// Copyright (C) 2023 The Qt Company Ltd.
// Copyright (C) 2019 Alexey Edelev <semlanik@gmail.com>
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include "simplechatengine.h"

#include <QGrpcHttp2Channel>
#include <QGrpcChannelOptions>

#include <qprotobufregistration.h>

#include <QDebug>
#include <QFile>
#include <QCryptographicHash>
#include <QDateTime>
#include <QClipboard>
#include <QGuiApplication>
#include <QMimeData>
#include <QImage>
#include <QByteArray>
#include <QBuffer>

#include <memory>

SimpleChatEngine::SimpleChatEngine(QObject *parent)
    : QObject(parent),
      m_state(Disconnected),
      m_client(new qtgrpc::examples::chat::SimpleChat::Client),
      m_clipBoard(QGuiApplication::clipboard())
{
    if (m_clipBoard) {
        QObject::connect(m_clipBoard, &QClipboard::dataChanged, this,
                         &SimpleChatEngine::clipBoardContentTypeChanged);
    }
}

SimpleChatEngine::~SimpleChatEngine()
{
    delete m_client;
}

void SimpleChatEngine::login(const QString &name, const QString &password)
{
    if (m_state != Disconnected)
        return;

    setState(Connecting);
    QUrl url("http://localhost:65002");

    // ![0]
    QGrpcChannelOptions channelOptions;
    QHash<QByteArray, QByteArray> metadata = {
        { "user-name", { name.toUtf8() } },
        { "user-password", { password.toUtf8() } },
    };
    channelOptions.setMetadata(metadata);
    std::shared_ptr<QAbstractGrpcChannel>
        channel = std::make_shared<QGrpcHttp2Channel>(url, channelOptions);
    // ![0]

    m_client->attachChannel(channel);

    // ![1]
    auto stream = m_client->messageList(qtgrpc::examples::chat::None());
    auto streamPtr = stream.get();
    QObject::connect(
        streamPtr, &QGrpcServerStream::finished, this,
        [this, stream = std::move(stream)](const QGrpcStatus &status) {
            if (!status.isOk()) {
                qCritical() << "Stream error(" << status.code() << "):" << status.message();
            }
            if (status.code() == QtGrpc::StatusCode::Unauthenticated) {
                emit authFailed();
            } else if (status.code() != QtGrpc::StatusCode::Ok) {
                emit networkError(status.message());
                setState(Disconnected);
            } else {
                setState(Disconnected);
            }
        },
        Qt::SingleShotConnection);

    QObject::connect(streamPtr, &QGrpcServerStream::messageReceived, this,
                     [this, name, password, stream = streamPtr]() {
                         if (m_userName != name) {
                             m_userName = name;
                             m_password = password;
                             emit userNameChanged();
                         }
                         setState(Connected);
                         if (const auto msg = stream->read<qtgrpc::examples::chat::ChatMessages>())
                             m_messages.append(msg->messages());
                     });
    // ![1]
}

void SimpleChatEngine::sendMessage(const QString &content)
{
    // ![2]
    qtgrpc::examples::chat::ChatMessage msg;
    msg.setContent(content.toUtf8());
    msg.setType(qtgrpc::examples::chat::ChatMessage::ContentType::Text);
    msg.setTimestamp(QDateTime::currentMSecsSinceEpoch());
    msg.setFrom(m_userName);

    std::unique_ptr<QGrpcCallReply> reply = m_client->sendMessage(msg);
    // We explicitly take a copy of the reply pointer, since moving it into
    // the lambda would make the get() function invalid.
    // Reply's lifetime will be extended until finished() is emitted.
    // Qt::SingleShotConnection is needed to destroy the lambda (and its capture).
    auto *replyPtr = reply.get();
    connect(
        replyPtr, &QGrpcCallReply::finished, this,
        [reply = std::move(reply)](const QGrpcStatus &status) {
            if (!status.isOk())
                qDebug() << "Failed to send message: " << status;
        },
        Qt::SingleShotConnection);
    // ![2]
}

SimpleChatEngine::ContentType SimpleChatEngine::clipBoardContentType() const
{
    if (m_clipBoard != nullptr) {
        const QMimeData *mime = m_clipBoard->mimeData();
        if (mime != nullptr) {
            if (mime->hasImage() || mime->hasUrls())
                return SimpleChatEngine::ContentType::Image;
            else if (mime->hasText())
                return SimpleChatEngine::ContentType::Text;
        }
    }
    return SimpleChatEngine::ContentType::Unknown;
}

void SimpleChatEngine::sendImageFromClipboard()
{
    if (m_clipBoard == nullptr)
        return;

    QByteArray imgData;
    const QMimeData *mime = m_clipBoard->mimeData();
    if (mime != nullptr) {
        if (mime->hasImage()) {
            QImage img = mime->imageData().value<QImage>();
            img = img.scaled(300, 300, Qt::KeepAspectRatio);
            QBuffer buffer(&imgData);
            buffer.open(QIODevice::WriteOnly);
            img.save(&buffer, "PNG");
            buffer.close();
        } else if (mime->hasUrls()) {
            QUrl imgUrl = mime->urls().at(0);
            if (!imgUrl.isLocalFile()) {
                qWarning() << "Only supports transfer of local images";
                return;
            }
            QImage img(imgUrl.toLocalFile());
            if (img.isNull()) {
                qWarning() << "Invalid image format";
                return;
            }

            QBuffer buffer(&imgData);
            buffer.open(QIODevice::WriteOnly);
            img.save(&buffer, "PNG");
            buffer.close();
        }
    }

    if (imgData.isEmpty())
        return;

    qtgrpc::examples::chat::ChatMessage msg;
    msg.setContent(imgData);
    msg.setType(qtgrpc::examples::chat::ChatMessage::ContentType::Image);
    msg.setTimestamp(QDateTime::currentMSecsSinceEpoch());
    msg.setFrom(m_userName);

    std::unique_ptr<QGrpcCallReply> reply = m_client->sendMessage(msg);
    auto *replyPtr = reply.get();
    connect(
        replyPtr, &QGrpcCallReply::finished, this,
        [reply = std::move(reply)](const QGrpcStatus &status) {
            if (!status.isOk())
                qDebug() << "Failed to send clipboard message: " << status;
        },
        Qt::SingleShotConnection);
}

ChatMessageModel *SimpleChatEngine::messages()
{
    return &m_messages;
}

QString SimpleChatEngine::userName() const
{
    return m_userName;
}

SimpleChatEngine::State SimpleChatEngine::state() const
{
    return m_state;
}

void SimpleChatEngine::setState(SimpleChatEngine::State state)
{
    if (m_state != state) {
        m_state = state;
        emit stateChanged();
    }
}