/*
 * 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.
 */

#include <stdio.h>
#include <string.h>
#include <ctype.h>

#include "json.h"

/*
 * RFC 8259
 * https://tools.ietf.org/html/rfc8259
 */

#define PARSER_STATES_ALLOC 32

JSONParser* json_parser_new(void) {
    JSONParser *parser = calloc(1, sizeof(JSONParser));
    if(!parser) {
        return NULL;
    }
    
    parser->states_alloc = PARSER_STATES_ALLOC;
    parser->states = calloc(PARSER_STATES_ALLOC, sizeof(int));
    if(!parser->states) {
        free(parser);
        return NULL;
    }
    
    parser->reader_array_alloc = 8;
    
    return parser;
}

void json_parser_free(JSONParser *p) {
    if(p->states) free(p->states);
    if(p->readvalue_stack) free(p->readvalue_stack);
    
    free(p);
}

void json_parser_fill(JSONParser *p, const char *buf, size_t size) {
    p->buffer = buf;
    p->size = size;
    p->pos = 0;
}


static JSONToken nulltoken = { JSON_NO_TOKEN, NULL, 0, 0 };

int token_append(JSONToken *token, const char *buf, size_t len) {
    if(len == 0) {
        return 0;
    }
    
    size_t newlen = token->length + len;
    if(token->alloc < newlen) {
        char *newbuf = realloc(
                token->alloc == 0 ? NULL : (char*)token->content,
                newlen);
        if(!newbuf) {
            return 1;
        }
        token->content = newbuf;
        token->alloc = newlen;
    }
    
    memcpy((char*)token->content+token->length, buf, len);
    token->length = newlen;
    return 0;
}

JSONToken get_content(JSONParser *p, size_t start, size_t end) {
    JSONToken token = nulltoken;
    size_t part2 = end - start;
    if(p->uncompleted.tokentype == JSON_NO_TOKEN) {
        token.content = p->buffer + start;
        token.length = part2;
    } else if(part2 == 0) {
        token = p->uncompleted;
    } else {
        if(token_append(&p->uncompleted, p->buffer+start, end - start)) {
            return nulltoken;
        }
        token = p->uncompleted;
    }
    p->uncompleted = nulltoken;
    return token;
}

int token_isliteral(const char *content, size_t length) {
    if(length == 4) {
        if(!memcmp(content, "true", 4)) {
            return 1;
        } else if(!memcmp(content, "null", 4)) {
            return 1;
        }
    } else if(length == 5 && !memcmp(content, "false", 5)) {
        return 1;
    }
    return 0;
}

static int num_isexp(const char *content, size_t length, size_t pos) {
    if(pos >= length) {
        return 0;
    }
    
    int ok = 0;
    for(size_t i=pos;i<length;i++) {
        int c = content[i];
        if(isdigit(c)) {
            ok = 1;
        } else if(i == pos) {
            if(!(c == '+' || c == '-')) {
                return 0;
            }
        } else {
            return 0;
        }
    }
    
    return ok;
}

JSONTokenType token_numbertype(const char *content, size_t length) {
    if(length == 0) return JSON_TOKEN_ERROR;
    
    if(content[0] != '-' && !isdigit(content[0])) {
        return JSON_TOKEN_ERROR;
    }
    
    JSONTokenType type = JSON_TOKEN_INTEGER;
    for(size_t i=1;i<length;i++) {
        if(content[i] == '.') {
            if(type == JSON_TOKEN_NUMBER) {
                return JSON_TOKEN_ERROR; // more than one decimal separator
            }
            type = JSON_TOKEN_NUMBER;
        } else if(content[i] == 'e' || content[i] == 'E') {
            return num_isexp(content, length, i+1) ? JSON_TOKEN_NUMBER : JSON_TOKEN_ERROR;
        } else if(!isdigit(content[i])) {
            return JSON_TOKEN_ERROR; // char is not a diget, decimal separator or exponent sep
        }
    }
    
    return type;
}

JSONToken get_token(JSONParser *p, size_t start, size_t end) {
    JSONToken token = get_content(p, start, end);
    if(token_isliteral(token.content, token.length)) {
        token.tokentype = JSON_TOKEN_LITERAL;
    } else {
        token.tokentype = token_numbertype(token.content, token.length);
    } 
    p->pos = end;
    return token;
}

static JSONTokenType char2ttype(char c) {
    switch(c) {
        case '[': {
            return JSON_TOKEN_BEGIN_ARRAY;
        }
        case '{': {
            return JSON_TOKEN_BEGIN_OBJECT;
        }
        case ']': {
            return JSON_TOKEN_END_ARRAY;
        }
        case '}': {
            return JSON_TOKEN_END_OBJECT;
        }
        case ':': {
            return JSON_TOKEN_NAME_SEPARATOR;
        }
        case ',': {
            return JSON_TOKEN_VALUE_SEPARATOR;
        }
        case '"': {
            return JSON_TOKEN_STRING;
        }
        default: {
            if(isspace(c)) {
                return JSON_TOKEN_SPACE;
            }
        }
    }
    return JSON_NO_TOKEN;
}

JSONToken json_parser_next_token(JSONParser *p) { 
    // current token type and start index
    JSONTokenType ttype = p->uncompleted.tokentype;
    size_t token_start = p->pos;
    
    for(size_t i=p->pos;i<p->size;i++) {
        char c = p->buffer[i];
        if(ttype != JSON_TOKEN_STRING) {
            // currently non-string token
            
            JSONTokenType ctype = char2ttype(c); // start of new token?
            
            if(ttype == JSON_NO_TOKEN) {
                if(ctype == JSON_TOKEN_SPACE) {
                    continue;
                } else if(ctype == JSON_TOKEN_STRING) {
                    // begin string
                    ttype = JSON_TOKEN_STRING;
                    token_start = i;
                } else if(ctype != JSON_NO_TOKEN) {
                    // single-char token
                    p->pos = i + 1;
                    JSONToken token = {  ctype, NULL, 0, 0};
                    return token;
                } else {
                    ttype = JSON_TOKEN_LITERAL; // number or literal
                    token_start = i;
                }
            } else {
                // finish token
                if(ctype != JSON_NO_TOKEN) {
                    return get_token(p, token_start, i);
                }
            }
        } else {
            // currently inside a string
            if(!p->tokenizer_escape) {
                if(c == '"') {
                    JSONToken ret = get_content(p, token_start, i+1);
                    ret.tokentype = JSON_TOKEN_STRING;
                    p->pos = i+1;
                    return ret;
                } else if(c == '\\') {
                    p->tokenizer_escape = 1;
                }
            } else {
                p->tokenizer_escape = 0;
            }
        }
    }
    
    if(ttype != JSON_NO_TOKEN) {
        // uncompleted token
        size_t uncompeted_len = p->size - token_start;
        if(p->uncompleted.tokentype == JSON_NO_TOKEN) {
            // current token is uncompleted
            // save current token content in p->uncompleted
            JSONToken uncompleted;
            uncompleted.tokentype = ttype;
            uncompleted.length = uncompeted_len;
            uncompleted.alloc = uncompeted_len + 16;
            char *tmp = malloc(uncompleted.alloc);
            if(tmp) {
                memcpy(tmp, p->buffer+token_start, uncompeted_len);
                uncompleted.content = tmp;
                p->uncompleted = uncompleted;
            } else {
                p->error = 1;
            }
        } else {
            // previously we also had an uncompleted token
            // combine the uncompleted token with the current token
            if(token_append(&p->uncompleted, p->buffer+token_start, uncompeted_len)) {
                p->error = 1;
            }
        }
    }
    
    JSONToken ret = { JSON_NO_TOKEN, NULL, 0, 0};
    return ret;
}

static int create_string(JSONToken token, JSONValue **value) {
    JSONValue *v = malloc(sizeof(JSONValue));
    if(!v) {
        *value = NULL;
        return -1;
    }
    v->type = JSON_STRING;
    
    char *str = malloc(token.length+1);
    if(!str) {
        free(v);
        *value = NULL;
        return -1;
    }
    memcpy(str, token.content, token.length);
    str[token.length] = 0;
    
    v->type = JSON_STRING;
    v->value.string.string = str;
    v->value.string.length = token.length;
    *value = v;
    return 0;
}

typedef struct json_ustr {
    char *ptr;
    size_t length;
} json_ustr;
static json_ustr unescape_string(const char *str, size_t len) {
    char *newstr = malloc(len+1);
    if(!newstr) {
        json_ustr r;
        r.ptr = NULL;
        r.length = 0;
        return r;
    }
    
    int j = 0;
    int u = 0;
    for(int i=1;i<len-1;i++) {
        char c = str[i];
        if(!u) {
            if(c == '\\') {
                u = 1;
            } else {
                newstr[j++] = c;
            }
        } else {
            u = 0;
            if(c == 'n') {
                c = '\n';
            } else if(c == 't') {
                c = '\t';
            }
            newstr[j++] = c;
        }
    }
    newstr[j] = 0;
    
    json_ustr r;
    r.ptr = newstr;
    r.length = j;
    return r;
}

static int parse_integer(const char *str, size_t len, int64_t *value) {
    char *endptr = NULL;
    char buf[32];
    if(len > 30) {
        return 1;
    }
    memcpy(buf, str, len);
    buf[len] = 0;
    
    long long v = strtoll(buf, &endptr, 10);
    if(endptr != &buf[len]) {
        return 1;
    }
    *value = (int64_t)v;
    
    return 0;
}

static int parse_number(const char *str, size_t len, double *value) {
    char *endptr = NULL;
    char buf[32];
    if(len > 30) {
        return 1;
    }
    memcpy(buf, str, len);
    buf[len] = 0;
    
    double v = strtod(buf, &endptr);
    if(endptr != &buf[len]) {
        return 1;
    }
    *value = v;
    
    return 0;
}

static int add_state(JSONParser *p, int state) {
    if(p->nstates >= p->states_alloc) {
        p->states_alloc += PARSER_STATES_ALLOC;
        p->states = realloc(p->states, p->states_alloc * sizeof(int));
        if(!p->states) {
            return 1;
        }
    }
    p->states[++p->nstates] = state;
    return 0;
}

static void end_elm(JSONParser *p, JSONReaderType type) {
    p->reader_type = type;
    p->nstates--;
}

#define JP_STATE_VALUE_BEGIN        0
#define JP_STATE_VALUE_BEGIN_OBJ    1
#define JP_STATE_VALUE_BEGIN_AR     2
#define JP_STATE_ARRAY_SEP_OR_CLOSE 3
#define JP_STATE_OBJ_NAME_OR_CLOSE  4
#define JP_STATE_OBJ_NAME           5
#define JP_STATE_OBJ_COLON          6
#define JP_STATE_OBJ_SEP_OR_CLOSE   7

static int next_state_after_value(int current) {
    switch(current) {
        default: return -1;
        // after value JSON complete, expect nothing
        case JP_STATE_VALUE_BEGIN: return -1; 
        // after obj value, expect ',' or '}'
        case JP_STATE_VALUE_BEGIN_OBJ: return JP_STATE_OBJ_SEP_OR_CLOSE;
        // after array value, expect ',' or ']'
        case JP_STATE_VALUE_BEGIN_AR: return JP_STATE_ARRAY_SEP_OR_CLOSE;
    }
}

static void clear_valuename(JSONParser *p) {
    if(p->value_name) free(p->value_name);
    p->value_name = NULL;
    p->value_name_len = 0;
}

static void clear_values(JSONParser *p) {
    if(p->value_str) free(p->value_str);
    p->value_str = NULL;
    p->value_str_len = 0;
    p->value_int = 0;
    p->value_double = 0;
}

int json_read(JSONParser *p) {
    int state = p->states[p->nstates];
    clear_values(p);
    JSONToken token = json_parser_next_token(p);
    p->reader_token = token;

    
    p->value_ready = 0;
    
    if(token.tokentype == JSON_NO_TOKEN) {
        return 0;
    }
    
    int ret = 1;
    
    // 0 JP_STATE_VALUE_BEGIN          value begin
    // 1 JP_STATE_VALUE_BEGIN_OBJ      value begin (inside object)
    // 2 JP_STATE_VALUE_BEGIN_AR       value begin (inside array)
    // 3 JP_STATE_ARRAY_SEP_OR_CLOSE   array, expect separator or arrayclose
    // 4 JP_STATE_OBJ_NAME_OR_CLOSE    object, expect name or objclose
    // 5 JP_STATE_OBJ_NAME             object, expect name
    // 6 JP_STATE_OBJ_COLON            object, expect ':'
    // 7 JP_STATE_OBJ_SEP_OR_CLOSE     object, expect separator, objclose
    
    if(state == JP_STATE_VALUE_BEGIN_AR || state == JP_STATE_OBJ_SEP_OR_CLOSE) {
        clear_valuename(p);
    }
    
    if(state < 3) {
        // expect value
        p->states[p->nstates] = next_state_after_value(state);
        p->value_ready = 1;
        switch(token.tokentype) {
            case JSON_TOKEN_BEGIN_ARRAY: {
                p->reader_type = JSON_READER_ARRAY_BEGIN;
                if(add_state(p, JP_STATE_VALUE_BEGIN_AR)) return -1;
                return 1;
                //return json_read(p);
            }
            case JSON_TOKEN_BEGIN_OBJECT: {
                p->reader_type = JSON_READER_OBJECT_BEGIN;
                if(add_state(p, JP_STATE_OBJ_NAME_OR_CLOSE)) return -1;
                return 1;
                //return json_read(p);
            }
            case JSON_TOKEN_END_ARRAY: {
                p->value_ready = 0;
                end_elm(p, JSON_READER_ARRAY_END);
                break;
            }
            case JSON_TOKEN_END_OBJECT: {
                p->value_ready = 0;
                end_elm(p, JSON_READER_OBJECT_END);
                break;
            }
            case JSON_TOKEN_STRING: {
                p->reader_type = JSON_READER_STRING;
                json_ustr str = unescape_string(token.content, token.length);
                if(str.ptr) {
                    p->value_str = str.ptr;
                    p->value_str_len = str.length;
                } else {
                    return -1;
                }
                break;
            }
            case JSON_TOKEN_INTEGER: {
                p->reader_type = JSON_READER_INTEGER;
                int64_t value;
                if(parse_integer(token.content, token.length, &value)) {
                    return -1;
                }
                p->value_int = value;
                p->value_double = (double)value;
                break;
            }
            case JSON_TOKEN_NUMBER: {
                p->reader_type = JSON_READER_NUMBER;
                double value;
                if(parse_number(token.content, token.length, &value)) {
                    return -1;
                }
                p->value_double = value;
                p->value_int = (int64_t)value;
                break;
            }
            case JSON_TOKEN_LITERAL: {
                p->reader_type = JSON_READER_LITERAL;
                break;
            }
            default: return -1;
        }
    } else if(state == JP_STATE_ARRAY_SEP_OR_CLOSE) {
        // expect ',' or ']'
        if(token.tokentype == JSON_TOKEN_VALUE_SEPARATOR) {
            p->states[p->nstates] = JP_STATE_VALUE_BEGIN_AR;
            return json_read(p);
        } else if(token.tokentype == JSON_TOKEN_END_ARRAY) {
            end_elm(p, JSON_READER_ARRAY_END);
        } else {
            return -1;
        }
    } else if(state == JP_STATE_OBJ_NAME_OR_CLOSE || state == JP_STATE_OBJ_NAME) {
        if(state == JP_STATE_OBJ_NAME_OR_CLOSE && token.tokentype == JSON_TOKEN_END_OBJECT) {
            clear_valuename(p);
            end_elm(p, JSON_READER_OBJECT_END);
        } else {
            // expect string
            if(token.tokentype != JSON_TOKEN_STRING) return -1;

            if(p->value_name) free(p->value_name);
            json_ustr valname = unescape_string(token.content, token.length);
            p->value_name = valname.ptr;
            p->value_name_len = valname.length;

            // next state
            p->states[p->nstates] = JP_STATE_OBJ_COLON;
            return json_read(p);
        }
    } else if(state == JP_STATE_OBJ_COLON) {
        // expect ':'
        if(token.tokentype != JSON_TOKEN_NAME_SEPARATOR) return -1;
        // next state
        p->states[p->nstates] = 1;
        return json_read(p);
    } else if(state == 7) {
        // expect ',' or '}]'
        if(token.tokentype == JSON_TOKEN_VALUE_SEPARATOR) {
            p->states[p->nstates] = JP_STATE_OBJ_NAME;
            return json_read(p);
        } else if(token.tokentype == JSON_TOKEN_END_OBJECT) {
            end_elm(p, JSON_READER_OBJECT_END);
        } else {
            return -1;
        }
    }
    
    return ret;
}


JSONReaderType json_reader_type(JSONParser *p) {
    return p->reader_type;
}

const char* json_reader_name(JSONParser *p, size_t *opt_len) {
    if(opt_len) *opt_len = p->value_name_len;
    return p->value_name;
}

const char* json_reader_string(JSONParser *p, size_t *opt_len) {
    if(opt_len) *opt_len = p->value_str_len;
    
    if(p->reader_token.tokentype != JSON_TOKEN_STRING) {
        return NULL;
    }
    
    return p->value_str;
}

int64_t json_reader_int(JSONParser *p) {
    return p->value_int;
}

double json_reader_double(JSONParser *p) {
    return p->value_double;
}

int json_reader_isnull(JSONParser *p) {
    if(p->reader_token.tokentype == JSON_TOKEN_LITERAL && p->reader_token.length == 4) {
        return !memcmp(p->reader_token.content, "null", 4);
    }
    return 0;
}

JSONLiteralType json_reader_literal(JSONParser *p) {
    const char *l = p->reader_token.content;
    size_t token_len = p->reader_token.length;
    if(token_len == 4 && !memcmp(l, "true", 4)) {
        return JSON_TRUE;
    } else if(token_len == 5 && !memcmp(l, "false", 5)) {
        return JSON_FALSE;
    }
    return JSON_NULL;
}

int json_reader_bool(JSONParser *p) {
    JSONLiteralType lt = json_reader_literal(p);
    return lt == JSON_TRUE ? 1 : 0;
}


/* -------------------- read value functions -------------------- */

static JSONValue* init_value(JSONParser *p) {
    JSONValue *value = malloc(sizeof(JSONValue));
    if(!value) {
        return NULL;
    }
    memset(value, 0, sizeof(JSONValue));
    return value;
}

static int setup_read_value(JSONParser *p) {
    p->readvalue_alloc = PARSER_STATES_ALLOC;
    p->readvalue_nelm = 0;
    p->readvalue_stack = calloc(PARSER_STATES_ALLOC, sizeof(JSONValue*));
    if(!p->readvalue_stack) return -1;
    
    p->read_value = NULL;
    p->readvalue_stack[0] = NULL;
    
    return 0;
}

static int obj_init_values(JSONParser *p, JSONValue *v) {  
    v->value.object.values = calloc(sizeof(JSONObjValue), p->reader_array_alloc);
    if(!v->value.object.values) {
        return -1;
    }
    v->value.object.alloc = p->reader_array_alloc;
    v->value.object.size = 0;
    
    return 0;
}

static int obj_add_value(JSONParser *p, JSONValue *parent, JSONObjValue v) {
    if(!parent->value.object.values) {
        if(obj_init_values(p, parent)) {
            return -1;
        }
    }
    
    if(parent->value.object.size == parent->value.object.alloc) {
        parent->value.object.alloc *= 2;
        parent->value.object.values = realloc(parent->value.object.values, sizeof(JSONObjValue) * parent->value.object.alloc);
        if(!parent->value.object.values) {
            return -1;
        }
    }
    
    parent->value.object.values[parent->value.object.size++] = v;
    
    return 0;
}

static int array_init(JSONParser *p, JSONValue *v) {  
    v->value.array.array = calloc(sizeof(JSONValue*), p->reader_array_alloc);
    if(!v->value.array.array) {
        return -1;
    }
    v->value.array.alloc = p->reader_array_alloc;
    v->value.array.size = 0;
    
    return 0;
}

static int array_add_value(JSONParser *p, JSONValue *parent, JSONValue *v) {
    if(!parent->value.array.array) {
        if(array_init(p, parent)) {
            return -1;
        }
    }
    
    if(parent->value.array.size == parent->value.array.alloc) {
        parent->value.array.alloc *= 2;
        parent->value.array.array = realloc(parent->value.array.array, sizeof(JSONValue*) * parent->value.array.alloc);
        if(!parent->value.array.array) {
            return -1;
        }
    }
    
    parent->value.array.array[parent->value.array.size++] = v;
    
    return 0;
}

static int add_to_parent(JSONParser *p, JSONValue *parent, JSONValue *v) {
    if(!parent) {
        return -1; // shouldn't happen but who knows
    }
    
    int ret = 0;
    if(parent->type == JSON_OBJECT) {
        if(!p->value_name || p->value_name_len == 0) {
            return -1;
        }
        char *valuename = p->value_name;
        p->value_name = NULL;
        
        JSONObjValue newvalue;
        newvalue.name = valuename;
        newvalue.value = v;
        
        ret = obj_add_value(p, parent, newvalue);
    } else if(parent->type == JSON_ARRAY) {
        ret = array_add_value(p, parent, v);
    } else {
        ret = -1; // should also never happen
    }
    
    return ret;
}


static int readvaluestack_add(JSONParser *p, JSONValue *v) {
    if(p->readvalue_nelm == p->readvalue_alloc) {
        p->readvalue_alloc *= 2;
        JSONValue **new_stack = realloc(p->readvalue_stack, sizeof(JSONValue*) * p->readvalue_alloc);
        if(!new_stack) {
            return -1;
        }
        p->readvalue_stack = new_stack;
    }
    p->readvalue_stack[p->readvalue_nelm++] = v;
    return 0;
}

int json_read_value(JSONParser *p, JSONValue **value) {
    *value = NULL;
    if(!p->readvalue_stack) {
        if(setup_read_value(p)) return -1;
    }
    
    while(p->readvalue_nelm > 0 || !p->read_value) {
        //JSONValue *s = p->readvalue_stack[p->readvalue_nelm];
        if(p->value_ready) {
            // value available without another read
            JSONValue *v = init_value(p);
            if(!v) return -1;
            
            if(p->readvalue_nelm > 0) {
                if(add_to_parent(p, p->readvalue_stack[p->readvalue_nelm-1], v)) {
                    return -1;
                }
            } else {
                // set this value as root
                p->read_value = v;
            }
            
            switch(p->reader_type) {
                case JSON_READER_OBJECT_BEGIN: {
                    v->type = JSON_OBJECT;
                    if(readvaluestack_add(p, v)) {
                        return -1;
                    }
                    break;
                }
                case JSON_READER_OBJECT_END: return -1; // should not happen
                case JSON_READER_ARRAY_BEGIN: {
                    v->type = JSON_ARRAY;
                    if(readvaluestack_add(p, v)) {
                        return -1;
                    }
                    break;
                }
                case JSON_READER_ARRAY_END: return -1; // should not happen
                case JSON_READER_STRING: {
                    v->type = JSON_STRING;
                    if(p->value_str) {
                        v->value.string.string = p->value_str;
                        v->value.string.length = p->value_str_len;
                        p->value_str = NULL;
                    }
                    break;
                }
                case JSON_READER_INTEGER: {
                    v->type = JSON_INTEGER;
                    v->value.integer.value = json_reader_int(p);
                    break;
                }
                case JSON_READER_NUMBER: {
                    v->type = JSON_NUMBER;
                    v->value.number.value = json_reader_double(p);
                    break;
                }
                case JSON_READER_LITERAL: {
                    v->type = JSON_LITERAL;
                    v->value.literal.literal = json_reader_literal(p);
                    break;
                }
            }
        } else if(p->readvalue_initialized) {  
            JSONReaderType rt = p->reader_type;
            if(rt == JSON_READER_OBJECT_END || rt == JSON_READER_ARRAY_END) {
                p->readvalue_nelm--;
            }
            // else: p->value_ready is 1, this will be handled in the next run
        }
        
        if(p->readvalue_nelm > 0 || !p->read_value) {
            int r = json_read(p);
            if(r != 1) {
                p->readvalue_initialized = 0;
                return r;
            }
            p->readvalue_initialized = 1;
        }        
    }
    
    *value = p->read_value;    
    p->readvalue_initialized = 0;
    p->read_value = NULL;
    
    return 1;
}

JSONValue* json_obj_get(JSONObject *obj, const char *name) {
    for(size_t i=0;i<obj->size;i++) {
        if(!strcmp(obj->values[i].name, name)) {
            return obj->values[i].value;
        }
    }
    return NULL;
}

JSONValue* json_array_get(JSONArray *array, size_t i) {
    if(i >= array->size) return NULL;
    return array->array[i];
}

void json_value_free(JSONValue *value) {
    switch(value->type) {
        case JSON_OBJECT: {
            JSONObject obj = value->value.object;
            for(size_t i=0;i<obj.size;i++) {
                json_value_free(obj.values[i].value);
                free(obj.values[i].name);
            }
            free(obj.values);
            break;
        }
        case JSON_ARRAY: {
            JSONArray array = value->value.array;
            for(size_t i=0;i<array.size;i++) {
                json_value_free(array.array[i]);
            }
            free(array.array);
            break;
        }
        case JSON_STRING: {
            free(value->value.string.string);
            break;
        }
        default: {
            break;
        }
    }
    free(value);
}

int json_strcmp(JSONValue *jsstr, const char *str) {
    return json_strncmp(jsstr, str, strlen(str));
}

int json_strncmp(JSONValue *jsstr, const char *str, size_t slen) {
    if(jsstr->type != JSON_STRING) {
        return -1;
    }
    size_t jsstrlen = jsstr->value.string.length;
    
    if(jsstrlen != slen) {
        return jsstrlen > slen ? 1 : -1;
    }
    
    return memcmp(jsstr->value.string.string, str, slen);
}