#ifndef DOWNLOADMANAGER_H
#define DOWNLOADMANAGER_H

#include <QObject>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QFileInfo>
#include <QUuid>
#include <QQmlEngine>
#include <QProcess>
#include <QDir>
#include <QStandardPaths>
#include <QUuid>
#include <QtConcurrent/QtConcurrentRun>

#include "common/komplex_global.h"
#include "common/shadertoymetadata.h"
#include "common/shaderpackmetadata.h"
#include "packcompiler.h"

class KOMPLEX_EXPORT DownloadManager : public QObject
{
    Q_OBJECT
    QML_ELEMENT
public:

    enum State
    {
        Idle,
        Downloading,
        Compiling,
        Installing,
        Complete,
        Error
    };
    Q_ENUM(State)

    enum RequestType
    {
        Get,
        Post
    };

    explicit DownloadManager(QObject *parent = nullptr);

    /**
     * @brief downloadImage
     * Downloads the image to tmp from the given url
     * @param url
     */
    auto downloadImage(const QString &author, const QString &authorId, const QString &description, const QUrl &url) noexcept(false) -> void;

    /**
     * @brief downloadPack
     * Attempts to download, compile and install the wallpaper
     * pack from the komplex endpoint.
     * @param id
     * @return File info of the installed pack
     */
    auto downloadPack(const QString &id) noexcept(false) -> void;

    auto compilerOutput() const -> const QString & { return m_compilerOutput; }
    auto errorTitle() const -> const QString & { return m_errorTitle; }
    auto errorMessage() const -> const QString & { return m_errorMessage; }
    auto state() const -> State { return m_state; }
    auto reset() -> void;
    auto downloadProgress() -> qreal { return m_downloadProgress; }
    auto compileProgress() -> qreal;
    auto compileSteps() -> qint64;
    auto compileStepsCompleted() -> qint64;

    auto downloadSize() const -> qint64 { return m_downloadSize; }
    auto setDownloadSize(qint64 downloadSize) -> void;

    auto downloadedBytes() const -> qint64 { return m_downloadedBytes; }
    auto setDownloadedBytes(qint64 downloadedBytes) -> void;

protected:
    auto setError(const QString &title, const QString &message) -> void;
    auto setCompilerOutput(const QString &compilerOutput) -> void;
    auto setState(State state) -> void;
    auto setDownloadProgress(qreal progress) -> void;

signals:
    auto compilerOutputChanged() -> void;
    auto errorChanged() -> void;
    auto stateChanged() -> void;
    auto downloadProgressChanged() -> void;
    auto compileProgressChanged() -> void;
    auto downloadComplete(const QString &uri) -> void;
    auto downloadSizeChanged() -> void;
    auto downloadedBytesChanged() -> void;
    auto compileStepsChanged() -> void;
    auto compileStepsCompletedChanged() -> void;

private:
    auto compile(const QUrl &uri) noexcept(false) -> QUrl;
    auto install(const QUrl &uri) noexcept(false) -> QUrl;
    auto download(const QNetworkRequest &request, const QString &id, RequestType type = Get) -> QFuture<QUrl>;
    auto readShaderToyEntry(const QUrl &uri) noexcept(false) -> ShaderToyEntry;

    QString m_compilerOutput;
    QString m_errorTitle;
    QString m_errorMessage;

    qreal m_downloadProgress = 0;
    qint64 m_downloadSize = 0;
    qint64 m_downloadedBytes = 0;
    qreal m_compileProgress = 0;
    State m_state;

    QMutex m_downloadMutex;

    PackCompiler *m_compiler = nullptr;

    Q_PROPERTY(QString compilerOutput READ compilerOutput WRITE setCompilerOutput NOTIFY compilerOutputChanged FINAL)
    Q_PROPERTY(QString errorTitle READ errorTitle NOTIFY errorChanged FINAL)
    Q_PROPERTY(QString errorMessage READ errorMessage NOTIFY errorChanged FINAL)
    Q_PROPERTY(qreal downloadProgress READ downloadProgress NOTIFY downloadProgressChanged FINAL)
    Q_PROPERTY(qreal compileProgress READ compileProgress NOTIFY compileProgressChanged FINAL)
    Q_PROPERTY(State state READ state NOTIFY stateChanged FINAL)
    Q_PROPERTY(qint64 downloadSize READ downloadSize WRITE setDownloadSize NOTIFY downloadSizeChanged FINAL)
    Q_PROPERTY(qint64 downloadedBytes READ downloadedBytes WRITE setDownloadedBytes NOTIFY downloadedBytesChanged FINAL)
    Q_PROPERTY(qint64 compileSteps READ compileSteps NOTIFY compileStepsChanged FINAL)
    Q_PROPERTY(qint64 compileStepsCompleted READ compileStepsCompleted NOTIFY compileStepsCompletedChanged FINAL)
};
Q_DECLARE_METATYPE(DownloadManager)

#endif // DOWNLOADMANAGER_H