/*
   Copyright 2007 David Nolden <david.nolden.kdevelop@art-master.de>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License version 2 as published by the Free Software Foundation.

   This library 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
   Library General Public License for more details.

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

#include "abstractnavigationcontext.h"

#include <KLocalizedString>

#include <qtcompat_p.h>

#include "abstractdeclarationnavigationcontext.h"
#include "abstractnavigationwidget.h"
#include "usesnavigationcontext.h"
#include "../../../interfaces/icore.h"
#include "../../../interfaces/idocumentcontroller.h"
#include "../functiondeclaration.h"
#include "../namespacealiasdeclaration.h"
#include "../types/functiontype.h"
#include "../types/structuretype.h"
#include <debug.h>
#include <interfaces/icontextbrowser.h>
#include <interfaces/idocumentationcontroller.h>
#include <interfaces/iplugincontroller.h>


namespace KDevelop {

class AbstractNavigationContextPrivate
{
public:
  QVector<NavigationContextPointer> m_children; //Used to keep alive all children until this is deleted

  int m_selectedLink = 0; //The link currently selected
  NavigationAction m_selectedLinkAction; //Target of the currently selected link

  bool m_shorten = false;

  //A counter used while building the html-code to count the used links.
  int m_linkCount = -1;
  //Something else than -1 if the current position is represented by a line-number, not a link.
  int m_currentLine = 0;
  int m_currentPositionLine = 0;
  QMap<QString, NavigationAction> m_links;
  QMap<int, int> m_linkLines; //Holds the line for each link
  QMap<int, NavigationAction> m_intLinks;
  AbstractNavigationContext* m_previousContext;
  QString m_prefix, m_suffix;
  TopDUContextPointer m_topContext;

  QString m_currentText; //Here the text is built
};

void AbstractNavigationContext::setTopContext(const TopDUContextPointer& context)
{
  d->m_topContext = context;
}

TopDUContextPointer AbstractNavigationContext::topContext() const
{
  return d->m_topContext;
}

AbstractNavigationContext::AbstractNavigationContext(const TopDUContextPointer& topContext,
                                                     AbstractNavigationContext* previousContext)
  : d(new AbstractNavigationContextPrivate)
{
  d->m_previousContext = previousContext;
  d->m_topContext = topContext;

  qRegisterMetaType<KTextEditor::Cursor>("KTextEditor::Cursor");
  qRegisterMetaType<IDocumentation::Ptr>("IDocumentation::Ptr");
}

AbstractNavigationContext::~AbstractNavigationContext()
{
}

void AbstractNavigationContext::addExternalHtml( const QString& text )
{
  int lastPos = 0;
  int pos = 0;
  QString fileMark = QStringLiteral("KDEV_FILE_LINK{");
  while( pos < text.length() && (pos = text.indexOf( fileMark, pos)) != -1 ) {
    modifyHtml() +=  text.mid(lastPos, pos-lastPos);

    pos += fileMark.length();

    if( pos != text.length() ) {
      int fileEnd = text.indexOf(QLatin1Char('}'), pos);
      if( fileEnd != -1 ) {
        QString file = text.mid( pos, fileEnd - pos );
        pos = fileEnd + 1;
        const QUrl url = QUrl::fromUserInput(file);
        makeLink( url.fileName(), file, NavigationAction( url, KTextEditor::Cursor() ) );
      }
    }

    lastPos = pos;
  }

  modifyHtml() +=  text.mid(lastPos, text.length()-lastPos);
}

void AbstractNavigationContext::makeLink(const QString& name, const DeclarationPointer& declaration, NavigationAction::Type actionType)
{
  NavigationAction action( declaration, actionType );
  makeLink(name, QString(), action);
}

QString AbstractNavigationContext::createLink(const QString& name, const QString&, const NavigationAction& action)
{
  if(d->m_shorten) {
    //Do not create links in shortened mode, it's only for viewing
    return typeHighlight(name.toHtmlEscaped());
  }

  // NOTE: Since the by definition in the HTML standard some uri components
  //       are case-insensitive, we define a new lowercase link-id for each
  //       link. Otherwise Qt 5 seems to mess up the casing and the link
  //       cannot be matched when it's executed.
  QString hrefId = QStringLiteral("link_%1").arg(d->m_links.count());

  d->m_links[ hrefId ] = action;
  d->m_intLinks[ d->m_linkCount ] = action;
  d->m_linkLines[ d->m_linkCount ] = d->m_currentLine;
  if(d->m_currentPositionLine == d->m_currentLine) {
    d->m_currentPositionLine = -1;
    d->m_selectedLink = d->m_linkCount;
  }

  QString str = name.toHtmlEscaped();
  if( d->m_linkCount == d->m_selectedLink )
    str = QLatin1String("<font style=\"background-color:#f1f1f1;\" color=\"#880088\">") + str + QLatin1String("</font>");

  QString ret = QLatin1String("<a href=\"") + hrefId + QLatin1Char('\"') + ((d->m_linkCount == d->m_selectedLink && d->m_currentPositionLine == -1) ? QStringLiteral(" name = \"currentPosition\"") : QString()) + QLatin1Char('>') + str + QLatin1String("</a>");

  if( d->m_selectedLink == d->m_linkCount )
    d->m_selectedLinkAction = action;

  ++d->m_linkCount;
  return ret;
}

void AbstractNavigationContext::makeLink(const QString& name, const QString& targetId, const NavigationAction& action)
{
  modifyHtml() += createLink(name, targetId, action);
}

void AbstractNavigationContext::clear() {
    d->m_linkCount = 0;
    d->m_currentLine = 0;
    d->m_currentText.clear();
    d->m_links.clear();
    d->m_intLinks.clear();
    d->m_linkLines.clear();
}


void AbstractNavigationContext::executeLink(const QString& link)
{
  if(!d->m_links.contains(link))
    return;

  execute(d->m_links[link]);
}

NavigationContextPointer AbstractNavigationContext::executeKeyAction(const QString& key)
{
  Q_UNUSED(key);
  return NavigationContextPointer(this);
}

NavigationContextPointer AbstractNavigationContext::execute(const NavigationAction& action)
{
  if(action.targetContext)
    return NavigationContextPointer(action.targetContext);

  if(action.type == NavigationAction::ExecuteKey)
    return executeKeyAction(action.key);


  if( !action.decl && (action.type != NavigationAction::JumpToSource || action.document.isEmpty()) ) {
      qCDebug(LANGUAGE) << "Navigation-action has invalid declaration" << endl;
      return NavigationContextPointer(this);
  }

  switch( action.type ) {
    case NavigationAction::ExecuteKey:
      break;
    case NavigationAction::None:
      qCDebug(LANGUAGE) << "Tried to execute an invalid action in navigation-widget" << endl;
      break;
    case NavigationAction::NavigateDeclaration:
    {
      auto ctx = dynamic_cast<AbstractDeclarationNavigationContext*>(d->m_previousContext);
      if( ctx && ctx->declaration() == action.decl )
        return NavigationContextPointer(d->m_previousContext);
      return registerChild(action.decl);
    } break;
    case NavigationAction::NavigateUses:
    {
      IContextBrowser* browser = ICore::self()->pluginController()->extensionForPlugin<IContextBrowser>();
      if (browser) {
        browser->showUses(action.decl);
        return NavigationContextPointer(this);
      }
      Q_FALLTHROUGH();
    }
    case NavigationAction::ShowUses: {
      return registerChild(new UsesNavigationContext(action.decl.data(), this));
    }
    case NavigationAction::JumpToSource:
      {
        QUrl doc = action.document;
        KTextEditor::Cursor cursor = action.cursor;
        {
          DUChainReadLocker lock(DUChain::lock());
          if(action.decl) {
            if(doc.isEmpty()) {
              doc = action.decl->url().toUrl();
    /*          if(action.decl->internalContext())
                cursor = action.decl->internalContext()->range().start() + KTextEditor::Cursor(0, 1);
              else*/
                cursor = action.decl->rangeInCurrentRevision().start();
            }

            action.decl->activateSpecialization();
          }
        }

        //This is used to execute the slot delayed in the event-loop, so crashes are avoided
        QMetaObject::invokeMethod( ICore::self()->documentController(), "openDocument", Qt::QueuedConnection, Q_ARG(QUrl, doc), Q_ARG(KTextEditor::Cursor, cursor) );
        break;
      }
    case NavigationAction::ShowDocumentation: {
        auto doc = ICore::self()->documentationController()->documentationForDeclaration(action.decl.data());
        // This is used to execute the slot delayed in the event-loop, so crashes are avoided
        // which can happen e.g. due to focus change events resulting in tooltip destruction and thus this object
        QMetaObject::invokeMethod(ICore::self()->documentationController(), "showDocumentation", Qt::QueuedConnection, Q_ARG(IDocumentation::Ptr, doc));
      }
      break;
  }

  return NavigationContextPointer( this );
}

AbstractNavigationContext* AbstractNavigationContext::previousContext() const
{
  return d->m_previousContext;
}

void AbstractNavigationContext::setPreviousContext(AbstractNavigationContext* previous) {
  d->m_previousContext = previous;
}

NavigationContextPointer AbstractNavigationContext::registerChild(AbstractNavigationContext* context)
{
  d->m_children << NavigationContextPointer(context);
  return d->m_children.last();
}

NavigationContextPointer AbstractNavigationContext::registerChild(const DeclarationPointer& declaration) {
  //We create a navigation-widget here, and steal its context.. evil ;)
  QScopedPointer<QWidget> navigationWidget(declaration->context()->createNavigationWidget(declaration.data()));
  if (AbstractNavigationWidget* abstractNavigationWidget = dynamic_cast<AbstractNavigationWidget*>(navigationWidget.data()) ) {
    NavigationContextPointer ret = abstractNavigationWidget->context();
    ret->setPreviousContext(this);
    d->m_children << ret;
    return ret;
  } else {
    return NavigationContextPointer(this);
  }
}

const int lineJump = 3;

void AbstractNavigationContext::down() {
  //Make sure link-count is valid
  if( d->m_linkCount == -1 ) {
    DUChainReadLocker lock;
    html();
  }

  int fromLine = d->m_currentPositionLine;

  if(d->m_selectedLink >= 0 && d->m_selectedLink < d->m_linkCount) {

    if(fromLine == -1)
      fromLine = d->m_linkLines[d->m_selectedLink];

    for(int newSelectedLink = d->m_selectedLink+1; newSelectedLink < d->m_linkCount; ++newSelectedLink) {
      if(d->m_linkLines[newSelectedLink] > fromLine && d->m_linkLines[newSelectedLink] - fromLine <= lineJump) {
        d->m_selectedLink = newSelectedLink;
        d->m_currentPositionLine = -1;
        return;
      }
    }
  }
  if(fromLine == -1)
    fromLine = 0;

  d->m_currentPositionLine = fromLine + lineJump;

  if(d->m_currentPositionLine > d->m_currentLine)
    d->m_currentPositionLine = d->m_currentLine;
}

void AbstractNavigationContext::up() {
  //Make sure link-count is valid
  if( d->m_linkCount == -1 ) {
    DUChainReadLocker lock;
    html();
  }

  int fromLine = d->m_currentPositionLine;

  if(d->m_selectedLink >= 0 && d->m_selectedLink < d->m_linkCount) {

    if(fromLine == -1)
      fromLine = d->m_linkLines[d->m_selectedLink];

    for(int newSelectedLink = d->m_selectedLink-1; newSelectedLink >= 0; --newSelectedLink) {
      if(d->m_linkLines[newSelectedLink] < fromLine && fromLine - d->m_linkLines[newSelectedLink] <= lineJump) {
        d->m_selectedLink = newSelectedLink;
        d->m_currentPositionLine = -1;
        return;
      }
    }
  }

  if(fromLine == -1)
    fromLine = d->m_currentLine;

  d->m_currentPositionLine = fromLine - lineJump;
  if(d->m_currentPositionLine < 0)
    d->m_currentPositionLine = 0;
}

void AbstractNavigationContext::nextLink()
{
  //Make sure link-count is valid
  if( d->m_linkCount == -1 ) {
    DUChainReadLocker lock;
    html();
  }

  d->m_currentPositionLine = -1;

  if( d->m_linkCount > 0 )
    d->m_selectedLink = (d->m_selectedLink+1) % d->m_linkCount;
}

void AbstractNavigationContext::previousLink()
{
  //Make sure link-count is valid
  if( d->m_linkCount == -1 ) {
    DUChainReadLocker lock;
    html();
  }

  d->m_currentPositionLine = -1;

  if( d->m_linkCount > 0 ) {
    --d->m_selectedLink;
    if( d->m_selectedLink <  0 )
      d->m_selectedLink += d->m_linkCount;
  }

  Q_ASSERT(d->m_selectedLink >= 0);
}

int AbstractNavigationContext::linkCount() const
{
  return d->m_linkCount;
}

QString AbstractNavigationContext::prefix() const
{
  return d->m_prefix;
}

QString AbstractNavigationContext::suffix() const
{
  return d->m_suffix;
}

void AbstractNavigationContext::setPrefixSuffix( const QString& prefix, const QString& suffix )
{
  d->m_prefix = prefix;
  d->m_suffix = suffix;
}

NavigationContextPointer AbstractNavigationContext::back() {
  if(d->m_previousContext)
    return NavigationContextPointer(d->m_previousContext);
  else
    return NavigationContextPointer(this);
}

NavigationContextPointer AbstractNavigationContext::accept() {
  if( d->m_selectedLink >= 0 &&  d->m_selectedLink < d->m_linkCount )
  {
    NavigationAction action = d->m_intLinks[d->m_selectedLink];
    return execute(action);
  }
  return NavigationContextPointer(this);
}

NavigationContextPointer AbstractNavigationContext::accept(IndexedDeclaration decl) {
  if(decl.data()) {
    NavigationAction action(DeclarationPointer(decl.data()), NavigationAction::NavigateDeclaration);
    return execute(action);
  }else{
    return NavigationContextPointer(this);
  }
}

NavigationContextPointer AbstractNavigationContext::acceptLink(const QString& link) {
  if( !d->m_links.contains(link) ) {
    qCDebug(LANGUAGE) << "Executed unregistered link " << link << endl;
    return NavigationContextPointer(this);
  }

  return execute(d->m_links[link]);
}


NavigationAction AbstractNavigationContext::currentAction() const {
  return d->m_selectedLinkAction;
}


QString AbstractNavigationContext::declarationKind(const DeclarationPointer& decl)
{
  const AbstractFunctionDeclaration* function = dynamic_cast<const AbstractFunctionDeclaration*>(decl.data());

  QString kind;

  if( decl->isTypeAlias() )
    kind = i18n("Typedef");
  else if( decl->kind() == Declaration::Type ) {
    if( decl->type<StructureType>() )
      kind = i18n("Class");
  } else if( decl->kind() == Declaration::Instance ) {
    kind = i18n("Variable");
  } else if ( decl->kind() == Declaration::Namespace ) {
    kind = i18n("Namespace");
  }

  if( NamespaceAliasDeclaration* alias = dynamic_cast<NamespaceAliasDeclaration*>(decl.data()) ) {
    if( alias->identifier().isEmpty() )
      kind = i18n("Namespace import");
    else
      kind = i18n("Namespace alias");
  }

  if(function)
    kind = i18n("Function");

  if( decl->isForwardDeclaration() )
    kind = i18n("Forward Declaration");

  return kind;
}

QString AbstractNavigationContext::html(bool shorten) {
  d->m_shorten = shorten;
  return QString();
}

bool AbstractNavigationContext::alreadyComputed() const {
  return !d->m_currentText.isEmpty();
}

bool AbstractNavigationContext::isWidgetMaximized() const
{
  return true;
}

QWidget* AbstractNavigationContext::widget() const {
  return nullptr;
}

///Splits the string by the given regular expression, but keeps the split-matches at the end of each line
static QStringList splitAndKeep(QString str, const QRegExp& regExp) {
  QStringList ret;
  int place = regExp.indexIn(str);
  while(place != -1) {
    ret << str.left(place + regExp.matchedLength());
    str.remove(0, place + regExp.matchedLength());
    place = regExp.indexIn(str);
  }
  ret << str;
  return ret;
}

void AbstractNavigationContext::addHtml(const QString& html) {
  QRegExp newLineRegExp(QStringLiteral("<br>|<br */>"));
  foreach(const QString& line, splitAndKeep(html, newLineRegExp)) {
    d->m_currentText +=  line;
    if(line.indexOf(newLineRegExp) != -1) {
      ++d->m_currentLine;
      if(d->m_currentLine == d->m_currentPositionLine) {
        d->m_currentText += QStringLiteral("<font color=\"#880088\"> <a name = \"currentPosition\" >&lt;-&gt;</a> </font>"); // >&lt;-&gt; is <->
      }
    }
  }
}

QString AbstractNavigationContext::currentHtml() const {
    return d->m_currentText;
}

QString AbstractNavigationContext::fontSizePrefix(bool /*shorten*/) const
{
  return QString();
}

QString AbstractNavigationContext::fontSizeSuffix(bool /*shorten*/) const
{
  return QString();
}

QString Colorizer::operator() ( const QString& str ) const
{
  QString ret = QLatin1String("<font color=\"#") + m_color + QLatin1String("\">") + str + QLatin1String("</font>");

  if( m_formatting & Fixed )
    ret = QLatin1String("<tt>") + ret + QLatin1String("</tt>");
  if ( m_formatting & Bold )
    ret = QLatin1String("<b>") + ret + QLatin1String("</b>");
  if ( m_formatting & Italic )
    ret = QLatin1String("<i>") + ret + QLatin1String("</i>");

  return ret;
}

const Colorizer AbstractNavigationContext::typeHighlight(QStringLiteral("006000"));
const Colorizer AbstractNavigationContext::errorHighlight(QStringLiteral("990000"));
const Colorizer AbstractNavigationContext::labelHighlight(QStringLiteral("000000"));
const Colorizer AbstractNavigationContext::codeHighlight(QStringLiteral("005000"));
const Colorizer AbstractNavigationContext::propertyHighlight(QStringLiteral("009900"));
const Colorizer AbstractNavigationContext::navigationHighlight(QStringLiteral("000099"));
const Colorizer AbstractNavigationContext::importantHighlight(QStringLiteral("000000"), Colorizer::Bold | Colorizer::Italic);
const Colorizer AbstractNavigationContext::commentHighlight(QStringLiteral("303030"));
const Colorizer AbstractNavigationContext::nameHighlight(QStringLiteral("000000"), Colorizer::Bold);

}
