#include "messagelist.h"
#include "chatview.h"
#include "messagedelegate.h"
#include "inputbar.h"
#include "emojipanel.h"
#include "emoji.h"
#include "animtimer.h"
#include "lottieicon.h"
#include "../db/db_manager.h"
#include "../transport/chat_propagator.h"
#include <QVBoxLayout>
#include <QPainter>
#include <QPixmap>
#include <QDateTime>
#include <QFile>
#include <vector>
#include <memory>

static QPixmap makeAvatar(const QColor &color, const QString &letter, int size = 36) {
    QPixmap pix(size, size);
    pix.fill(Qt::transparent);
    QPainter p(&pix);
    p.setRenderHint(QPainter::Antialiasing);
    p.setBrush(color);
    p.setPen(Qt::NoPen);
    p.drawEllipse(0, 0, size, size);
    p.setPen(Qt::white);
    QFont f = p.font();
    f.setBold(true);
    f.setPointSize(size / 3);
    p.setFont(f);
    p.drawText(QRect(0, 0, size, size), Qt::AlignCenter, letter);
    p.end();
    return pix;
}

static QVariant makeReaction(const QString &emoji, int count,
                             const QList<QColor> &colors = {}) {
    QVariantMap m;
    m["emoji"] = emoji;
    m["count"] = count;
    if (!colors.isEmpty())
        m["colors"] = QVariant::fromValue(colors);
    return m;
}

static void setMsg(QStandardItem *item,
                   const QString &author, const QString &text, const QString &time,
                   const QPixmap &avatar, bool edited,
                   bool hasQuote, const QString &qAuthor, const QString &qText,
                   const QVariantList &reactions) {
    item->setData(author,  MsgAuthorRole);
    item->setData(text,    MsgTextRole);
    item->setData(time,    MsgTimeRole);
    item->setData(edited,  MsgEditedRole);
    item->setData(QVariant::fromValue(avatar), MsgAvatarRole);
    item->setData(hasQuote, MsgHasQuoteRole);
    if (hasQuote) {
        item->setData(qAuthor, MsgQuoteAuthorRole);
        item->setData(qText,   MsgQuoteTextRole);
    }
    if (!reactions.isEmpty())
        item->setData(reactions, MsgReactionsRole);
}

MessageList::MessageList(DbManager* db, QWidget *parent)
    : QWidget(parent)
    , m_view(new ChatView(this))
    , m_model(new QStandardItemModel(this))
    , m_inputBar(nullptr)
    , m_emojiPanel(nullptr)
    , m_db(db)
{
    auto *layout = new QVBoxLayout(this);
    layout->setContentsMargins(0, 0, 0, 0);
    layout->setSpacing(0);

    m_view->setModel(m_model);
    m_view->setItemDelegate(new MessageDelegate(this));
    m_view->setEditTriggers(QAbstractItemView::NoEditTriggers);
    m_view->setSelectionMode(QAbstractItemView::NoSelection);
    m_view->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    m_view->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
    m_view->setFrameShape(QFrame::NoFrame);
    m_view->setBackgroundImage("../resources/bg.jpg");
    layout->addWidget(m_view, 1);

    static std::vector<std::unique_ptr<LottieIcon>> s_icons;
    if (s_icons.empty()) {
        for (const auto &cat : builtinEmojiSet()) {
            for (const auto &e : cat.items) {
                if (e.type == EmojiType::Animation && !e.animPath.isEmpty()) {
                    QFile f(e.animPath);
                    if (f.open(QIODevice::ReadOnly)) {
                        auto icon = std::make_unique<LottieIcon>(f.readAll());
                        if (icon->isValid()) {
                            AnimTimer::instance()->registerIcon(e.animPath, icon.get());
                            s_icons.push_back(std::move(icon));
                        }
                    }
                }
            }
        }
    }

    m_emojiPanel = new EmojiPanel(this);
    layout->addWidget(m_emojiPanel);

    m_inputBar = new InputBar(m_emojiPanel, this);
    layout->addWidget(m_inputBar);

    connect(m_inputBar, &InputBar::sendMessage, this, [this](const QString &text) {
        auto av = makeAvatar(QColor(74, 144, 226), "Y");
        auto *item = new QStandardItem();
        auto ts = QDateTime::currentMSecsSinceEpoch();
        setMsg(item,
            QString::fromUtf8("You"), text,
            QDateTime::currentDateTime().toString("HH:mm"),
            av, false, false, QString(), QString(),
            QVariantList{});
        m_model->appendRow(item);
        m_view->scrollToBottom();

        if (m_db && !m_currentChannelId.isEmpty())
            m_db->insertMessage(m_currentChannelId, m_db->myNodeId(), text, ts, 1);

        if (m_propagator && !m_currentChannelId.isEmpty()) {
            static const unsigned char zeroSig[64] = {};
            m_propagator->propagateNewMessage(m_currentChannelId, text.toUtf8(), ts,
                                              QByteArray(reinterpret_cast<const char*>(zeroSig), 64));
        }
    });

    connect(AnimTimer::instance(), &AnimTimer::ticked, this, [this]() {
        m_view->viewport()->update();
    });

    connect(m_view, &ChatView::hoveredIndexChanged, this, [this](const QModelIndex &idx) {
        bool hasAnim = false;
        if (idx.isValid()) {
            QString text = idx.data(MsgTextRole).toString();
            for (auto it = g_animatedEmojiMap.begin(); it != g_animatedEmojiMap.end(); ++it) {
                if (text.contains(it.key())) { hasAnim = true; break; }
            }
            if (!hasAnim) {
                QVariantList reactions = idx.data(MsgReactionsRole).toList();
                for (const QVariant &rv : reactions) {
                    if (g_animatedEmojiMap.contains(rv.toMap()["emoji"].toString()))
                        { hasAnim = true; break; }
                }
            }
        }
        bool wasActive = m_animHoverActive;
        m_animHoverActive = hasAnim;
        if (!wasActive && m_animHoverActive) AnimTimer::instance()->activate();
        else if (wasActive && !m_animHoverActive) AnimTimer::instance()->deactivate();
    });
}

void MessageList::loadChannel(const QString& channelId) {
    m_model->clear();
    m_avatarCache.clear();
    m_currentChannelId = channelId;
    if (!m_db || !m_db->isOpen()) return;

    auto msgs = m_db->getMessages(channelId, 100);

    struct ReactionKey { qint64 msgId; quint64 node; QString emoji; };
    QHash<qint64, QHash<QString, QList<QColor>>> reactMap;

    for (const auto& m : msgs) {
        AccountRow acc = m_db->getAccount(m.authorNodeId);
        QString author  = acc.displayName.isEmpty()
                          ? QString("node_%1").arg(m.authorNodeId) : acc.displayName;
        QString letter  = acc.avatarLetter.isEmpty() ? author.mid(0, 1) : acc.avatarLetter;
        QColor  color(acc.avatarColor);

        if (!m_avatarCache.contains(m.authorNodeId)) {
            m_avatarCache[m.authorNodeId] = color;
        }

        auto avatar = makeAvatar(color, letter);
        auto time   = QDateTime::fromMSecsSinceEpoch(m.timestamp).toString("HH:mm");

        QVariantList reacts;
        auto *item = new QStandardItem();
        setMsg(item, author, m.content, time, avatar, false,
               false, QString(), QString(), reacts);
        m_model->appendRow(item);
    }

    if (m_model->rowCount() > 0)
        m_view->scrollToBottom();
    m_inputBar->setFocus();
}

void MessageList::addMessage(const QString& channelId, quint64 authorNodeId,
                              const QByteArray& content, qint64 timestamp) {
    if (channelId != m_currentChannelId) return;

    AccountRow acc = m_db ? m_db->getAccount(authorNodeId) : AccountRow();
    QString author = acc.displayName.isEmpty()
                     ? QString("node_%1").arg(authorNodeId) : acc.displayName;
    QString letter = acc.avatarLetter.isEmpty() ? author.mid(0, 1) : acc.avatarLetter;
    QColor  color(acc.avatarColor);
    auto avatar = makeAvatar(color, letter);
    auto time   = QDateTime::fromMSecsSinceEpoch(timestamp).toString("HH:mm");

    /* dedup */
    for (int r = 0; r < m_model->rowCount(); r++) {
        auto* it = m_model->item(r);
        if (it->data(MsgTimeRole).toString() == time
            && it->data(MsgAuthorRole).toString() == author) return;
    }

    auto *item = new QStandardItem();
    setMsg(item, author, QString::fromUtf8(content), time, avatar, false,
           false, QString(), QString(), QVariantList{});
    m_model->appendRow(item);

    if (m_model->rowCount() > 50)
        m_model->removeRow(0);

    m_view->scrollToBottom();
}