// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0

#pragma once

#include <QTextCursor>

#include <QTextDocument>

#include "../assistenums.h"

namespace TextEditor {

class AssistInterface
{
public:
    AssistInterface(const QByteArray &text,
                    int position)
        : textDocument_(QString::fromUtf8(text)),
          position_(position)
    {}

    AssistInterface(QTextDocument *textDocument,
                    int position,
                    const QString &fileName,
                    AssistReason reason)
        : textDocument_(textDocument),
          fileName_(fileName),
          position_(position),
          reason_(reason)
    {}

    QTextDocument *textDocument() const;
    virtual int position() const;
    virtual QChar characterAt(int position) const;
    virtual QString textAt(int position, int length) const;
    virtual QString fileName() const;
    virtual AssistReason reason() const;


private:
    mutable QTextDocument textDocument_;
    QString fileName_;
    int position_;
    AssistReason reason_ = IdleEditor;
};

inline QTextDocument *AssistInterface::textDocument() const
{
    return &textDocument_;
}

inline int AssistInterface::position() const
{
    return position_;
}

inline QChar AssistInterface::characterAt(int position) const
{
    return textDocument_.characterAt(position);
}

inline QString AssistInterface::textAt(int position, int length) const
{
    QTextCursor textCursor(&textDocument_);
    if (position < 0)
        position = 0;
    textCursor.movePosition(QTextCursor::End);
    if (position + length > textCursor.position())
        length = textCursor.position() - position;

    textCursor.setPosition(position);
    textCursor.setPosition(position + length, QTextCursor::KeepAnchor);

    // selectedText() returns U+2029 (PARAGRAPH SEPARATOR) instead of newline
    return textCursor.selectedText().replace(QChar::ParagraphSeparator, QLatin1Char('\n'));
}

inline AssistReason AssistInterface::reason() const
{
    return reason_;
}

inline QString AssistInterface::fileName() const
{
    return fileName_;
}
}