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** Copyright (C) 2018 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt Creator.
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** GNU General Public License Usage
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** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
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#include "clangformatconfigwidget.h"

#include "clangformatconstants.h"
#include "clangformatsettings.h"
#include "clangformatutils.h"
#include "ui_clangformatconfigwidget.h"

#include <clang/Format/Format.h>

#include <coreplugin/icore.h>
#include <projectexplorer/project.h>
#include <projectexplorer/session.h>

#include <QFile>

#include <sstream>

using namespace ProjectExplorer;

namespace ClangFormat {

static void readTable(QTableWidget *table, std::istringstream &stream)
{
    table->horizontalHeader()->hide();
    table->verticalHeader()->hide();

    table->setColumnCount(2);
    table->setRowCount(0);

    std::string line;
    while (std::getline(stream, line)) {
        if (line == "---" || line == "...")
            continue;

        const size_t firstLetter = line.find_first_not_of(' ');
        if (firstLetter == std::string::npos || line.at(firstLetter) == '#')
            continue;

        // Increase indent where it already exists.
        if (firstLetter > 0 && firstLetter < 5)
            line = "    " + line;

        table->insertRow(table->rowCount());
        const size_t colonPos = line.find_first_of(':');
        auto *keyItem = new QTableWidgetItem;
        auto *valueItem = new QTableWidgetItem;

        keyItem->setFlags(keyItem->flags() & ~Qt::ItemFlags(Qt::ItemIsEditable));
        table->setItem(table->rowCount() - 1, 0, keyItem);
        table->setItem(table->rowCount() - 1, 1, valueItem);

        if (colonPos == std::string::npos) {
            keyItem->setText(QString::fromStdString(line));
            valueItem->setFlags(valueItem->flags() & ~Qt::ItemFlags(Qt::ItemIsEditable));
            continue;
        }

        keyItem->setText(QString::fromStdString(line.substr(0, colonPos)));

        const size_t optionValueStart = line.find_first_not_of(' ', colonPos + 1);
        if (optionValueStart == std::string::npos)
            valueItem->setFlags(valueItem->flags() & ~Qt::ItemFlags(Qt::ItemIsEditable));
        else
            valueItem->setText(QString::fromStdString(line.substr(optionValueStart)));
    }

    table->resizeColumnToContents(0);
    table->resizeColumnToContents(1);
}

static QByteArray tableToYAML(QTableWidget *table)
{
    QByteArray text;
    text += "---\n";
    for (int i = 0; i < table->rowCount(); ++i) {
        auto *keyItem = table->item(i, 0);
        auto *valueItem = table->item(i, 1);

        QByteArray itemText = keyItem->text().toUtf8();
        // Change the indent back to 2 spaces
        itemText.replace("      ", "  ");
        if (!valueItem->text().isEmpty() || !itemText.trimmed().startsWith('-'))
            itemText += ": ";
        itemText += valueItem->text().toUtf8() + '\n';

        text += itemText;
    }
    text += "...\n";

    return text;
}

ClangFormatConfigWidget::ClangFormatConfigWidget(ProjectExplorer::Project *project,
                                                 QWidget *parent)
    : CodeStyleEditorWidget(parent)
    , m_project(project)
    , m_ui(std::make_unique<Ui::ClangFormatConfigWidget>())
{
    m_ui->setupUi(this);

    initialize();
}

void ClangFormatConfigWidget::hideGlobalCheckboxes()
{
    m_ui->formatAlways->hide();
    m_ui->formatWhileTyping->hide();
}

void ClangFormatConfigWidget::showGlobalCheckboxes()
{
    m_ui->formatAlways->setChecked(ClangFormatSettings::instance().formatCodeInsteadOfIndent());
    m_ui->formatAlways->show();

    m_ui->formatWhileTyping->setChecked(ClangFormatSettings::instance().formatWhileTyping());
    m_ui->formatWhileTyping->show();
}

void ClangFormatConfigWidget::initialize()
{
    m_ui->projectHasClangFormat->show();
    m_ui->clangFormatOptionsTable->show();
    m_ui->applyButton->show();
    hideGlobalCheckboxes();

    QLayoutItem *lastItem = m_ui->verticalLayout->itemAt(m_ui->verticalLayout->count() - 1);
    if (lastItem->spacerItem())
        m_ui->verticalLayout->removeItem(lastItem);

    if (m_project
        && !m_project->projectDirectory().appendPath(Constants::SETTINGS_FILE_NAME).exists()) {
        m_ui->projectHasClangFormat->setText(tr("No .clang-format file for the project."));
        m_ui->clangFormatOptionsTable->hide();
        m_ui->applyButton->hide();
        m_ui->verticalLayout->addStretch(1);

        connect(m_ui->createFileButton, &QPushButton::clicked,
                this, [this]() {
            createStyleFileIfNeeded(false);
            initialize();
        });
        return;
    }

    m_ui->createFileButton->hide();

    if (m_project) {
        m_ui->projectHasClangFormat->hide();
        connect(m_ui->applyButton, &QPushButton::clicked, this, &ClangFormatConfigWidget::apply);
    } else {
        const Project *currentProject = SessionManager::startupProject();
        if (!currentProject
            || !currentProject->projectDirectory()
                    .appendPath(Constants::SETTINGS_FILE_NAME)
                    .exists()) {
            m_ui->projectHasClangFormat->hide();
        } else {
            m_ui->projectHasClangFormat->setText(
                    tr("Current project has its own .clang-format file "
                       "and can be configured in Projects > Code Style > C++."));
        }
        createStyleFileIfNeeded(true);
        showGlobalCheckboxes();
        m_ui->applyButton->hide();
    }

    fillTable();
}

void ClangFormatConfigWidget::fillTable()
{
    clang::format::FormatStyle style = m_project ? currentProjectStyle() : currentGlobalStyle();

    std::string configText = clang::format::configurationAsText(style);
    std::istringstream stream(configText);
    readTable(m_ui->clangFormatOptionsTable, stream);

}

ClangFormatConfigWidget::~ClangFormatConfigWidget() = default;

void ClangFormatConfigWidget::apply()
{
    if (!m_project) {
        ClangFormatSettings &settings = ClangFormatSettings::instance();
        settings.setFormatCodeInsteadOfIndent(m_ui->formatAlways->isChecked());
        settings.setFormatWhileTyping(m_ui->formatWhileTyping->isChecked());
        settings.write();
    }

    const QByteArray text = tableToYAML(m_ui->clangFormatOptionsTable);
    QString filePath;
    if (m_project)
        filePath = m_project->projectDirectory().appendPath(Constants::SETTINGS_FILE_NAME).toString();
    else
        filePath = Core::ICore::userResourcePath() + "/" + Constants::SETTINGS_FILE_NAME;
    QFile file(filePath);
    if (!file.open(QFile::WriteOnly))
        return;

    file.write(text);
    file.close();
}

} // namespace ClangFormat