/* SPDX-License-Identifier: GPL-3.0-or-later */
/* Copyright 2022 Ivan Polyakov */

#include "query.h"
#include "utils.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int rpd_query_parse(rpd_keyval *dest, const char *src)
{
    int len = count_char_entries(src, '=');
    if (!len) {
        dest->items = NULL;
        dest->capacity = 0;
        dest->size = 0;
        return 0;
    }

    char *query = strdup(src);
    if (!query)
        return 1;

    dest->items = realloc(dest->items, sizeof(rpd_keyval_item *) * len);
    if (!dest->items)
        return 2;
    dest->capacity = len;

    char *tokens = query, *p = query;
    int i = 0;
    while ((p = strsep(&tokens, "&\n")) && i < len) {
        char *param, *val;

        if (*p == '=')
            continue;
        param = strtok(p, "=");
        val = strtok(NULL, "=");

        if (param) {
            dest->items[i].key = strdup(param);
            dest->items[i].val = val ? strdup(val) : NULL;
            i++;
        }
    }

    dest->size = i;
    dest->capacity = i;
    free(query);
    return 0;
}

char *rpd_query_str(const rpd_keyval *query)
{
    size_t len = 0;
    rpd_keyval_item *item;
    for (int i = 0; i < query->size; i++) {
        item = &query->items[i];
        if (!item->key || !item->val)
            continue;
        len += strlen(item->key) + strlen(item->val);
    }

    /* len + number of key-val delimeters + terminating char */
    size_t size = len + (query->size - 1) + 1;
    if (size <= 0)
        return NULL;

    char *buff = (char *) malloc(sizeof(char) * size);
    if (!buff)
        return NULL;
    buff[size - 1] = '\0';

    size_t offset = 0;
    for (int i = 0; i < query->size; i++) {
        item = &query->items[i];
        if (!item->key || !item->val)
            continue;
        offset += sprintf(buff + offset, "%s=%s", item->key, item->val);

        if (i + 1 < query->size) {
            buff[offset] = '&';
            offset++;
        }
    }

    if (buff[offset - 1] == '&') {
        buff[offset - 1] = '\0';
    }

    return buff;
}