralType JSONLiteralType;
typedef enum JSONReaderType  JSONReaderType;

typedef struct JSONArray JSONArray;
typedef struct JSONObject JSONObject;
typedef struct JSONString JSONString;
typedef struct JSONInteger JSONInteger;
typedef struct JSONNumber JSONNumber;
typedef struct JSONLiteral JSONLiteral;

typedef struct JSONObjValue JSONObjValue;

typedef struct JSONReadValueStack JSONReadValueStack;

enum JSONTokenType {
    JSON_NO_TOKEN = 0,
    JSON_TOKEN_ERROR,
    JSON_TOKEN_BEGIN_ARRAY,
    JSON_TOKEN_BEGIN_OBJECT,
    JSON_TOKEN_END_ARRAY,
    JSON_TOKEN_END_OBJECT,
    JSON_TOKEN_NAME_SEPARATOR,
    JSON_TOKEN_VALUE_SEPARATOR,
    JSON_TOKEN_STRING,
    JSON_TOKEN_INTEGER,
    JSON_TOKEN_NUMBER,
    JSON_TOKEN_LITERAL,
    JSON_TOKEN_SPACE
};

enum JSONValueType {
    JSON_OBJECT = 0,
    JSON_ARRAY,
    JSON_STRING,
    JSON_INTEGER,
    JSON_NUMBER,
    JSON_LITERAL
};

enum JSONLiteralType {
    JSON_NULL = 0,
    JSON_TRUE,
    JSON_FALSE
};

enum JSONReaderType {
    JSON_READER_OBJECT_BEGIN,
    JSON_READER_OBJECT_END,
    JSON_READER_ARRAY_BEGIN,
    JSON_READER_ARRAY_END,
    JSON_READER_STRING,
    JSON_READER_INTEGER,
    JSON_READER_NUMBER,
    JSON_READER_LITERAL
};

struct JSONToken {
    JSONTokenType tokentype;
    const char *content;
    size_t length;
    size_t alloc;
};

struct JSONParser {
    const char *buffer;
    size_t size;
    size_t pos;
    
    JSONToken uncompleted;
    int tokenizer_escape;
    
    int *states;
    int nstates;
    int states_alloc;
    
    JSONToken reader_token;
    JSONReaderType reader_type;
    int value_ready;
    char *value_name;
    size_t value_name_len;
    char *value_str;
    size_t value_str_len;
    int64_t value_int;
    double value_double;
    
    JSONValue **readvalue_stack;
    int readvalue_nelm;
    int readvalue_alloc;
    JSONValue *read_value;
    int readvalue_initialized;
    
    int reader_array_alloc;
    
    int error;
};

struct JSONArray {
    JSONValue **array;
    size_t alloc;
    size_t size;
};

struct JSONObject {
    JSONObjValue *values;
    size_t alloc;
    size_t size;
};

struct JSONObjValue {
    char *name;
    JSONValue *value;
};

struct JSONString {
    char *string;
    size_t length;
};

struct JSONInteger {
    int64_t value;
};

struct JSONNumber {
    double value;
};

struct JSONLiteral {
    JSONLiteralType literal;
};


struct JSONValue {
    JSONValueType type;
    union {
        JSONArray   array;
        JSONObject  object;
        JSONString  string;
        JSONInteger integer;
        JSONNumber  number;
        JSONLiteral literal;
    } value;
};


JSONParser* json_parser_new(void);
void json_parser_free(JSONParser *p);

void json_parser_fill(JSONParser *p, const char *buf, size_t size);

JSONToken json_parser_next_token(JSONParser *p);

int json_read(JSONParser *p);

JSONReaderType json_reader_type(JSONParser *p);
const char* json_reader_name(JSONParser *p, size_t *opt_len);
const char* json_reader_string(JSONParser *p, size_t *opt_len);
int64_t json_reader_int(JSONParser *p);
double json_reader_double(JSONParser *p);
int json_reader_isnull(JSONParser *p);
JSONLiteralType json_reader_literal(JSONParser *p);
int json_reader_bool(JSONParser *p);

int json_read_value(JSONParser *p, JSONValue **value);

JSONValue* json_obj_get(JSONObject *obj, const char *name);

JSONValue* json_array_get(JSONArray *array, size_t i);

void json_value_free(JSONValue *value);

int json_strcmp(JSONValue *jsstr, const char *str);
int json_strncmp(JSONValue *jsstr, const char *str, size_t slen);

#ifdef __cplusplus
}
#endif

#endif /* JSON_H */