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

#include <json-c/json.h>

#include "../include/jsonFile.h"

int existsFile(const char *fname) {
    FILE *file = fopen(fname, "r");
    if (file) {
        fclose(file);
        return 1;
    }
    return 0;
}

int createFile(const char *fname) {
    json_object *arr = json_object_new_array();
    if (!arr)
        return -1;

    int res = json_object_to_file_ext(fname, arr, JSON_C_TO_STRING_PRETTY);
    json_object_put(arr);
    return (res == 0) ? 0 : -1;
}

int renameDataFile(const char *oldName, const char *newName) {
    return (rename(oldName, newName) == 0) ? 0 : -1;
}

static json_object *loadRawArray(const char *fname) {
    if (!existsFile(fname) && createFile(fname) != 0)
        return NULL;

    FILE *f = fopen(fname, "r");
    if (!f)
        return NULL;

    int empty = (fgetc(f) == EOF);
    fclose(f);
    if (empty)
        return json_object_new_array();

    json_object *arr = json_object_from_file(fname);
    if (!arr)
        return NULL;

    if (!json_object_is_type(arr, json_type_array)) {
        json_object_put(arr);
        return NULL;
    }

    return arr;
}

json_object *loadJsonArray(const char *fname) {
    return loadRawArray(fname);
}

int saveJsonArray(const char *fname, json_object *arr) {
    if (!arr)
        return -1;
    return (json_object_to_file_ext(fname, arr, JSON_C_TO_STRING_PRETTY) == 0) ? 0 : -1;
}

json_object *findItemByName(json_object *arr, const char *name) {
    if (!arr || !name)
        return NULL;

    size_t n = json_object_array_length(arr);
    for (size_t i = 0; i < n; i++) {
        json_object *item = json_object_array_get_idx(arr, i);
        json_object *jname = NULL;

        if (json_object_object_get_ex(item, "name", &jname) &&
            strcmp(json_object_get_string(jname), name) == 0)
            return item;
    }

    return NULL;
}

int removeItemByName(json_object *arr, const char *name) {
    if (!arr || !name)
        return -1;

    size_t n = json_object_array_length(arr);
    for (size_t i = 0; i < n; i++) {
        json_object *item = json_object_array_get_idx(arr, i);
        json_object *jname = NULL;

        if (json_object_object_get_ex(item, "name", &jname) &&
            strcmp(json_object_get_string(jname), name) == 0) {
            json_object_array_del_idx(arr, (int)i, 1);
            return 0;
        }
    }

    return 1;
}

int renameItemByName(json_object *arr, const char *oldName, const char *newName) {
    if (!arr || !oldName || !newName)
        return -1;

    json_object *item = findItemByName(arr, oldName);
    if (!item)
        return 1;

    json_object_object_add(item, "name", json_object_new_string(newName));
    return 0;
}