/* This file is part of KDevelop
   Copyright (C) 2008 Cédric Pasteur <cedric.pasteur@free.fr>
   Copyright (C) 2011 David Nolden <david.nolden.kdevelop@art-master.de>

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
 */

#include "customscript_plugin.h"

#include <KPluginLoader>
#include <KPluginFactory>
#include <KAboutData>
#include <QTextStream>
#include <QTemporaryFile>
#include <QMimeDatabase>
#include <KProcess>
#include <interfaces/icore.h>
#include <interfaces/isourceformattercontroller.h>
#include <interfaces/isourceformatter.h>
#include <memory>
#include <QDir>
#include <QLoggingCategory>
Q_DECLARE_LOGGING_CATEGORY(CUSTOMSCRIPT)
Q_LOGGING_CATEGORY(CUSTOMSCRIPT, "kdevelop.formatters.customscript")

#include <util/formattinghelpers.h>
#include <interfaces/iprojectcontroller.h>
#include <interfaces/iproject.h>
#include <KMessageBox>
#include <interfaces/iuicontroller.h>
#include <KParts/MainWindow>
#include <KLocalizedString>
#include <interfaces/ilanguagecontroller.h>
#include <language/interfaces/ilanguagesupport.h>
#include <util/path.h>

using namespace KDevelop;

static QPointer<CustomScriptPlugin> indentPluginSingleton;

K_PLUGIN_FACTORY_WITH_JSON(CustomScriptFactory, "kdevcustomscript.json", registerPlugin<CustomScriptPlugin>();)

// Replaces ${KEY} in command with variables[KEY]
static QString replaceVariables( QString command, QMap<QString, QString> variables )
{
	while( command.contains("${"))
	{
		int pos = command.indexOf("${");
		int end = command.indexOf("}", pos+2);
		if(end == -1)
			break;
		QString key = command.mid( pos+2, end-pos-2 );

		if( variables.contains( key ) )
		{
			command.replace( pos, 1 + end - pos, variables[key] );
		}else{
			qCDebug(CUSTOMSCRIPT) << "found no variable while replacing in shell-command" << command << "key" << key << "available:" << variables;
			command.replace( pos, 1 + end - pos, "" );
		}
	}
	return command;
}

CustomScriptPlugin::CustomScriptPlugin(QObject *parent, const QVariantList&)
	: IPlugin("kdevcustomscript", parent)
{
	KDEV_USE_EXTENSION_INTERFACE(ISourceFormatter)
        m_currentStyle = predefinedStyles().at(0);
	indentPluginSingleton = this;
}

CustomScriptPlugin::~CustomScriptPlugin()
{
}

QString CustomScriptPlugin::name()
{
	// This needs to match the X-KDE-PluginInfo-Name entry from the .desktop file!
	return "kdevcustomscript";
}

QString CustomScriptPlugin::caption()
{
	return "Custom Script Formatter";
}

QString CustomScriptPlugin::description()
{
	return i18n("<b>Indent and Format Source Code.</b><br />"
				"This plugin allows using powerful external formatting tools "
				"that can be invoked through the command-line.<br />"
				"For example, the <b>uncrustify</b>, <b>astyle</b> or <b>indent</b> "
				"formatters can be used.<br />"
				"The advantage of command-line formatters is that formatting configurations "
				"can be easily shared by all team members, independent of their preferred IDE.");
}

QString CustomScriptPlugin::formatSourceWithStyle(SourceFormatterStyle style, const QString& text, const QUrl &url, const QMimeType& /*mime*/, const QString& leftContext, const QString& rightContext)
{
	KProcess proc;
	QTextStream ios(&proc);

	std::unique_ptr<QTemporaryFile> tmpFile;

	if (style.content().isEmpty())
	{
		style = predefinedStyle(style.name());
		if (style.content().isEmpty())
		{
			qWarning() << "Empty contents for style" << style.name() << "for indent plugin";
			return text;
		}
	}

	QString useText = text;
	useText = leftContext + useText + rightContext;

	QMap<QString, QString> projectVariables;
	foreach(IProject* project, ICore::self()->projectController()->projects())
		projectVariables[project->name()] = project->path().toUrl().toLocalFile();

	QString command = style.content();

	// Replace ${Project} with the project path
	command = replaceVariables( command, projectVariables );
	command.replace("$FILE", url.toLocalFile());

	if(command.contains("$TMPFILE"))
	{
		tmpFile.reset(new QTemporaryFile(QDir::tempPath() + "/code"));
		tmpFile->setAutoRemove(false);
		if(tmpFile->open())
		{
			qCDebug(CUSTOMSCRIPT) << "using temporary file" << tmpFile->fileName();
			command.replace("$TMPFILE", tmpFile->fileName());
			QByteArray useTextArray = useText.toLocal8Bit();
			if( tmpFile->write(useTextArray) != useTextArray.size() )
			{
				qWarning() << "failed to write text to temporary file";
				return text;
			}

		}else{
			qWarning() << "Failed to create a temporary file";
			return text;
		}
		tmpFile->close();
	}

	qCDebug(CUSTOMSCRIPT) << "using shell command for indentation: " << command;
	proc.setShellCommand(command);
	proc.setOutputChannelMode(KProcess::OnlyStdoutChannel);

	proc.start();
	if(!proc.waitForStarted()) {
		qCDebug(CUSTOMSCRIPT) << "Unable to start indent" << endl;
		return text;
	}

	if(!tmpFile.get())
		proc.write(useText.toLocal8Bit());

	proc.closeWriteChannel();
	if(!proc.waitForFinished()) {
		qCDebug(CUSTOMSCRIPT) << "Process doesn't finish" << endl;
		return text;
	}

	QString output;

	if(tmpFile.get())
	{
		QFile f(tmpFile->fileName());
		if( f.open(QIODevice::ReadOnly) )
		{
			output = QString::fromLocal8Bit(f.readAll());
		}else{
			qWarning() << "Failed opening the temporary file for reading";
			return text;
		}
	}else{
		output = ios.readAll();
	}
	if (output.isEmpty())
	{
		qWarning() << "indent returned empty text for style" << style.name() << style.content();
		return text;
	}

	int tabWidth = 4;
	if((!leftContext.isEmpty() || !rightContext.isEmpty()) && (text.contains('	') || output.contains('	')))
	{
		// If we have to do contex-matching with tabs, determine the correct tab-width so that the context
		// can be matched correctly
		Indentation indent = indentation(url);
		if(indent.indentationTabWidth > 0)
			tabWidth = indent.indentationTabWidth;
	}

    return KDevelop::extractFormattedTextFromContext(output, text, leftContext, rightContext, tabWidth);
}

QString CustomScriptPlugin::formatSource(const QString& text, const QUrl &url, const QMimeType& mime, const QString& leftContext, const QString& rightContext)
{
	return formatSourceWithStyle( KDevelop::ICore::self()->sourceFormatterController()->styleForMimeType( mime ), text, url, mime, leftContext, rightContext );
}

static QList<SourceFormatterStyle> stylesFromLanguagePlugins() {
	QList<KDevelop::SourceFormatterStyle> styles;
	foreach (auto lang, ICore::self()->languageController()->loadedLanguages()) {
		const SourceFormatterItemList& languageStyles = lang->sourceFormatterItems();
		for ( const SourceFormatterStyleItem& item: languageStyles ) {
			if ( item.engine == "customscript" ) {
				styles << item.style;
			}
		}
	}
	return styles;
};

KDevelop::SourceFormatterStyle CustomScriptPlugin::predefinedStyle(const QString& name)
{
	for ( auto langStyle: stylesFromLanguagePlugins() ) {
		qCDebug(CUSTOMSCRIPT) << "looking at style from language with custom sample" << langStyle.description() << langStyle.overrideSample();
		if ( langStyle.name() == name ) {
			return langStyle;
		}
	}
	SourceFormatterStyle result(name);
	if (name == "GNU_indent_GNU")
	{
		result.setCaption(i18n("Gnu Indent: GNU"));
		result.setContent("indent");
	} else if (name == "GNU_indent_KR") {
		result.setCaption(i18n("Gnu Indent: Kernighan & Ritchie"));
		result.setContent("indent -kr");
	} else if (name == "GNU_indent_orig") {
		result.setCaption(i18n("Gnu Indent: Original Berkeley indent style"));
		result.setContent("indent -orig");
	} else if(name == "kdev_format_source") {
		result.setCaption("KDevelop: kdev_format_source");
		result.setContent("kdev_format_source $FILE $TMPFILE");
		result.setUsePreview(false);
		result.setDescription(i18n( "Description:<br />"
									"<b>kdev_format_source</b> is a script bundled with KDevelop "
			                        "which allows using fine-grained formatting rules by placing "
									"meta-files called <b>format_sources</b> into the file-system.<br /><br />"
									"Each line of the <b>format_sources</b> files defines a list of wildcards "
									"followed by a colon and the used formatting-command.<br /><br />"
									"The formatting-command should use <b>$TMPFILE</b> to reference the "
									"temporary file to reformat.<br /><br />"
									"Example:<br />"
									"<b>*.cpp *.h : myformatter $TMPFILE</b><br />"
									"This will reformat all files ending with <b>.cpp</b> or <b>.h</b> using "
									"the custom formatting script <b>myformatter</b>.<br /><br />"
									"Example: <br />"
									"<b>subdir/* : uncrustify -l CPP -f $TMPFILE -c uncrustify.config -o $TMPFILE</b> <br />"
									"This will reformat all files in subdirectory <b>subdir</b> using the <b>uncrustify</b> "
									"tool with the config-file <b>uncrustify.config</b>." ));
	}
	result.setMimeTypes({
		{"text/x-c++src", "C++"}, {"text/x-chdr", "C"},
		{"text/x-c++hdr", "C++"}, {"text/x-csrc", "C"},
		{"text/x-java", "Java"}, {"text/x-csharp", "C#"}
	});
	return result;
}

QList<KDevelop::SourceFormatterStyle> CustomScriptPlugin::predefinedStyles()
{
	QList<KDevelop::SourceFormatterStyle> styles = stylesFromLanguagePlugins();
	styles << predefinedStyle("kdev_format_source");
	styles << predefinedStyle("GNU_indent_GNU");
	styles << predefinedStyle("GNU_indent_KR");
	styles << predefinedStyle("GNU_indent_orig");
	return styles;
}

KDevelop::SettingsWidget* CustomScriptPlugin::editStyleWidget(const QMimeType& mime)
{
	Q_UNUSED(mime);
	return new CustomScriptPreferences();
}

static QString formattingSample()
{
    return
    "// Formatting\n"
	"void func(){\n"
    "\tif(isFoo(a,b))\n"
    "\tbar(a,b);\n"
    "if(isFoo)\n"
    "\ta=bar((b-c)*a,*d--);\n"
    "if(  isFoo( a,b ) )\n"
    "\tbar(a, b);\n"
    "if (isFoo) {isFoo=false;cat << isFoo <<endl;}\n"
    "if(isFoo)DoBar();if (isFoo){\n"
    "\tbar();\n"
    "}\n"
    "\telse if(isBar()){\n"
    "\tannotherBar();\n"
    "}\n"
    "int var = 1;\n"
    "int *ptr = &var;\n"
    "int &ref = i;\n"
    "\n"
    "QList<int>::const_iterator it = list.begin();\n"
    "}\n"
    "namespace A {\n"
    "namespace B {\n"
    "void foo() {\n"
    "  if (true) {\n"
    "    func();\n"
    "  } else {\n"
    "    // bla\n"
    "  }\n"
    "}\n"
    "}\n"
    "}\n";
}

static QString indentingSample()
{
    return
    "// Indentation\n"
    "#define foobar(A)\\\n"
    "{Foo();Bar();}\n"
    "#define anotherFoo(B)\\\n"
    "return Bar()\n"
    "\n"
    "namespace Bar\n"
    "{\n"
    "class Foo\n"
    "{public:\n"
    "Foo();\n"
    "virtual ~Foo();\n"
    "};\n"
    "switch (foo)\n"
    "{\n"
    "case 1:\n"
    "a+=1;\n"
    "break;\n"
    "case 2:\n"
    "{\n"
    "a += 2;\n"
    " break;\n"
    "}\n"
    "}\n"
    "if (isFoo)\n"
    "{\n"
    "bar();\n"
    "}\n"
    "else\n"
    "{\n"
    "anotherBar();\n"
    "}\n"
    "int foo()\n"
    "\twhile(isFoo)\n"
    "\t\t{\n"
    "\t\t\t...\n"
    "\t\t\tgoto error;\n"
    "\t\t....\n"
    "\t\terror:\n"
    "\t\t\t...\n"
    "\t\t}\n"
    "\t}\n"
    "fooArray[]={ red,\n"
    "\tgreen,\n"
    "\tdarkblue};\n"
    "fooFunction(barArg1,\n"
    "\tbarArg2,\n"
    "\tbarArg3);\n";
}

QString CustomScriptPlugin::previewText(const SourceFormatterStyle& style, const QMimeType& /*mime*/)
{
	if ( ! style.overrideSample().isEmpty() ) {
		return style.overrideSample();
	}
	return formattingSample() + "\n\n" + indentingSample();
}


QStringList CustomScriptPlugin::computeIndentationFromSample( const QUrl &url )
{
	QStringList ret;

    auto languages = ICore::self()->languageController()->languagesForUrl( url );
    if (languages.isEmpty())
        return ret;

    QString sample = languages[0]->indentationSample();
    QString formattedSample = formatSource(sample, url, QMimeDatabase().mimeTypeForUrl(url), QString(), QString());

    QStringList lines = formattedSample.split( "\n" );
    foreach( QString line, lines )
	{
	  if( !line.isEmpty() && line[0].isSpace() )
	  {
		QString indent;
		foreach( QChar c, line )
		{
		  if( c.isSpace() )
			indent.push_back( c );
		  else
			break;
		}
		if(!indent.isEmpty() && !ret.contains(indent))
			ret.push_back(indent);
	  }
	}

	return ret;
}

CustomScriptPlugin::Indentation CustomScriptPlugin::indentation( const QUrl &url )
{
    Indentation ret;
    QStringList indent = computeIndentationFromSample( url );
    if( indent.isEmpty() )
    {
        qCDebug(CUSTOMSCRIPT) << "failed extracting a valid indentation from sample for url" << url;
        return ret; // No valid indentation could be extracted
    }

	if( indent[0].contains( ' ' ) )
		ret.indentWidth = indent[0].count(' ');

	if( !indent.join("").contains('	') )
		ret.indentationTabWidth = -1; // Tabs are not used for indentation

	if( indent[0] == "	" )
	{
		// The script indents with tabs-only
		// The problem is that we don't know how
		// wide a tab is supposed to be.
		//
		// We need indentation-width=tab-width
		// to make the editor do tab-only formatting,
		// so choose a random with of 4.
		ret.indentWidth = 4;
		ret.indentationTabWidth = 4;
	}else if(ret.indentWidth) {
		// Tabs are used for indentation, alongside with spaces
		// Try finding out how many spaces one tab stands for.
		// Do it by assuming a uniform indentation-step with each level.

		for(int pos = 0; pos < indent.size(); ++pos)
		{
			if(indent[pos] == "	" && pos >= 1)
			{
				// This line consists of only a tab.
				int prevWidth = indent[pos-1].length();
				int prevPrevWidth = (pos >= 2) ? indent[pos-2].length() : 0;
				int step = prevWidth - prevPrevWidth;
				qCDebug(CUSTOMSCRIPT) << "found in line " << pos << prevWidth << prevPrevWidth << step;
				if(step > 0 && step <= prevWidth)
				{
					qCDebug(CUSTOMSCRIPT) << "Done";
					ret.indentationTabWidth = prevWidth + step;
					break;
				}
			}
		}
	}

    qCDebug(CUSTOMSCRIPT) << "indent-sample" << "\"" + indent.join("\n") + "\"" << "extracted tab-width" << ret.indentationTabWidth << "extracted indentation width" << ret.indentWidth;

    return ret;
}

void CustomScriptPreferences::updateTimeout()
{
	const QString& text = indentPluginSingleton.data()->previewText(m_style, QMimeType());
    QString formatted = indentPluginSingleton.data()->formatSourceWithStyle(m_style, text, QUrl(), QMimeType());
    emit previewTextChanged ( formatted );
}

CustomScriptPreferences::CustomScriptPreferences()
{
    m_updateTimer = new QTimer ( this );
    m_updateTimer->setSingleShot ( true );
    connect ( m_updateTimer, &QTimer::timeout, this, &CustomScriptPreferences::updateTimeout );
    m_vLayout = new QVBoxLayout ( this );
    m_captionLabel = new QLabel;
    m_vLayout->addWidget ( m_captionLabel );
    m_vLayout->addSpacing ( 10 );
    m_hLayout = new QHBoxLayout;
    m_vLayout->addLayout ( m_hLayout );
    m_commandLabel = new QLabel;
    m_hLayout->addWidget ( m_commandLabel );
    m_commandEdit = new QLineEdit;
    m_hLayout->addWidget ( m_commandEdit );
    m_commandLabel->setText ( i18n("Command: ") );
    m_vLayout->addSpacing ( 10 );
    m_bottomLabel = new QLabel;
    m_vLayout->addWidget ( m_bottomLabel );
    m_bottomLabel->setTextFormat ( Qt::RichText );
    m_bottomLabel->setText (
        i18n ( "<i>You can enter an arbitrary shell command.</i><br />"
               "The unformatted source-code is reached to the command <br />"
			   "through the standard input, and the <br />"
               "formatted result is read from the standard output.<br />"
			   "<br />"
               "If you add <b>$TMPFILE</b> into the command, then <br />"
               "a temporary file is used for transferring the code." ) );
    connect ( m_commandEdit, &QLineEdit::textEdited, this, &CustomScriptPreferences::textEdited );

	m_vLayout->addSpacing ( 10 );

	m_moreVariablesButton = new QPushButton( i18n("More Variables") );
	connect( m_moreVariablesButton, &QPushButton::clicked, this, &CustomScriptPreferences::moreVariablesClicked );
	m_vLayout->addWidget( m_moreVariablesButton );

}

void CustomScriptPreferences::load ( const KDevelop::SourceFormatterStyle& style )
{
    m_style = style;
    m_commandEdit->setText ( style.content() );
    m_captionLabel->setText ( i18n ( "Style: %1", style.caption() ) );

    updateTimeout();
}

QString CustomScriptPreferences::save()
{
    return m_commandEdit->text();
}

void CustomScriptPreferences::moreVariablesClicked ( bool )
{
	KMessageBox::information( ICore::self()->uiController()->activeMainWindow(),
	i18n("<b>$TMPFILE</b> will be replaced with the path to a temporary file. <br />"
		 "The code will be written into the file, the temporary <br />"
         "file will be substituted into that position, and the result <br />"
         "will be read out of that file. <br />"
		 "<br />"
		 "<b>$FILE</b> will be replaced with the path of the original file. <br />"
		 "The contents of the file must not be modified, changes are allowed <br />"
         "only in $TMPFILE.<br />"
		 "<br />"
		 "<b>${PROJECT_NAME}</b> will be replaced by the path of <br />"
		 "the currently open project with the matching name."

	), i18n("Variable Replacements") );
}

#include "customscript_plugin.moc"

// kate: indent-mode cstyle; space-indent off; tab-width 4;
