/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2017 - ROLI Ltd.

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

#include "../Application/jucer_Headers.h"
#include "jucer_OpenDocumentManager.h"
#include "../CodeEditor/jucer_ItemPreviewComponent.h"
#include "../Application/jucer_Application.h"


//==============================================================================
class UnknownDocument  : public OpenDocumentManager::Document
{
public:
    UnknownDocument (Project* p, const File& f)
       : project (p), file (f)
    {
        reloadFromFile();
    }

    //==============================================================================
    struct Type  : public OpenDocumentManager::DocumentType
    {
        bool canOpenFile (const File&) override                     { return true; }
        Document* openFile (Project* p, const File& f) override     { return new UnknownDocument (p, f); }
    };

    //==============================================================================
    bool loadedOk() const override                           { return true; }
    bool isForFile (const File& f) const override            { return file == f; }
    bool isForNode (const ValueTree&) const override         { return false; }
    bool refersToProject (Project& p) const override         { return project == &p; }
    Project* getProject() const override                     { return project; }
    bool needsSaving() const override                        { return false; }
    bool save() override                                     { return true; }
    bool saveAs() override                                   { return false; }
    bool hasFileBeenModifiedExternally() override            { return fileModificationTime != file.getLastModificationTime(); }
    void reloadFromFile() override                           { fileModificationTime = file.getLastModificationTime(); }
    String getName() const override                          { return file.getFileName(); }
    File getFile() const override                            { return file; }
    Component* createEditor() override                       { return new ItemPreviewComponent (file); }
    Component* createViewer() override                       { return createEditor(); }
    void fileHasBeenRenamed (const File& newFile) override   { file = newFile; }
    String getState() const override                         { return {}; }
    void restoreState (const String&) override               {}

    String getType() const override
    {
        if (file.getFileExtension().isNotEmpty())
            return file.getFileExtension() + " file";

        jassertfalse;
        return "Unknown";
    }

private:
    Project* const project;
    File file;
    Time fileModificationTime;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (UnknownDocument)
};


//==============================================================================
OpenDocumentManager::DocumentType* createGUIDocumentType();

OpenDocumentManager::OpenDocumentManager()
{
    registerType (new UnknownDocument::Type());
    registerType (new SourceCodeDocument::Type());
    registerType (createGUIDocumentType());
}

OpenDocumentManager::~OpenDocumentManager()
{
}

void OpenDocumentManager::clear()
{
    documents.clear();
    types.clear();
}

//==============================================================================
void OpenDocumentManager::registerType (DocumentType* type, int index)
{
    types.insert (index, type);
}

//==============================================================================
void OpenDocumentManager::addListener (DocumentCloseListener* listener)
{
    listeners.addIfNotAlreadyThere (listener);
}

void OpenDocumentManager::removeListener (DocumentCloseListener* listener)
{
    listeners.removeFirstMatchingValue (listener);
}

//==============================================================================
bool OpenDocumentManager::canOpenFile (const File& file)
{
    for (int i = types.size(); --i >= 0;)
        if (types.getUnchecked(i)->canOpenFile (file))
            return true;

    return false;
}

OpenDocumentManager::Document* OpenDocumentManager::openFile (Project* project, const File& file)
{
    for (int i = documents.size(); --i >= 0;)
        if (documents.getUnchecked(i)->isForFile (file))
            return documents.getUnchecked(i);

    Document* d = nullptr;

    for (int i = types.size(); --i >= 0 && d == nullptr;)
    {
        if (types.getUnchecked(i)->canOpenFile (file))
        {
            d = types.getUnchecked(i)->openFile (project, file);
            jassert (d != nullptr);
        }
    }

    jassert (d != nullptr);  // should always at least have been picked up by UnknownDocument

    documents.add (d);
    ProjucerApplication::getCommandManager().commandStatusChanged();
    return d;
}

int OpenDocumentManager::getNumOpenDocuments() const
{
    return documents.size();
}

OpenDocumentManager::Document* OpenDocumentManager::getOpenDocument (int index) const
{
    return documents.getUnchecked (index);
}

FileBasedDocument::SaveResult OpenDocumentManager::saveIfNeededAndUserAgrees (OpenDocumentManager::Document* doc)
{
    if (! doc->needsSaving())
        return FileBasedDocument::savedOk;

    const int r = AlertWindow::showYesNoCancelBox (AlertWindow::QuestionIcon,
                                                   TRANS("Closing document..."),
                                                   TRANS("Do you want to save the changes to \"")
                                                       + doc->getName() + "\"?",
                                                   TRANS("Save"),
                                                   TRANS("Discard changes"),
                                                   TRANS("Cancel"));

    if (r == 1)  // save changes
        return doc->save() ? FileBasedDocument::savedOk
                           : FileBasedDocument::failedToWriteToFile;

    if (r == 2)  // discard changes
        return FileBasedDocument::savedOk;

    return FileBasedDocument::userCancelledSave;
}


bool OpenDocumentManager::closeDocument (int index, bool saveIfNeeded)
{
    if (Document* doc = documents [index])
    {
        if (saveIfNeeded)
            if (saveIfNeededAndUserAgrees (doc) != FileBasedDocument::savedOk)
                return false;

        bool canClose = true;

        for (int i = listeners.size(); --i >= 0;)
            if (DocumentCloseListener* l = listeners[i])
                if (! l->documentAboutToClose (doc))
                    canClose = false;

        if (! canClose)
            return false;

        documents.remove (index);
        ProjucerApplication::getCommandManager().commandStatusChanged();
    }

    return true;
}

bool OpenDocumentManager::closeDocument (Document* document, bool saveIfNeeded)
{
    return closeDocument (documents.indexOf (document), saveIfNeeded);
}

void OpenDocumentManager::closeFile (const File& f, bool saveIfNeeded)
{
    for (int i = documents.size(); --i >= 0;)
        if (Document* d = documents[i])
            if (d->isForFile (f))
                closeDocument (i, saveIfNeeded);
}

bool OpenDocumentManager::closeAll (bool askUserToSave)
{
    for (int i = getNumOpenDocuments(); --i >= 0;)
        if (! closeDocument (i, askUserToSave))
            return false;

    return true;
}

bool OpenDocumentManager::closeAllDocumentsUsingProject (Project& project, bool saveIfNeeded)
{
    for (int i = documents.size(); --i >= 0;)
        if (Document* d = documents[i])
            if (d->refersToProject (project))
                if (! closeDocument (i, saveIfNeeded))
                    return false;

    return true;
}

bool OpenDocumentManager::anyFilesNeedSaving() const
{
    for (int i = documents.size(); --i >= 0;)
        if (documents.getUnchecked (i)->needsSaving())
            return true;

    return false;
}

bool OpenDocumentManager::saveAll()
{
    for (int i = documents.size(); --i >= 0;)
    {
        if (! documents.getUnchecked (i)->save())
            return false;

        ProjucerApplication::getCommandManager().commandStatusChanged();
    }

    return true;
}

void OpenDocumentManager::reloadModifiedFiles()
{
    for (int i = documents.size(); --i >= 0;)
    {
        Document* d = documents.getUnchecked (i);

        if (d->hasFileBeenModifiedExternally())
            d->reloadFromFile();
    }
}

void OpenDocumentManager::fileHasBeenRenamed (const File& oldFile, const File& newFile)
{
    for (int i = documents.size(); --i >= 0;)
    {
        Document* d = documents.getUnchecked (i);

        if (d->isForFile (oldFile))
            d->fileHasBeenRenamed (newFile);
    }
}


//==============================================================================
RecentDocumentList::RecentDocumentList()
{
    ProjucerApplication::getApp().openDocumentManager.addListener (this);
}

RecentDocumentList::~RecentDocumentList()
{
    ProjucerApplication::getApp().openDocumentManager.removeListener (this);
}

void RecentDocumentList::clear()
{
    previousDocs.clear();
    nextDocs.clear();
}

void RecentDocumentList::newDocumentOpened (OpenDocumentManager::Document* document)
{
    if (document != nullptr && document != getCurrentDocument())
    {
        nextDocs.clear();
        previousDocs.add (document);
    }
}

bool RecentDocumentList::canGoToPrevious() const
{
    return previousDocs.size() > 1;
}

bool RecentDocumentList::canGoToNext() const
{
    return nextDocs.size() > 0;
}

OpenDocumentManager::Document* RecentDocumentList::getPrevious()
{
    if (! canGoToPrevious())
        return nullptr;

    nextDocs.insert (0, previousDocs.removeAndReturn (previousDocs.size() - 1));
    return previousDocs.getLast();
}

OpenDocumentManager::Document* RecentDocumentList::getNext()
{
    if (! canGoToNext())
        return nullptr;

    OpenDocumentManager::Document* d = nextDocs.removeAndReturn (0);
    previousDocs.add (d);
    return d;
}

bool RecentDocumentList::contains (const File& f) const
{
    for (int i = previousDocs.size(); --i >= 0;)
        if (previousDocs.getUnchecked(i)->getFile() == f)
            return true;

    return false;
}

OpenDocumentManager::Document* RecentDocumentList::getClosestPreviousDocOtherThan (OpenDocumentManager::Document* oneToAvoid) const
{
    for (int i = previousDocs.size(); --i >= 0;)
        if (previousDocs.getUnchecked(i) != oneToAvoid)
            return previousDocs.getUnchecked(i);

    return nullptr;
}

bool RecentDocumentList::documentAboutToClose (OpenDocumentManager::Document* document)
{
    previousDocs.removeAllInstancesOf (document);
    nextDocs.removeAllInstancesOf (document);

    jassert (! previousDocs.contains (document));
    jassert (! nextDocs.contains (document));

    return true;
}

static void restoreDocList (Project& project, Array <OpenDocumentManager::Document*>& list, const XmlElement* xml)
{
    if (xml != nullptr)
    {
        OpenDocumentManager& odm = ProjucerApplication::getApp().openDocumentManager;

        forEachXmlChildElementWithTagName (*xml, e, "DOC")
        {
            const File file (e->getStringAttribute ("file"));

            if (file.exists())
            {
                if (OpenDocumentManager::Document* doc = odm.openFile (&project, file))
                {
                    doc->restoreState (e->getStringAttribute ("state"));

                    list.add (doc);
                }
            }
        }
    }
}

void RecentDocumentList::restoreFromXML (Project& project, const XmlElement& xml)
{
    clear();

    if (xml.hasTagName ("RECENT_DOCUMENTS"))
    {
        restoreDocList (project, previousDocs, xml.getChildByName ("PREVIOUS"));
        restoreDocList (project, nextDocs,     xml.getChildByName ("NEXT"));
    }
}

static void saveDocList (const Array <OpenDocumentManager::Document*>& list, XmlElement& xml)
{
    for (int i = 0; i < list.size(); ++i)
    {
        const OpenDocumentManager::Document& doc = *list.getUnchecked(i);

        XmlElement* e = xml.createNewChildElement ("DOC");

        e->setAttribute ("file", doc.getFile().getFullPathName());
        e->setAttribute ("state", doc.getState());
    }
}

std::unique_ptr<XmlElement> RecentDocumentList::createXML() const
{
    auto xml = std::make_unique<XmlElement> ("RECENT_DOCUMENTS");

    saveDocList (previousDocs, *xml->createNewChildElement ("PREVIOUS"));
    saveDocList (nextDocs,     *xml->createNewChildElement ("NEXT"));

    return xml;
}