#include "patterneditormodel.h"
using Xybrid::UI::PatternEditorModel;
using Xybrid::UI::PatternEditorHeaderProxyModel;
using Xybrid::Data::Pattern;
#include "ui/patterneditorview.h"
using Xybrid::UI::PatternEditorView;

#include "util/strings.h"

#include <QDebug>
#include <QString>
#include <QFontMetrics>
#include <QTimer>
#include <QScrollBar>

namespace { // helper functions
    int cellWidthBase = -1;
    int cellWidthParam;
    int cellWidthParamTab;
    int headerHeight;
    QSize hsz, hhsz;

    constexpr char hexmap[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                               '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
                              };

    constexpr char notemap[] = "C-C#D-D#E-F-F#G-G#A-A#B-";

    QString hexStr(unsigned char *data, int len) {
        QString s(len * 2, ' ');
        for (int i = 0; i < len; ++i) {
            s[2 * i]     = hexmap[(data[i] & 0xF0) >> 4];
            s[2 * i + 1] = hexmap[data[i] & 0x0F];
        }
        return s;
    }
    QString byteStr(int t) {
        unsigned char c = static_cast<unsigned char>(t & 255);
        return hexStr(&c, 1);
    }

    QString noteStr(int n) {
        QString s(3, ' ');
        int nn = n % 12;
        int oc = (n - nn) / 12;
        s[2] = '0' + static_cast<char>(oc);
        s[0] = notemap[nn*2];
        s[1] = notemap[nn*2+1];
        return s;
    }
}

PatternEditorHeaderProxyModel::PatternEditorHeaderProxyModel(QObject *parent, PatternEditorModel* p) : QAbstractTableModel(parent), pm(p) { }
int PatternEditorHeaderProxyModel::rowCount(const QModelIndex&) const {
    return 1;
}
int PatternEditorHeaderProxyModel::columnCount(const QModelIndex&) const {
    return pm->hdrColumnCount();
}
QVariant PatternEditorHeaderProxyModel::data(const QModelIndex&, int) const {
    return QVariant();
}
QVariant PatternEditorHeaderProxyModel::headerData(int section, Qt::Orientation orientation, int role) const {
    return pm->hdrData(section, orientation, role);
}

PatternEditorModel::PatternEditorModel(QObject *parent)
    :QAbstractTableModel(parent) {
    hprox = new PatternEditorHeaderProxyModel(parent, this);

    auto view = static_cast<PatternEditorView*>(parent);
    int rowHeight = [] {
        QFontMetrics fm = QFontMetrics(QFont());
        return (fm.boundingRect("255").size() + QSize(8, 4)).height();
    }();
    endHeight = (view->viewport()->height() - rowHeight) / 2;
    connect(view->verticalScrollBar(), &QScrollBar::rangeChanged, this, [this, view, rowHeight] {
        endHeight = (view->viewport()->height() - rowHeight) / 2;
        emit this->layoutChanged();
    });
}

int PatternEditorModel::rowCount(const QModelIndex & /*parent*/) const {
    //if (pattern->channels.size() == 0) return 1;
    return pattern->rows + 2;
}

int PatternEditorModel::columnCount(const QModelIndex & /*parent*/) const {
    if (pattern->channels.size() == 0) return 1;
    return colsPerChannel * static_cast<int>(pattern->channels.size()) + 1;
}

QVariant PatternEditorModel::data(const QModelIndex &index, int role) const {
    if (role == Qt::DisplayRole) {
        if (index.row() == 0) return QVariant();
        if (index.row() > pattern->rows || index.column() >= colsPerChannel * static_cast<int>(pattern->channels.size())) return QVariant();
        int cc = index.column() % colsPerChannel;
        int ch = (index.column() - cc) / colsPerChannel;
        auto& row = pattern->rowAt(ch, index.row()-1);
        if (cc == 0) { // port
            if (row.port >= 0 && row.port < 256) return byteStr(row.port);
            if (row.port == -2) return qs("(G)");
            if (row.port == -3) return qs("L");
            return qs(" - ");
        } else if (cc == 1) { // note
            if (row.note >= 0) return noteStr(row.note);
            if (row.note == -2) return qs(" ^ "); // note off
            if (row.note == -3) return qs(" x "); // hard cut
            return qs(" - ");
        } else {
            size_t cp = static_cast<size_t>(((cc - 2) - (cc % 2)) / 2);
            if (cc % 2 == 0) {
                if (row.numParams() > cp) return QString(1,static_cast<char>(row.params->at(cp)[0]));
                if (row.numParams() == cp) return qs("» ");
                return qs("");
            }
            if (row.numParams() > cp) {
                if (row.params->at(cp)[0] == ' ') return qs("- ");
                return byteStr(row.params->at(cp)[1]);
            }
            return qs("");
        }
    } else if (role == Qt::SizeHintRole) {
        if (index.row() >= pattern->rows) return QSize(-1, -1);
    }
    return QVariant();
}

QVariant PatternEditorModel::headerData(int section, Qt::Orientation orientation, int role) const {
    if (role == Qt::DisplayRole) {
        if (orientation == Qt::Orientation::Horizontal) return QVariant(); // blank actual-header
        if (section == 0 || section > pattern->rows) return QVariant(); // blank end section
        return QString::number(section-1);
    } else if (role == Qt::SizeHintRole) {
        if (orientation == Qt::Orientation::Vertical) if (section == 0 || section > pattern->rows) return QSize(-1, endHeight); // fill ends to center
        if (hsz.isEmpty()) {
            auto fm = QFontMetrics(QFont(/*"Iosevka Term Light", 9*/));
            hsz = fm.boundingRect("255").size() + QSize(8, 4); // this should fit 0-999
            hhsz = QSize(0, hsz.height());
        }
        return orientation == Qt::Vertical ? hsz : hhsz;

        //return QSize(0, fm.height() + 4);
    } else if (role == Qt::TextAlignmentRole) return Qt::AlignCenter;
    return QVariant();
}

Qt::ItemFlags PatternEditorModel::flags(const QModelIndex &index) const {
    if (index.row() == 0 || index.row() >= pattern->rows + 1 || (pattern->channels.size() > 0 && index.column() >= colsPerChannel * static_cast<int>(pattern->channels.size()))) {
        return QAbstractTableModel::flags(index) & ~(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
    }
    return QAbstractTableModel::flags(index);
}

int PatternEditorModel::hdrColumnCount() const {
    return static_cast<int>(pattern->channels.size()) + 1;
}
QVariant PatternEditorModel::hdrData(int section, Qt::Orientation, int role) const {
    if (role == Qt::DisplayRole || role == Qt::ToolTipRole) {
        if (pattern->channels.size() == 0) return QString("(no channels)");
        if (static_cast<size_t>(section) >= pattern->channels.size()) return QString("");
        auto n = pattern->channels.at(static_cast<size_t>(section)).name;
        //if (n.length() == 0) return QString("(Channel %1)").arg(section);
        if (n.length() == 0) return QString("(ch%1)").arg(section);
        return n;
    } else if (role == Qt::SizeHintRole) {
        if (cellWidthBase <= 0) {
            auto fm = QFontMetrics(QFont("Iosevka Term Light", 9));
            headerHeight = fm.height()+4;
            cellWidthBase = fm.horizontalAdvance(QString("FF")) + fm.horizontalAdvance(QString("C#2")) + cellPadding*4;
            cellWidthParamTab = fm.horizontalAdvance(QString("v")) + cellPadding;
            cellWidthParam = cellWidthParamTab + fm.horizontalAdvance(QString("FF")) + cellPadding;
        }
        return QSize(0, headerHeight);
    }
    return QVariant();
}

void PatternEditorModel::setPattern(const std::shared_ptr<Pattern>& pattern) {
    if (this->pattern == pattern) return;
    this->pattern = pattern;
    refresh();
}

void PatternEditorModel::updateColumnDisplay() {
    if (pattern == nullptr) return;
    auto view = static_cast<PatternEditorView*>(parent());
    //view->setUpdatesEnabled(false);
    //auto fm = QFontMetrics(QFont("Iosevka Term Light", 9));
    for (size_t ch = 0; ch < pattern->channels.size(); ch++) {
        auto& c = pattern->channels.at(ch);
        size_t maxParams = 0;
        for (auto& r : c.rows) {
            if (r.numParams() > maxParams) maxParams = r.numParams();
        }
        int lastShown = 0;
        int chWidth = 0;
        for (size_t i = 0; i < PatternEditorModel::colsPerChannel; i++) {
            auto col = static_cast<int>(ch*PatternEditorModel::colsPerChannel+i);
            view->setColumnHidden(col, false); // always unhide to ensure hiding actually prevents columns from being selected
            if (i < 3+2*maxParams) {
                view->resizeColumnToContents(col);
                lastShown = col;
                chWidth += view->columnWidth(col);
            } else view->setColumnHidden(col, true);
            //view->setColumnWidth(col, 1);
        }
        int minWidth = 0;
        if (fitHeaderToName) { // ensure exact fit
            QStyleOptionHeader opt;
            opt.initFrom(view->horizontalHeader());
            opt.state = QStyle::State_None | QStyle::State_Raised | QStyle::State_Horizontal;
            opt.orientation = Qt::Horizontal;
            opt.section = 0;
            opt.fontMetrics = view->horizontalHeader()->fontMetrics();
            opt.text = c.name;
            minWidth = view->horizontalHeader()->style()->sizeFromContents(QStyle::CT_HeaderSection, &opt, QSize(), view->horizontalHeader()).width();
        }
        int lsw = view->columnWidth(lastShown);
        view->setColumnWidth(lastShown, std::max(lsw + 3, minWidth - (chWidth - lsw)));
    }
    //view->setUpdatesEnabled(true);
    view->updateHeader(true);
}

void PatternEditorModel::updateFold() {
    auto view = static_cast<PatternEditorView*>(parent());
    //view->setUpdatesEnabled(false);
    int ifold = 1;
    if (folded && pattern->fold > 1) ifold = pattern->fold;
    int rows = this->rowCount()-2;
    view->setRowHidden(0, false);
    view->setRowHidden(rows+1, false);
    for (int i = 0; i < rows; i++) {
        view->setRowHidden(i+1, false); // dispel any "phantoms" we might end up having
        if (i < pattern->rows && i % ifold != 0) view->setRowHidden(i+1, true);
    }
    //view->setUpdatesEnabled(true);
}

void PatternEditorModel::toggleFold() {
    folded = !folded;

    refresh();
}