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

#define MAXLN 1024

struct node{
   char content[MAXLN];
   struct node * next;
};

int parsejson(FILE *, FILE *);
struct node * parseline(FILE *, char line[MAXLN], int *, int *, int *, struct node *,
              struct node *);
int skipwhsp(char line[MAXLN], int *);
void freelist(struct node *);

int main(void)
{
    FILE * f = fopen("convertor.in", "r");
    FILE * g = fopen("convertor.out", "w");

    parsejson(f, g);

    fclose(f);
    fclose(g);

    return 0;
}

int parsejson(FILE * f, FILE * g) {
    struct node * first_val = (struct node *)malloc(sizeof(first_val));
    struct node * last_val = first_val;

    char line[MAXLN];
    int isatt = 1, isfirstobj = 1, isfirstval = 1;

    while(!feof(f)) {
        fgets(line, MAXLN, f);
        last_val = parseline(g, line, &isfirstobj, &isfirstval, &isatt, first_val,
            last_val);
        if(last_val == 0) {
            break;
        }
    }

    freelist(first_val);

    return 0;
}

struct node * parseline(FILE * g, char line[MAXLN], int * isfirstobj, int * isfirstval,
              int * isatt, struct node * first_val, struct node * last_val) {
    struct node * curr;
    char buffer[MAXLN];
    int buflen = 0, crt = 0;

    skipwhsp(line, &crt);

    if(*isfirstobj) {
        if(line[crt] == '[') {
            crt++;
            skipwhsp(line, &crt); //citesc pana la {
        }
    }

    while(crt < strlen(line)) {
        //tratam cazul "
        if(line[crt] == '"') {
            buflen = 0;
            crt++;
            while(line[crt] != '"') {
                buffer[buflen++] = line[crt++];
            }
            buffer[buflen++] = '\0';
            crt++;

            if(*isatt) {
                if(*isfirstobj) {
                    fprintf(g, "%s,", buffer);
                }
            } else {
                if(!(*isfirstval)) {
                    if(*isfirstobj) {
                        last_val->next = (struct node *)malloc(sizeof(struct node));
                    }
                    last_val = last_val->next;
                } else {
                    *isfirstval = 0;
                }
                strcpy(last_val->content, buffer);
            }

            *isatt = 1 - *isatt; // printf("%s\n", buffer);
        } else if(line[crt] >= '0' && line[crt] <= '9') {
            //tratam cazul 0-9; sigur e valoare
            buflen = 0;
            while('0' <= line[crt] && '9' >= line[crt]) {
                buffer[buflen++] = line[crt++];
            }
            buffer[buflen++] = '\0';
            crt++;

            //pune in lista
            if(!(*isfirstval)) {
                if(*isfirstobj) {
                    last_val->next = (struct node *)malloc(sizeof(struct node));
                }
                last_val = last_val->next;
            } else {
                *isfirstval = 0;
            }
            strcpy(last_val->content, buffer);

            *isatt = 1;
        } else if(strchr(",:{", line[crt]) != NULL) {
            //peste {, : si , trecem
            crt++;
        } else if(line[crt] == '}') {
            //tratam cazul }
            fprintf(g, "\n");
            curr = first_val;
            while(curr != NULL) {
                fprintf(g, "%s,", curr->content);
                if(curr != NULL) {
                    curr = curr->next;
                }
            }

            *isfirstobj = 0;
            *isfirstval = 1;
            last_val = first_val;

            crt++;
        } else if(line[crt] == ']') {
            return 0;
        }

        skipwhsp(line, &crt);
    }

    return last_val;
}

int skipwhsp(char line[MAXLN], int * crt) {
    while(strchr(" \t\n", line[*crt]) != NULL) {
        (*crt)++;
    }
    return *crt;
}

void freelist(struct node * first) {
    struct node * ante = first;
    struct node * curr = ante->next;

    while(ante != NULL) {
        free(ante);
        ante = curr;
        if(curr != NULL) {
            curr = curr->next;
        }
    }
}