git.sesse.net Git - nageru/blob - midi_mapping_dialog.cpp

   1 #include "midi_mapping_dialog.h"
   2
   3 #include <assert.h>
   4 #include <google/protobuf/descriptor.h>
   5 #include <google/protobuf/message.h>
   6 #include <QComboBox>
   7 #include <QDialogButtonBox>
   8 #include <QFileDialog>
   9 #include <QMessageBox>
  10 #include <QPushButton>
  11 #include <QSpinBox>
  12 #include <QStringList>
  13 #include <QTreeWidget>
  14 #include <stdio.h>
  15 #include <algorithm>
  16 #include <cstddef>
  17 #include <functional>
  18 #include <limits>
  19 #include <string>
  20
  21 #include "midi_mapper.h"
  22 #include "midi_mapping.pb.h"
  23 #include "post_to_main_thread.h"
  24 #include "ui_midi_mapping.h"
  25
  26 class QObject;
  27
  28 using namespace google::protobuf;
  29 using namespace std;
  30
  31 vector<MIDIMappingDialog::Control> per_bus_controllers = {
  32         { "Treble",                   MIDIMappingBusProto::kTrebleFieldNumber, MIDIMappingProto::kTrebleBankFieldNumber },
  33         { "Mid",                      MIDIMappingBusProto::kMidFieldNumber,    MIDIMappingProto::kMidBankFieldNumber },
  34         { "Bass",                     MIDIMappingBusProto::kBassFieldNumber,   MIDIMappingProto::kBassBankFieldNumber },
  35         { "Gain",                     MIDIMappingBusProto::kGainFieldNumber,   MIDIMappingProto::kGainBankFieldNumber },
  36         { "Compressor threshold",     MIDIMappingBusProto::kCompressorThresholdFieldNumber,
  37                                       MIDIMappingProto::kCompressorThresholdBankFieldNumber},
  38         { "Fader",                    MIDIMappingBusProto::kFaderFieldNumber,  MIDIMappingProto::kFaderBankFieldNumber }
  39 };
  40 vector<MIDIMappingDialog::Control> per_bus_buttons = {
  41         { "Toggle mute",              MIDIMappingBusProto::kToggleMuteFieldNumber,
  42                                       MIDIMappingProto::kToggleMuteBankFieldNumber },
  43         { "Toggle locut",             MIDIMappingBusProto::kToggleLocutFieldNumber,
  44                                       MIDIMappingProto::kToggleLocutBankFieldNumber },
  45         { "Togle auto gain staging",  MIDIMappingBusProto::kToggleAutoGainStagingFieldNumber,
  46                                       MIDIMappingProto::kToggleAutoGainStagingBankFieldNumber },
  47         { "Togle compressor",         MIDIMappingBusProto::kToggleCompressorFieldNumber,
  48                                       MIDIMappingProto::kToggleCompressorBankFieldNumber },
  49         { "Clear peak",               MIDIMappingBusProto::kClearPeakFieldNumber,
  50                                       MIDIMappingProto::kClearPeakBankFieldNumber }
  51 };
  52 vector<MIDIMappingDialog::Control> per_bus_lights = {
  53         { "Is muted",                 MIDIMappingBusProto::kIsMutedFieldNumber, 0 },
  54         { "Locut is on",              MIDIMappingBusProto::kLocutIsOnFieldNumber, 0 },
  55         { "Auto gain staging is on",  MIDIMappingBusProto::kAutoGainStagingIsOnFieldNumber, 0 },
  56         { "Compressor is on",         MIDIMappingBusProto::kCompressorIsOnFieldNumber, 0 },
  57         { "Bus has peaked",           MIDIMappingBusProto::kHasPeakedFieldNumber, 0 }
  58 };
  59 vector<MIDIMappingDialog::Control> global_controllers = {
  60         { "Locut cutoff",             MIDIMappingBusProto::kLocutFieldNumber,  MIDIMappingProto::kLocutBankFieldNumber },
  61         { "Limiter threshold",        MIDIMappingBusProto::kLimiterThresholdFieldNumber,
  62                                       MIDIMappingProto::kLimiterThresholdBankFieldNumber },
  63         { "Makeup gain",              MIDIMappingBusProto::kMakeupGainFieldNumber,
  64                                       MIDIMappingProto::kMakeupGainBankFieldNumber }
  65 };
  66 vector<MIDIMappingDialog::Control> global_buttons = {
  67         { "Previous bank",            MIDIMappingBusProto::kPrevBankFieldNumber, 0 },
  68         { "Next bank",                MIDIMappingBusProto::kNextBankFieldNumber, 0 },
  69         { "Select bank 1",            MIDIMappingBusProto::kSelectBank1FieldNumber, 0 },
  70         { "Select bank 2",            MIDIMappingBusProto::kSelectBank2FieldNumber, 0 },
  71         { "Select bank 3",            MIDIMappingBusProto::kSelectBank3FieldNumber, 0 },
  72         { "Select bank 4",            MIDIMappingBusProto::kSelectBank4FieldNumber, 0 },
  73         { "Select bank 5",            MIDIMappingBusProto::kSelectBank5FieldNumber, 0 },
  74         { "Toggle limiter",           MIDIMappingBusProto::kToggleLimiterFieldNumber, MIDIMappingProto::kToggleLimiterBankFieldNumber },
  75         { "Toggle auto makeup gain",  MIDIMappingBusProto::kToggleAutoMakeupGainFieldNumber, MIDIMappingProto::kToggleAutoMakeupGainBankFieldNumber }
  76 };
  77 vector<MIDIMappingDialog::Control> global_lights = {
  78         { "Bank 1 is selected",       MIDIMappingBusProto::kBank1IsSelectedFieldNumber, 0 },
  79         { "Bank 2 is selected",       MIDIMappingBusProto::kBank2IsSelectedFieldNumber, 0 },
  80         { "Bank 3 is selected",       MIDIMappingBusProto::kBank3IsSelectedFieldNumber, 0 },
  81         { "Bank 4 is selected",       MIDIMappingBusProto::kBank4IsSelectedFieldNumber, 0 },
  82         { "Bank 5 is selected",       MIDIMappingBusProto::kBank5IsSelectedFieldNumber, 0 },
  83         { "Limiter is on",            MIDIMappingBusProto::kLimiterIsOnFieldNumber, 0 },
  84         { "Auto makeup gain is on",   MIDIMappingBusProto::kAutoMakeupGainIsOnFieldNumber, 0 },
  85 };
  86
  87 namespace {
  88
  89 int get_bank(const MIDIMappingProto &mapping_proto, int bank_field_number, int default_value)
  90 {
  91         const FieldDescriptor *bank_descriptor = mapping_proto.GetDescriptor()->FindFieldByNumber(bank_field_number);
  92         const Reflection *reflection = mapping_proto.GetReflection();
  93         if (!reflection->HasField(mapping_proto, bank_descriptor)) {
  94                 return default_value;
  95         }
  96         return reflection->GetInt32(mapping_proto, bank_descriptor);
  97 }
  98
  99 int get_controller_mapping(const MIDIMappingProto &mapping_proto, size_t bus_idx, int field_number, int default_value)
 100 {
 101         if (bus_idx >= size_t(mapping_proto.bus_mapping_size())) {
 102                 return default_value;
 103         }
 104
 105         const MIDIMappingBusProto &bus_mapping = mapping_proto.bus_mapping(bus_idx);
 106         const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
 107         const Reflection *bus_reflection = bus_mapping.GetReflection();
 108         if (!bus_reflection->HasField(bus_mapping, descriptor)) {
 109                 return default_value;
 110         }
 111         const MIDIControllerProto &controller_proto =
 112                 static_cast<const MIDIControllerProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
 113         return controller_proto.controller_number();
 114 }
 115
 116 int get_button_mapping(const MIDIMappingProto &mapping_proto, size_t bus_idx, int field_number, int default_value)
 117 {
 118         if (bus_idx >= size_t(mapping_proto.bus_mapping_size())) {
 119                 return default_value;
 120         }
 121
 122         const MIDIMappingBusProto &bus_mapping = mapping_proto.bus_mapping(bus_idx);
 123         const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
 124         const Reflection *bus_reflection = bus_mapping.GetReflection();
 125         if (!bus_reflection->HasField(bus_mapping, descriptor)) {
 126                 return default_value;
 127         }
 128         const MIDIButtonProto &bus_proto =
 129                 static_cast<const MIDIButtonProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
 130         return bus_proto.note_number();
 131 }
 132
 133 int get_light_mapping(const MIDIMappingProto &mapping_proto, size_t bus_idx, int field_number, int default_value)
 134 {
 135         if (bus_idx >= size_t(mapping_proto.bus_mapping_size())) {
 136                 return default_value;
 137         }
 138
 139         const MIDIMappingBusProto &bus_mapping = mapping_proto.bus_mapping(bus_idx);
 140         const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
 141         const Reflection *bus_reflection = bus_mapping.GetReflection();
 142         if (!bus_reflection->HasField(bus_mapping, descriptor)) {
 143                 return default_value;
 144         }
 145         const MIDILightProto &bus_proto =
 146                 static_cast<const MIDILightProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
 147         return bus_proto.note_number();
 148 }
 149
 150 }  // namespace
 151
 152 MIDIMappingDialog::MIDIMappingDialog(MIDIMapper *mapper)
 153         : ui(new Ui::MIDIMappingDialog),
 154           mapper(mapper)
 155 {
 156         ui->setupUi(this);
 157
 158         const MIDIMappingProto mapping_proto = mapper->get_current_mapping();  // Take a copy.
 159         old_receiver = mapper->set_receiver(this);
 160
 161         QStringList labels;
 162         labels << "";
 163         labels << "Controller bank";
 164         for (unsigned bus_idx = 0; bus_idx < num_buses; ++bus_idx) {
 165                 char buf[256];
 166                 snprintf(buf, sizeof(buf), "Bus %d", bus_idx + 1);
 167                 labels << buf;
 168         }
 169         labels << "";
 170         ui->treeWidget->setColumnCount(num_buses + 3);
 171         ui->treeWidget->setHeaderLabels(labels);
 172
 173         add_controls("Per-bus controllers", ControlType::CONTROLLER, SpinnerGroup::PER_BUS_CONTROLLERS, mapping_proto, per_bus_controllers);
 174         add_controls("Per-bus buttons", ControlType::BUTTON, SpinnerGroup::PER_BUS_BUTTONS, mapping_proto, per_bus_buttons);
 175         add_controls("Per-bus lights", ControlType::LIGHT, SpinnerGroup::PER_BUS_LIGHTS, mapping_proto, per_bus_lights);
 176         add_controls("Global controllers", ControlType::CONTROLLER, SpinnerGroup::GLOBAL_CONTROLLERS, mapping_proto, global_controllers);
 177         add_controls("Global buttons", ControlType::BUTTON, SpinnerGroup::GLOBAL_BUTTONS, mapping_proto, global_buttons);
 178         add_controls("Global lights", ControlType::LIGHT, SpinnerGroup::GLOBAL_LIGHTS, mapping_proto, global_lights);
 179         fill_controls_from_mapping(mapping_proto);
 180
 181         // Auto-resize every column but the last.
 182         for (unsigned column_idx = 0; column_idx < num_buses + 3; ++column_idx) {
 183                 ui->treeWidget->resizeColumnToContents(column_idx);
 184         }
 185
 186         connect(ui->guess_bus_button, &QPushButton::clicked,
 187                 bind(&MIDIMappingDialog::guess_clicked, this, false));
 188         connect(ui->guess_group_button, &QPushButton::clicked,
 189                 bind(&MIDIMappingDialog::guess_clicked, this, true));
 190         connect(ui->ok_cancel_buttons, &QDialogButtonBox::accepted, this, &MIDIMappingDialog::ok_clicked);
 191         connect(ui->ok_cancel_buttons, &QDialogButtonBox::rejected, this, &MIDIMappingDialog::cancel_clicked);
 192         connect(ui->save_button, &QPushButton::clicked, this, &MIDIMappingDialog::save_clicked);
 193         connect(ui->load_button, &QPushButton::clicked, this, &MIDIMappingDialog::load_clicked);
 194
 195         update_guess_button_state();
 196 }
 197
 198 MIDIMappingDialog::~MIDIMappingDialog()
 199 {
 200         mapper->set_receiver(old_receiver);
 201         mapper->refresh_highlights();
 202 }
 203
 204 bool MIDIMappingDialog::eventFilter(QObject *obj, QEvent *event)
 205 {
 206         if (event->type() == QEvent::FocusIn ||
 207             event->type() == QEvent::FocusOut) {
 208                 // We ignore the guess buttons themselves; it should be allowed
 209                 // to navigate from a spinner to focus on a button (to click it).
 210                 if (obj != ui->guess_bus_button && obj != ui->guess_group_button) {
 211                         update_guess_button_state();
 212                 }
 213         }
 214         return false;
 215 }
 216
 217 void MIDIMappingDialog::guess_clicked(bool limit_to_group)
 218 {
 219         FocusInfo focus = find_focus();
 220         if (focus.bus_idx == -1) {
 221                 // The guess button probably took the focus away from us.
 222                 focus = last_focus;
 223         }
 224         assert(focus.bus_idx != -1);  // The button should have been disabled.
 225         pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, limit_to_group ? focus.spinner_group : SpinnerGroup::ALL_GROUPS);
 226         const int source_bus_idx = bus_and_offset.first;
 227         const int offset = bus_and_offset.second;
 228         assert(source_bus_idx != -1);  // The button should have been disabled.
 229
 230         for (const auto &field_number_and_spinner : spinners[focus.bus_idx]) {
 231                 int field_number = field_number_and_spinner.first;
 232                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 233                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 234
 235                 if (limit_to_group && this_spinner_group != focus.spinner_group) {
 236                         continue;
 237                 }
 238
 239                 assert(spinners[source_bus_idx].count(field_number));
 240                 QSpinBox *source_spinner = spinners[source_bus_idx][field_number].spinner;
 241                 assert(spinners[source_bus_idx][field_number].group == this_spinner_group);
 242
 243                 if (source_spinner->value() != -1) {
 244                         spinner->setValue(source_spinner->value() + offset);
 245                 }
 246         }
 247
 248         // See if we can find a “next” bus to move the focus to.
 249         const int next_bus_idx = focus.bus_idx + (focus.bus_idx - source_bus_idx);  // Note: Could become e.g. -1.
 250         for (const InstantiatedSpinner &is : controller_spinners) {
 251                 if (int(is.bus_idx) == next_bus_idx && is.field_number == focus.field_number) {
 252                         is.spinner->setFocus();
 253                 }
 254         }
 255         for (const InstantiatedSpinner &is : button_spinners) {
 256                 if (int(is.bus_idx) == next_bus_idx && is.field_number == focus.field_number) {
 257                         is.spinner->setFocus();
 258                 }
 259         }
 260         for (const InstantiatedSpinner &is : light_spinners) {
 261                 if (int(is.bus_idx) == next_bus_idx && is.field_number == focus.field_number) {
 262                         is.spinner->setFocus();
 263                 }
 264         }
 265 }
 266
 267 void MIDIMappingDialog::ok_clicked()
 268 {
 269         unique_ptr<MIDIMappingProto> new_mapping = construct_mapping_proto_from_ui();
 270         mapper->set_midi_mapping(*new_mapping);
 271         mapper->set_receiver(old_receiver);
 272         accept();
 273 }
 274
 275 void MIDIMappingDialog::cancel_clicked()
 276 {
 277         mapper->set_receiver(old_receiver);
 278         reject();
 279 }
 280
 281 void MIDIMappingDialog::save_clicked()
 282 {
 283 #if HAVE_CEF
 284         // The native file dialog uses GTK+, which interferes with CEF's use of the GLib main loop.
 285         QFileDialog::Option options(QFileDialog::DontUseNativeDialog);
 286 #else
 287         QFileDialog::Option options;
 288 #endif
 289         unique_ptr<MIDIMappingProto> new_mapping = construct_mapping_proto_from_ui();
 290         QString filename = QFileDialog::getSaveFileName(this,
 291                 "Save MIDI mapping", QString(), tr("Mapping files (*.midimapping)"), /*selectedFilter=*/nullptr, options);
 292         if (!filename.endsWith(".midimapping")) {
 293                 filename += ".midimapping";
 294         }
 295         if (!save_midi_mapping_to_file(*new_mapping, filename.toStdString())) {
 296                 QMessageBox box;
 297                 box.setText("Could not save mapping to '" + filename + "'. Check that you have the right permissions and try again.");
 298                 box.exec();
 299         }
 300 }
 301
 302 void MIDIMappingDialog::load_clicked()
 303 {
 304 #if HAVE_CEF
 305         // The native file dialog uses GTK+, which interferes with CEF's use of the GLib main loop.
 306         QFileDialog::Option options(QFileDialog::DontUseNativeDialog);
 307 #else
 308         QFileDialog::Option options;
 309 #endif
 310         QString filename = QFileDialog::getOpenFileName(this,
 311                 "Load MIDI mapping", QString(), tr("Mapping files (*.midimapping)"), /*selectedFilter=*/nullptr, options);
 312         MIDIMappingProto new_mapping;
 313         if (!load_midi_mapping_from_file(filename.toStdString(), &new_mapping)) {
 314                 QMessageBox box;
 315                 box.setText("Could not load mapping from '" + filename + "'. Check that the file exists, has the right permissions and is valid.");
 316                 box.exec();
 317                 return;
 318         }
 319
 320         fill_controls_from_mapping(new_mapping);
 321 }
 322
 323 namespace {
 324
 325 template<class T>
 326 T *get_mutable_bus_message(MIDIMappingProto *mapping_proto, unsigned bus_idx, int field_number)
 327 {
 328         while (size_t(mapping_proto->bus_mapping_size()) <= bus_idx) {
 329                 mapping_proto->add_bus_mapping();
 330         }
 331
 332         MIDIMappingBusProto *bus_mapping = mapping_proto->mutable_bus_mapping(bus_idx);
 333         const FieldDescriptor *descriptor = bus_mapping->GetDescriptor()->FindFieldByNumber(field_number);
 334         const Reflection *bus_reflection = bus_mapping->GetReflection();
 335         return static_cast<T *>(bus_reflection->MutableMessage(bus_mapping, descriptor));
 336 }
 337
 338 }  // namespace
 339
 340 unique_ptr<MIDIMappingProto> MIDIMappingDialog::construct_mapping_proto_from_ui()
 341 {
 342         unique_ptr<MIDIMappingProto> mapping_proto(new MIDIMappingProto);
 343         for (const InstantiatedSpinner &is : controller_spinners) {
 344                 const int val = is.spinner->value();
 345                 if (val == -1) {
 346                         continue;
 347                 }
 348
 349                 MIDIControllerProto *controller_proto =
 350                         get_mutable_bus_message<MIDIControllerProto>(mapping_proto.get(), is.bus_idx, is.field_number);
 351                 controller_proto->set_controller_number(val);
 352         }
 353         for (const InstantiatedSpinner &is : button_spinners) {
 354                 const int val = is.spinner->value();
 355                 if (val == -1) {
 356                         continue;
 357                 }
 358
 359                 MIDIButtonProto *button_proto =
 360                         get_mutable_bus_message<MIDIButtonProto>(mapping_proto.get(), is.bus_idx, is.field_number);
 361                 button_proto->set_note_number(val);
 362         }
 363         for (const InstantiatedSpinner &is : light_spinners) {
 364                 const int val = is.spinner->value();
 365                 if (val == -1) {
 366                         continue;
 367                 }
 368
 369                 MIDILightProto *light_proto =
 370                         get_mutable_bus_message<MIDILightProto>(mapping_proto.get(), is.bus_idx, is.field_number);
 371                 light_proto->set_note_number(val);
 372         }
 373         int highest_bank_used = 0;  // 1-indexed.
 374         for (const InstantiatedComboBox &ic : bank_combo_boxes) {
 375                 const int val = ic.combo_box->currentIndex();
 376                 highest_bank_used = std::max(highest_bank_used, val);
 377                 if (val == 0) {
 378                         continue;
 379                 }
 380
 381                 const FieldDescriptor *descriptor = mapping_proto->GetDescriptor()->FindFieldByNumber(ic.field_number);
 382                 const Reflection *bus_reflection = mapping_proto->GetReflection();
 383                 bus_reflection->SetInt32(mapping_proto.get(), descriptor, val - 1);
 384         }
 385         mapping_proto->set_num_controller_banks(highest_bank_used);
 386         return mapping_proto;
 387 }
 388
 389 void MIDIMappingDialog::add_bank_selector(QTreeWidgetItem *item, const MIDIMappingProto &mapping_proto, int bank_field_number)
 390 {
 391         if (bank_field_number == 0) {
 392                 return;
 393         }
 394         QComboBox *bank_selector = new QComboBox(this);
 395         bank_selector->addItems(QStringList() << "" << "Bank 1" << "Bank 2" << "Bank 3" << "Bank 4" << "Bank 5");
 396         bank_selector->setAutoFillBackground(true);
 397
 398         bank_combo_boxes.push_back(InstantiatedComboBox{ bank_selector, bank_field_number });
 399
 400         ui->treeWidget->setItemWidget(item, 1, bank_selector);
 401 }
 402
 403 void MIDIMappingDialog::add_controls(const string &heading,
 404                                      MIDIMappingDialog::ControlType control_type,
 405                                      MIDIMappingDialog::SpinnerGroup spinner_group,
 406                                      const MIDIMappingProto &mapping_proto,
 407                                      const vector<MIDIMappingDialog::Control> &controls)
 408 {
 409         QTreeWidgetItem *heading_item = new QTreeWidgetItem(ui->treeWidget);
 410         heading_item->setText(0, QString::fromStdString(heading));
 411         heading_item->setFirstColumnSpanned(true);
 412         heading_item->setExpanded(true);
 413         for (const Control &control : controls) {
 414                 QTreeWidgetItem *item = new QTreeWidgetItem(heading_item);
 415                 heading_item->addChild(item);
 416                 add_bank_selector(item, mapping_proto, control.bank_field_number);
 417                 item->setText(0, QString::fromStdString(control.label + "   "));
 418
 419                 for (unsigned bus_idx = 0; bus_idx < num_buses; ++bus_idx) {
 420                         QSpinBox *spinner = new QSpinBox(this);
 421                         spinner->setRange(-1, 127);
 422                         spinner->setAutoFillBackground(true);
 423                         spinner->setSpecialValueText("\u200d");  // Zero-width joiner (ie., empty).
 424                         spinner->installEventFilter(this);  // So we know when the focus changes.
 425                         ui->treeWidget->setItemWidget(item, bus_idx + 2, spinner);
 426
 427                         if (control_type == ControlType::CONTROLLER) {
 428                                 controller_spinners.push_back(InstantiatedSpinner{ spinner, bus_idx, spinner_group, control.field_number });
 429                         } else if (control_type == ControlType::BUTTON) {
 430                                 button_spinners.push_back(InstantiatedSpinner{ spinner, bus_idx, spinner_group, control.field_number });
 431                         } else {
 432                                 assert(control_type == ControlType::LIGHT);
 433                                 light_spinners.push_back(InstantiatedSpinner{ spinner, bus_idx, spinner_group, control.field_number });
 434                         }
 435                         spinners[bus_idx][control.field_number] = SpinnerAndGroup{ spinner, spinner_group };
 436                         connect(spinner, static_cast<void(QSpinBox::*)(int)>(&QSpinBox::valueChanged),
 437                                 bind(&MIDIMappingDialog::update_guess_button_state, this));
 438                 }
 439         }
 440         ui->treeWidget->addTopLevelItem(heading_item);
 441 }
 442
 443 void MIDIMappingDialog::fill_controls_from_mapping(const MIDIMappingProto &mapping_proto)
 444 {
 445         for (const InstantiatedSpinner &is : controller_spinners) {
 446                 is.spinner->setValue(get_controller_mapping(mapping_proto, is.bus_idx, is.field_number, -1));
 447         }
 448         for (const InstantiatedSpinner &is : button_spinners) {
 449                 is.spinner->setValue(get_button_mapping(mapping_proto, is.bus_idx, is.field_number, -1));
 450         }
 451         for (const InstantiatedSpinner &is : light_spinners) {
 452                 is.spinner->setValue(get_light_mapping(mapping_proto, is.bus_idx, is.field_number, -1));
 453         }
 454         for (const InstantiatedComboBox &ic : bank_combo_boxes) {
 455                 ic.combo_box->setCurrentIndex(get_bank(mapping_proto, ic.field_number, -1) + 1);
 456         }
 457 }
 458
 459 void MIDIMappingDialog::controller_changed(unsigned controller)
 460 {
 461         post_to_main_thread([=]{
 462                 for (const InstantiatedSpinner &is : controller_spinners) {
 463                         if (is.spinner->hasFocus()) {
 464                                 is.spinner->setValue(controller);
 465                                 is.spinner->selectAll();
 466                         }
 467                 }
 468         });
 469 }
 470
 471 void MIDIMappingDialog::note_on(unsigned note)
 472 {
 473         post_to_main_thread([=]{
 474                 for (const InstantiatedSpinner &is : button_spinners) {
 475                         if (is.spinner->hasFocus()) {
 476                                 is.spinner->setValue(note);
 477                                 is.spinner->selectAll();
 478                         }
 479                 }
 480                 for (const InstantiatedSpinner &is : light_spinners) {
 481                         if (is.spinner->hasFocus()) {
 482                                 is.spinner->setValue(note);
 483                                 is.spinner->selectAll();
 484                         }
 485                 }
 486         });
 487 }
 488
 489 pair<int, int> MIDIMappingDialog::guess_offset(unsigned bus_idx, MIDIMappingDialog::SpinnerGroup spinner_group)
 490 {
 491         constexpr pair<int, int> not_found(-1, 0);
 492
 493         if (bus_is_empty(bus_idx, spinner_group)) {
 494                 return not_found;
 495         }
 496
 497         // See if we can find a non-empty bus to source from (prefer from the left).
 498         unsigned source_bus_idx;
 499         if (bus_idx > 0 && !bus_is_empty(bus_idx - 1, spinner_group)) {
 500                 source_bus_idx = bus_idx - 1;
 501         } else if (bus_idx < num_buses - 1 && !bus_is_empty(bus_idx + 1, spinner_group)) {
 502                 source_bus_idx = bus_idx + 1;
 503         } else {
 504                 return not_found;
 505         }
 506
 507         // See if we can find a consistent offset.
 508         bool found_offset = false;
 509         int offset = 0;
 510         int minimum_allowed_offset = numeric_limits<int>::min();
 511         int maximum_allowed_offset = numeric_limits<int>::max();
 512         for (const auto &field_number_and_spinner : spinners[bus_idx]) {
 513                 int field_number = field_number_and_spinner.first;
 514                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 515                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 516                 assert(spinners[source_bus_idx].count(field_number));
 517                 QSpinBox *source_spinner = spinners[source_bus_idx][field_number].spinner;
 518                 assert(spinners[source_bus_idx][field_number].group == this_spinner_group);
 519
 520                 if (spinner_group != SpinnerGroup::ALL_GROUPS &&
 521                     spinner_group != this_spinner_group) {
 522                         continue;
 523                 }
 524                 if (spinner->value() == -1) {
 525                         if (source_spinner->value() != -1) {
 526                                 // If the source value is e.g. 3, offset can't be less than -2 or larger than 124.
 527                                 // Otherwise, we'd extrapolate values outside [1..127].
 528                                 minimum_allowed_offset = max(minimum_allowed_offset, 1 - source_spinner->value());
 529                                 maximum_allowed_offset = min(maximum_allowed_offset, 127 - source_spinner->value());
 530                         }
 531                         continue;
 532                 }
 533                 if (source_spinner->value() == -1) {
 534                         // The bus has a controller set that the source bus doesn't set.
 535                         return not_found;
 536                 }
 537
 538                 int candidate_offset = spinner->value() - source_spinner->value();
 539                 if (!found_offset) {
 540                         offset = candidate_offset;
 541                         found_offset = true;
 542                 } else if (candidate_offset != offset) {
 543                         return not_found;
 544                 }
 545         }
 546
 547         if (!found_offset) {
 548                 // Given that the bus wasn't empty, this shouldn't happen.
 549                 assert(false);
 550                 return not_found;
 551         }
 552
 553         if (offset < minimum_allowed_offset || offset > maximum_allowed_offset) {
 554                 return not_found;
 555         }
 556         return make_pair(source_bus_idx, offset);
 557 }
 558
 559 bool MIDIMappingDialog::bus_is_empty(unsigned bus_idx, SpinnerGroup spinner_group)
 560 {
 561         for (const auto &field_number_and_spinner : spinners[bus_idx]) {
 562                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 563                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 564                 if (spinner_group != SpinnerGroup::ALL_GROUPS &&
 565                     spinner_group != this_spinner_group) {
 566                         continue;
 567                 }
 568                 if (spinner->value() != -1) {
 569                         return false;
 570                 }
 571         }
 572         return true;
 573 }
 574
 575 void MIDIMappingDialog::update_guess_button_state()
 576 {
 577         FocusInfo focus = find_focus();
 578         if (focus.bus_idx < 0) {
 579                 return;
 580         }
 581         {
 582                 pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, SpinnerGroup::ALL_GROUPS);
 583                 ui->guess_bus_button->setEnabled(bus_and_offset.first != -1);
 584         }
 585         {
 586                 pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, focus.spinner_group);
 587                 ui->guess_group_button->setEnabled(bus_and_offset.first != -1);
 588         }
 589         last_focus = focus;
 590 }
 591
 592 MIDIMappingDialog::FocusInfo MIDIMappingDialog::find_focus() const
 593 {
 594         for (const InstantiatedSpinner &is : controller_spinners) {
 595                 if (is.spinner->hasFocus()) {
 596                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 597                 }
 598         }
 599         for (const InstantiatedSpinner &is : button_spinners) {
 600                 if (is.spinner->hasFocus()) {
 601                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 602                 }
 603         }
 604         for (const InstantiatedSpinner &is : light_spinners) {
 605                 if (is.spinner->hasFocus()) {
 606                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 607                 }
 608         }
 609         return FocusInfo{ -1, SpinnerGroup::ALL_GROUPS, -1 };
 610 }