#include "../include/ChatWindow.hpp"
#include "../include/ChatMessage.hpp"
#include "../include/InputDialog.hpp"
#include "../include/Window.hpp"
#include <gtkmm/alignment.h>
#include <gtkmm/viewport.h>
#include <gtkmm/scrollbar.h>
#include <gtkmm/eventbox.h>
#include <assert.h>

namespace dchat
{
    // Merge all messages that are written by the same user without interrupt within a timeframe
    const int MERGE_MESSAGE_TIMESTAMP_DIFF_SEC = 60;

    ChatWindow::ChatWindow(Window *_window) : 
        addRoomButton("images/add_button_small.png", "  Add room"),
        roomCount(0),
        currentRoomData(nullptr),
        window(_window)
    {
        assert(window);
        leftPanelUsersStack.set_homogeneous(false);
        messageAreaStack.set_homogeneous(false);
        setupTopBar();

        Gtk::Paned *sidePanels = Gtk::manage(new Gtk::Paned());
        sidePanels->set_name("side-panels");
        sidePanels->set_border_width(0);
        attach(*sidePanels, 0, 1, 1, 2);

        setupLeftPanel(sidePanels);

        Gtk::Grid *rightPanel = Gtk::manage(new Gtk::Grid());
        rightPanel->set_vexpand(true);
        rightPanel->set_hexpand(true);
        sidePanels->add2(*rightPanel);

        setupMessageArea(rightPanel);
        setupChatInput(rightPanel);

        set_vexpand(true);
        set_hexpand(true);
    }

    ChatWindow::~ChatWindow()
    {
        for(auto &it : roomDataById)
        {
            delete it.second->leftPanelUsersLayout;
            delete it.second->messageAreaLayout;
            delete it.second->button;
            delete it.second;
        }
    }

    void ChatWindow::setupTopBar()
    {
        topbar.set_name("top-bar");
        topbar.set_hexpand(true);
        attach(topbar, 0, 0, 2, 1);

        Gtk::Grid *topbarLeft = Gtk::manage(new Gtk::Grid());
        topbarLeft->set_name("top-bar-left");
        topbarLeft->set_size_request(180);
        topbarLeft->set_valign(Gtk::ALIGN_CENTER);
        topbarLeft->set_halign(Gtk::ALIGN_CENTER);
        topbar.attach(*topbarLeft, 0, 0, 1, 1);

        topbarSearchBar.set_name("top-bar-search");
        topbarSearchBar.set_placeholder_text("Search...");
        topbarSearchBar.set_size_request(180);
        topbarLeft->attach(topbarSearchBar, 0, 0, 1, 1);

        Gtk::Grid *topbarRight = Gtk::manage(new Gtk::Grid());
        topbarRight->set_name("top-bar-right");
        topbarRight->set_hexpand(true);
        topbarRight->set_valign(Gtk::ALIGN_CENTER);
        topbar.attach_next_to(*topbarRight, *topbarLeft, Gtk::POS_RIGHT, 1, 1);

        currentChannelTitle.set_name("current-room-title");
        currentChannelTitle.set_hexpand(true);
        currentChannelTitle.set_alignment(Gtk::ALIGN_START, Gtk::ALIGN_CENTER);
        topbarRight->attach(currentChannelTitle, 0, 0, 1, 1);

        ImageButton *channelSettings = Gtk::manage(new ImageButton("images/settings-icon.png", nullptr));
        topbarRight->attach_next_to(*channelSettings, currentChannelTitle, Gtk::POS_RIGHT, 1, 1);
    }

    void ChatWindow::setupLeftPanel(Gtk::Paned *sidePanels)
    {
        Gtk::Grid *leftPanelLayout = Gtk::manage(new Gtk::Grid());
        leftPanelLayout->set_vexpand(true);
        leftPanelLayout->set_size_request(200);
        leftPanelLayout->set_name("left-panel");
        sidePanels->add1(*leftPanelLayout);

        Gtk::Paned *leftPanel = Gtk::manage(new Gtk::Paned(Gtk::ORIENTATION_VERTICAL));
        leftPanel->set_vexpand(true);
        leftPanelLayout->attach(*leftPanel, 0, 0, 1, 2);

        leftPanelChannels.set_vexpand(true);
        leftPanel->add1(leftPanelChannels);

        Gtk::Label *channelsTitle = Gtk::manage(new Gtk::Label());
        channelsTitle->set_name("channels-title");
        channelsTitle->set_text("Channels");
        channelsTitle->set_halign(Gtk::ALIGN_START);
        leftPanelChannels.attach(*channelsTitle, 0, 0, 1, 1);

        ////
        leftPanelUsersStack.set_vexpand(true);
        leftPanel->add2(leftPanelUsersStack);

        addRoomButton.set_halign(Gtk::ALIGN_START);
        leftPanelLayout->attach_next_to(addRoomButton, *leftPanel, Gtk::POS_BOTTOM, 1, 1);
        addRoomButton.signal_clicked().connect([this]()
        {
            InputDialog createRoomDialog("Create a new room", "Room name");
            switch(createRoomDialog.run())
            {
                case Gtk::RESPONSE_ACCEPT:
                {
                    // TODO: Show error inline in the create room dialog
                    Glib::ustring roomName = createRoomDialog.getInput();
                    if(roomName.size() == 0 || roomName.size() > 32)
                        window->windowNotification->show("Room name has to be between 1 and 32 characters");
                    else
                        window->rooms->createRoom(roomName);
                    break;
                }
                default:
                    break;
            }
        });
    }

    void ChatWindow::setupMessageArea(Gtk::Grid *rightPanel)
    {
        //messageArea.set_valign(Gtk::ALIGN_START);
        messageArea.set_vexpand(true);
        messageArea.set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_AUTOMATIC);
        rightPanel->attach(messageArea, 0, 0, 1, 2);

        messageAreaStack.set_name("chat-area-layout");
        messageArea.add(messageAreaStack);
    }

    void ChatWindow::setupChatInput(Gtk::Grid *rightPanel)
    {
        Gtk::Grid *chatArea = Gtk::manage(new Gtk::Grid());
        rightPanel->attach_next_to(*chatArea, messageArea, Gtk::POS_BOTTOM, 1, 1);

        Gtk::ScrolledWindow *chatScrollWindow = Gtk::manage(new Gtk::ScrolledWindow());
        chatScrollWindow->set_hexpand(true);
        chatScrollWindow->set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_NEVER);
        chatScrollWindow->set_name("chat-scroll-view");
        chatArea->attach(*chatScrollWindow, 0, 0, 1, 1);

        chatInput.set_hexpand(true);
        chatInput.set_editable(false);
        chatInput.set_name("chat-input");
        chatInput.set_wrap_mode(Gtk::WrapMode::WRAP_WORD_CHAR);
        chatScrollWindow->add(chatInput);

        double fontSize = 18.5;//PANGO_PIXELS(chatInput.get_style_context()->get_font().get_size());
        chatPrevNumLines = 1;
        chatInput.signal_key_press_event().connect([this](GdkEventKey *event)
        {
            if((event->keyval == GDK_KEY_Return || event->keyval == GDK_KEY_KP_Enter) && !(event->state & Gdk::SHIFT_MASK))
            {
                if(chatInput.get_editable())
                {
                    currentRoom->publishMessage(chatInput.get_buffer()->get_text());
                    chatInput.get_buffer()->set_text("");
                }
                return true;
            }
            return false;
        }, false);
        chatInput.get_buffer()->signal_changed().connect([this, chatScrollWindow, fontSize]
        {
            int numLines = chatInput.get_buffer()->get_line_count();
            numLines = std::min(numLines, 10);
            if(numLines != chatPrevNumLines)
            {
                chatPrevNumLines = numLines;
                chatScrollWindow->set_min_content_height(fontSize * numLines);

                auto adj = chatScrollWindow->get_vadjustment();
                if(chatInput.get_buffer()->get_line_count() <= 10)
                {
                    chatScrollWindow->set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_NEVER);
                    adj->set_value(0);
                }
                else
                {
                    chatScrollWindow->set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_ALWAYS);
                }
            }
        });
        chatScrollWindow->get_vadjustment()->signal_value_changed().connect([this, chatScrollWindow]()
        {
            auto adj = chatScrollWindow->get_vadjustment();
            if(chatInput.get_buffer()->get_line_count() <= 11)
            {
                chatScrollWindow->set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_NEVER);
                adj->set_value(0);
            }
            else
            {
                chatScrollWindow->set_policy(Gtk::PolicyType::POLICY_NEVER, Gtk::PolicyType::POLICY_ALWAYS);
            }
        });
    }

    void ChatWindow::addRoom(std::shared_ptr<Room> room)
    {
        std::string roomIdStr = room->id->toString();
        Gtk::Grid *leftPanelUsersLayout = new Gtk::Grid();
        leftPanelUsersLayout->set_vexpand(true);
        leftPanelUsersLayout->show();
        leftPanelUsersStack.add(*leftPanelUsersLayout, roomIdStr);

        Gtk::Label *usersTitle = Gtk::manage(new Gtk::Label());
        usersTitle->get_style_context()->add_class("users-title");
        usersTitle->set_text("Users");
        usersTitle->set_halign(Gtk::ALIGN_START);
        usersTitle->show();
        leftPanelUsersLayout->attach(*usersTitle, 0, 0, 1, 1);

        Gtk::Grid *messageAreaLayout = new Gtk::Grid();
        messageAreaLayout->show();
        messageAreaStack.add(*messageAreaLayout, roomIdStr);

        fprintf(stderr, "Added channel %s\n", room->id->toString().c_str());
        Gtk::ToggleButton *roomButton = new Gtk::ToggleButton("Room name");
        roomButton->set_active(true);
        roomButton->get_style_context()->add_class("room-button");
        roomButton->set_hexpand(true);
        roomButton->set_halign(Gtk::ALIGN_START);
        roomButton->get_child()->set_halign(Gtk::ALIGN_START);
        roomButton->show();
        roomButton->signal_clicked().connect([this, room]
        {
            setCurrentRoom(room);
        });
        leftPanelChannels.attach(*roomButton, 0, 1 + roomCount, 1, 1);
        ++roomCount;
        currentRoomData = new RoomData { leftPanelUsersLayout, messageAreaLayout, roomButton };
        roomDataById[*room->id] = currentRoomData;
        currentRoom = room;
        chatInput.set_editable(true);

        leftPanelUsersStack.set_visible_child(roomIdStr);
        messageAreaStack.set_visible_child(roomIdStr);
    }

    void ChatWindow::setCurrentRoom(std::shared_ptr<Room> room)
    {
        std::string roomIdStr = room->id->toString();
        leftPanelUsersStack.set_visible_child(roomIdStr);
        messageAreaStack.set_visible_child(roomIdStr);
        currentChannelTitle.set_text(room->name);
        currentRoom = room;
        currentRoomData = roomDataById[*room->id];
        chatInput.set_editable(true);

        // TODO: Instead of scrolling to bottom, remember scroll position (even after restarting application).
        // We want to show oldest unread message first
        scrollToBottom();
    }

    void ChatWindow::addMessage(const RoomAddMessageRequest &request)
    {
        auto roomMessages = request.room->messages;
        RoomMessage *lastMessage = nullptr;
        if(!roomMessages.empty())
            lastMessage = &roomMessages.back();

        if(lastMessage && lastMessage->creator->publicKey == request.message.creator->publicKey)
        {
            int64_t msgTimeDiff = (int64_t)request.message.timestampSeconds - (int64_t)lastMessage->timestampSeconds;
            if(msgTimeDiff <= MERGE_MESSAGE_TIMESTAMP_DIFF_SEC)
            {
                auto message = messageById[lastMessage->id];
                message->text.set_text(message->text.get_text() + "\n" + request.message.text);
                // Since messages that are sent withing a timeframe are combined, several message ids can refer to the same message
                messageById[request.message.id] = message;
                if(!request.loadedFromCache && *request.room->id == *currentRoom->id)
                {
                    currentRoomData->messageAreaLayout->queue_draw();
                    scrollToBottom();
                }
                return;
            }
        }

        std::string userNickname = request.message.creator->nickname;
        if(userNickname.empty())
            userNickname = "Anonymous";
        ChatMessage *message = Gtk::manage(new ChatMessage(userNickname, request.message.text, request.message.timestampSeconds));
        message->set_valign(Gtk::Align::ALIGN_START);
        message->set_hexpand(true);
        message->show_all();
        messageById[request.message.id] = message;
        RoomData *roomData = roomDataById[*request.room->id];
        roomData->messageAreaLayout->attach(*message, 0, roomMessages.size(), 1, 1);

        // TODO: When we get a message in the current room we scroll to the bottom, but this should only be done if we are not manually scrolling to view old messages
        if(!request.loadedFromCache && *request.room->id == *currentRoom->id)
        {
            roomData->messageAreaLayout->queue_draw();
            scrollToBottom();
        }
    }

    void ChatWindow::addUser(std::shared_ptr<Room> room, std::shared_ptr<User> user)
    {
        Gtk::Label *username = Gtk::manage(new Gtk::Label("Anonymous"));
        username->set_halign(Gtk::ALIGN_START);
        username->show();
        username->get_style_context()->add_class("username-list-username");
        user->userdata = username;
        RoomData *roomData = roomDataById[*room->id];
        roomData->leftPanelUsersLayout->attach(*username, 0, room->userByPublicKey.size(), 1, 1);
        fprintf(stderr, "Added user %s\n", user->publicKey.toString().c_str());
    }

    void ChatWindow::setUserNickname(const UserChangeNicknameRequest &request)
    {
        Gtk::Label *userNicknameLabel = (Gtk::Label*)request.user->userdata;
        userNicknameLabel->set_text(request.newNickname);
        fprintf(stderr, "Set nickname for user %s to %s\n", request.user->publicKey.toString().c_str(), request.newNickname.c_str());
    }

    void ChatWindow::changeRoomName(const RoomChangeNameRequest &request)
    {
        Gtk::Button *button = roomDataById[*request.room->id]->button;
        static_cast<Gtk::Label*>(button->get_child())->set_text(request.newName);
        if(*request.room->id == *currentRoom->id)
            currentChannelTitle.set_text(request.newName);
        fprintf(stderr, "Changed room %s name to %s\n", request.room->id->toString().c_str(), request.newName.c_str());
    }

    void ChatWindow::scrollToBottom()
    {
        while(gtk_events_pending())
            gtk_main_iteration_do(FALSE);
        auto adj = messageArea.get_vadjustment();
        adj->set_value(adj->get_upper());
    }
}