#include "githandler.h"

#include <QDebug>
#include <QUrl>
#include <QFileSystemWatcher>
#include <QGuiApplication>
#include <QClipboard>
#include <qqml.h>

#include <gitrepository.h>
#include <gitbranch.h>
#include <gitdiff.h>
#include <commitmodel.h>
#include <tagmodel.h>
#include <git2.h>

#include <colorhandler.h>
#include <commitgraph.h>
#include <graphpoint.h>
#include <branchlistmodel.h>
#include <taglistmodel.h>
#include <gitconsole.h>
#include <graphpoint.h>

GitHandler::GitHandler() : QObject()
  ,m_repositories(new RepositoryModel(this))
  ,m_commits(nullptr)
  ,m_graph(nullptr)
  ,m_activeRepo(nullptr)
  ,m_activeDiff(nullptr)
  ,m_branchList(new BranchListModel(this))
  ,m_tagList(new TagListModel(this))
  ,m_activeRepoWatcher(new QFileSystemWatcher(this))
  ,m_console(new GitConsole(this))
{
    git_libgit2_init();
}

GitHandler::~GitHandler()
{
    git_libgit2_shutdown();
}

void GitHandler::open(const QUrl &url)
{
    if(url.isLocalFile()) {
        open(url.toLocalFile());
    }
}

void GitHandler::open(const QString &path)
{
    qDebug() << "path" << path;
    git_buf root = {0,0,0};
    if(git_repository_discover(&root, path.toUtf8().data(), 0, NULL) != 0) {
        qDebug() << lastError();
        return;
    }

    if(m_activeRepo) {
        m_activeRepoWatcher->removePath(m_activeRepo->root());
    }

    m_activeRepo = new GitRepository(QString::fromUtf8(root.ptr, root.size));
    if(!m_activeRepo->isValid()) {
        qDebug() << lastError();
        return;
    }
    ColorHandler::instance().updateColors(m_activeRepo);
    m_constantHead = m_activeRepo->head();
    m_console->setRepository(m_activeRepo);

    connect(m_activeRepo, &GitRepository::branchesChanged, this, &GitHandler::updateModels);
    updateModels();

    m_activeRepoWatcher->addPath(m_activeRepo->root());
    connect(m_activeRepoWatcher, &QFileSystemWatcher::directoryChanged, m_activeRepo, &GitRepository::readBranches);
    connect(m_activeRepoWatcher, &QFileSystemWatcher::directoryChanged, m_activeRepo, &GitRepository::readRemotes);
    connect(m_activeRepoWatcher, &QFileSystemWatcher::directoryChanged, m_activeRepo, &GitRepository::readTags);
    connect(m_activeRepoWatcher, &QFileSystemWatcher::directoryChanged, this, &GitHandler::updateModels);
    //TODO: opened repositories configuraion TBD
    //    m_repositories->add(m_activeRepo);
}

QString GitHandler::lastError() const
{
    const git_error *e = giterr_last();
    if(e) {
        return QString("(%1): %2").arg(e->klass).arg(e->message);
        giterr_clear();
    }
    giterr_clear();
    return QString();
}

GitDiff* GitHandler::diff(GitCommit* a, GitCommit* b)
{
    if(!m_activeDiff.isNull()) {
        m_activeDiff->deleteLater();
    }

    Q_ASSERT_X(a->repository() == b->repository(), "GitHandler", "Cross repository diff requested");

    m_activeDiff = GitDiff::diff(a, b);
    return m_activeDiff.data();
}

GitDiff* GitHandler::diff()
{
    if(!m_activeDiff.isNull()) {
        m_activeDiff->deleteLater();
    }

    QScopedPointer<GitCommit> commit(GitCommit::fromOid(activeRepo()->head()));
    m_activeDiff = GitDiff::diff(commit.data());
    return m_activeDiff.data();
}


void GitHandler::setActiveDiff(GitDiff* activeDiff)
{
    if (m_activeDiff == activeDiff)
        return;

    m_activeDiff = activeDiff;
    emit activeDiffChanged(activeDiff);
}

GitDiff* GitHandler::activeDiff() const
{
    return m_activeDiff.data();
}

void GitHandler::pull() const
{
    //    git_remote_fetch(m_activeRepo->remote)
}

void GitHandler::updateModels()
{
    if(!m_activeRepo) {
        return;
    }
    m_activeRepo->updateHead();

    BranchContainer &branches = m_activeRepo->branches();
    CommitGraph* graph = new CommitGraph();

    bool headIsBranch = false;
    //TODO: Need to think about constant head more deeply
//    foreach(GitBranch* branch, branches) {
//        if(branch->oid() == m_constantHead) {
//            graph->addHead(branch);
//            headIsBranch = true;
//            break;
//        }
//    }

    if(!headIsBranch) {
        graph->addHead(m_activeRepo->head());
    }

    foreach(GitBranch* branch, branches) {
        qDebug() << "Next head " << branch->fullName();
        graph->addHead(branch);
    }
    graph->addWorkdir();

    m_graph->deleteLater();
    m_graph = graph;
    emit graphChanged(graph);

    m_commits = CommitModel::fromGraph(m_graph);
    emit commitsChanged(m_commits);

    m_branchList->reset(m_activeRepo->branches().values());
    m_tagList->reset(m_activeRepo->tags().values());
}

void GitHandler::copy(const QString& sha1)
{
    QGuiApplication::clipboard()->setText(sha1);
}