/*
 * Copyright (c) 2021, [Ribose Inc](https://www.ribose.com).
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "json-utils.h"
#include "logging.h"
#include "crypto/mem.h"

namespace rnp {
namespace json {

/* Internal helper: pull a pointer to a field if it exists and matches the
 * type predicate, otherwise nullptr. */
static nlohmann::ordered_json *
get_field(nlohmann::ordered_json &obj,
          const char *            name,
          bool (*pred)(const nlohmann::ordered_json &))
{
    if (!obj.is_object() || !obj.contains(name)) {
        return nullptr;
    }
    nlohmann::ordered_json *field = &obj[name];
    if (!pred(*field)) {
        return nullptr;
    }
    return field;
}

bool
add(nlohmann::ordered_json &obj, const char *name, const char *value)
{
    obj[name] = value;
    return true;
}

bool
add(nlohmann::ordered_json &obj, const char *name, const char *value, size_t len)
{
    obj[name] = std::string(value, len);
    return true;
}

bool
add(nlohmann::ordered_json &obj, const char *name, const std::string &value)
{
    obj[name] = value;
    return true;
}

bool
add(nlohmann::ordered_json &obj, const char *name, bool value)
{
    obj[name] = value;
    return true;
}

bool
add(nlohmann::ordered_json &obj, const char *name, int value)
{
    obj[name] = value;
    return true;
}

bool
add(nlohmann::ordered_json &obj, const char *name, uint64_t value)
{
    obj[name] = value;
    return true;
}

bool
add_hex(nlohmann::ordered_json &obj, const char *name, const uint8_t *val, size_t val_len)
{
    if (val_len > 1024 * 1024) {
        RNP_LOG("too large json hex field: %zu", val_len);
        val_len = 1024 * 1024;
    }
    obj[name] = bin_to_hex(val, val_len, rnp::HexFormat::Lowercase);
    return true;
}

bool
add_hex(nlohmann::ordered_json &obj, const char *name, const std::vector<uint8_t> &vec)
{
    return add_hex(obj, name, vec.data(), vec.size());
}

bool
add(nlohmann::ordered_json &obj, const char *name, const pgp::KeyID &keyid)
{
    return add_hex(obj, name, keyid.data(), keyid.size());
}

bool
add(nlohmann::ordered_json &obj, const char *name, const pgp::Fingerprint &fp)
{
    return add_hex(obj, name, fp.data(), fp.size());
}

bool
array_add(nlohmann::ordered_json &arr, const char *val)
{
    arr.push_back(val);
    return true;
}

bool
array_add(nlohmann::ordered_json &arr, nlohmann::ordered_json val)
{
    arr.push_back(std::move(val));
    return true;
}

bool
get_str(nlohmann::ordered_json &obj, const char *name, std::string &out, bool del)
{
    auto *field =
      get_field(obj, name, [](const nlohmann::ordered_json &v) { return v.is_string(); });
    if (!field) {
        return false;
    }
    out = field->get_ref<const std::string &>();
    if (del) {
        obj.erase(name);
    }
    return true;
}

bool
get_int(nlohmann::ordered_json &obj, const char *name, int &out, bool del)
{
    auto *field = get_field(
      obj, name, [](const nlohmann::ordered_json &v) { return v.is_number_integer(); });
    if (!field) {
        return false;
    }
    out = field->get<int>();
    if (del) {
        obj.erase(name);
    }
    return true;
}

bool
get_uint64(nlohmann::ordered_json &obj, const char *name, uint64_t &out, bool del)
{
    auto *field =
      get_field(obj, name, [](const nlohmann::ordered_json &v) { return v.is_number(); });
    if (!field) {
        return false;
    }
    out = field->get<uint64_t>();
    if (del) {
        obj.erase(name);
    }
    return true;
}

bool
get_str_arr(nlohmann::ordered_json &  obj,
            const char *              name,
            std::vector<std::string> &out,
            bool                      del)
{
    auto *arr =
      get_field(obj, name, [](const nlohmann::ordered_json &v) { return v.is_array(); });
    if (!arr) {
        return false;
    }
    out.clear();
    for (const auto &item : *arr) {
        if (!item.is_string()) {
            return false;
        }
        out.push_back(item.get_ref<const std::string &>());
    }
    if (del) {
        obj.erase(name);
    }
    return true;
}

nlohmann::ordered_json *
get_obj(nlohmann::ordered_json &obj, const char *name)
{
    return get_field(obj, name, [](const nlohmann::ordered_json &v) { return v.is_object(); });
}

std::string
dump_pretty(const nlohmann::ordered_json &jso)
{
    /* nlohmann::ordered_json::dump(2) produces 2-space indent but with `": ` after
     * keys. json-c uses `":` (no space). Walk the dumped string and remove
     * the space after structural colons (colons that follow an unescaped
     * closing quote of a key). Inside-string `":` is part of a value and
     * is left untouched because the preceding quote is escaped (`\"`). */
    std::string raw = jso.dump(2);
    std::string out;
    out.reserve(raw.size());
    bool   in_string = false;
    bool   escaped = false;
    size_t i = 0;
    while (i < raw.size()) {
        char c = raw[i];
        if (escaped) {
            out.push_back(c);
            escaped = false;
            i++;
            continue;
        }
        if (in_string) {
            if (c == '\\') {
                escaped = true;
                out.push_back(c);
                i++;
                continue;
            }
            if (c == '"') {
                in_string = false;
            }
            out.push_back(c);
            i++;
            continue;
        }
        if (c == '"') {
            in_string = true;
            out.push_back(c);
            i++;
            continue;
        }
        /* structural colon followed by space → drop the space */
        if (c == ':' && i + 1 < raw.size() && raw[i + 1] == ' ') {
            out.push_back(':');
            i += 2; /* skip the colon and its trailing space */
            continue;
        }
        out.push_back(c);
        i++;
    }
    return out;
}

} // namespace json
} // namespace rnp