#include "dialogs/SchedulerDialog.hpp"

#include <QCheckBox>
#include <QComboBox>
#include <QDateEdit>
#include <QDialogButtonBox>
#include <QFormLayout>
#include <QHBoxLayout>
#include <QJsonArray>
#include <QLabel>
#include <QListWidget>
#include <QPointer>
#include <QPushButton>
#include <QSpinBox>
#include <QTimeEdit>
#include <QVBoxLayout>

#include "rpc/Protocol.hpp"
#include "rpc/RpcClient.hpp"
#include "util/Theme.hpp"

namespace velox::gui {
namespace {

// 0 = Sunday, matching Schedule.schema.json's daysOfWeek.
constexpr const char *kDayLabels[7] = {
    QT_TR_NOOP("Sun"), QT_TR_NOOP("Mon"), QT_TR_NOOP("Tue"), QT_TR_NOOP("Wed"),
    QT_TR_NOOP("Thu"), QT_TR_NOOP("Fri"), QT_TR_NOOP("Sat"),
};

}  // namespace

QJsonValue SchedulerDialog::buildSchedule(bool useSchedule, const QString &mode,
                                          const QString &startTime, bool runUntilDrains,
                                          const QString &stopTime, const QList<int> &daysOfWeek,
                                          const QString &onceDate) {
    if (!useSchedule) {
        return QJsonValue(QJsonValue::Null);
    }
    QJsonObject s{
        {"enabled", true},
        {"mode", mode},
        {"startTime", startTime},
        {"stopTime", runUntilDrains ? QJsonValue(QJsonValue::Null) : QJsonValue(stopTime)},
    };
    if (mode == QLatin1String("periodic")) {
        QJsonArray days;
        for (int d : daysOfWeek) {
            days.append(d);
        }
        s["daysOfWeek"] = days;
    } else {
        s["onceDate"] = onceDate;
    }
    return s;
}

SchedulerDialog::SchedulerDialog(rpc::RpcClient *client, QWidget *parent)
    : QDialog(parent),
      client_(client),
      queueList_(new QListWidget(this)),
      useSchedule_(new QCheckBox(tr("Run this queue on a schedule"), this)),
      mode_(new QComboBox(this)),
      startTime_(new QTimeEdit(this)),
      runUntilDrains_(new QCheckBox(tr("Run until the queue drains"), this)),
      stopTime_(new QTimeEdit(this)),
      onceDate_(new QDateEdit(this)),
      maxConcurrent_(new QSpinBox(this)),
      onComplete_(new QComboBox(this)),
      pauseRunningOnStop_(new QCheckBox(tr("Pause running tasks too"), this)),
      statusLabel_(new QLabel(this)) {
    setWindowTitle(tr("Scheduler"));
    resize(640, 420);

    queueList_->setMaximumWidth(200);

    mode_->addItem(tr("Once"), QStringLiteral("once"));
    mode_->addItem(tr("Periodic (weekly)"), QStringLiteral("periodic"));
    startTime_->setDisplayFormat(QStringLiteral("HH:mm"));
    stopTime_->setDisplayFormat(QStringLiteral("HH:mm"));
    onceDate_->setCalendarPopup(true);
    maxConcurrent_->setRange(1, 32);
    onComplete_->addItem(tr("Do nothing"), QStringLiteral("nothing"));
    onComplete_->addItem(tr("Exit Velox"), QStringLiteral("exit"));
    onComplete_->addItem(tr("Shut down"), QStringLiteral("shutdown"));
    onComplete_->addItem(tr("Hang up (disconnect network)"), QStringLiteral("hangup"));

    auto *daysRow = new QWidget(this);
    auto *daysLayout = new QHBoxLayout(daysRow);
    daysLayout->setContentsMargins(0, 0, 0, 0);
    for (int i = 0; i < 7; ++i) {
        dayChecks_[i] = new QCheckBox(tr(kDayLabels[i]), daysRow);
        daysLayout->addWidget(dayChecks_[i]);
    }

    auto *stopRow = new QWidget(this);
    auto *stopLayout = new QHBoxLayout(stopRow);
    stopLayout->setContentsMargins(0, 0, 0, 0);
    stopLayout->addWidget(stopTime_);
    stopLayout->addWidget(runUntilDrains_);
    connect(runUntilDrains_, &QCheckBox::toggled, stopTime_, &QWidget::setDisabled);

    const auto updateModeVisibility = [this, daysRow] {
        const bool periodic = mode_->currentData().toString() == QLatin1String("periodic");
        daysRow->setVisible(periodic);
        onceDate_->setVisible(!periodic);
    };
    connect(mode_, &QComboBox::currentIndexChanged, this, updateModeVisibility);
    updateModeVisibility();

    form_ = new QWidget(this);
    auto *form = new QFormLayout(form_);
    form->addRow(useSchedule_);
    form->addRow(tr("Mode:"), mode_);
    form->addRow(tr("Start time:"), startTime_);
    form->addRow(tr("Stop time:"), stopRow);
    form->addRow(tr("Days:"), daysRow);
    form->addRow(tr("Date:"), onceDate_);
    form->addRow(tr("Max concurrent:"), maxConcurrent_);
    form->addRow(tr("When the queue finishes:"), onComplete_);
    connect(useSchedule_, &QCheckBox::toggled, this, [this](bool on) {
        for (QWidget *w :
             {static_cast<QWidget *>(mode_), static_cast<QWidget *>(startTime_),
              static_cast<QWidget *>(stopTime_), static_cast<QWidget *>(runUntilDrains_),
              static_cast<QWidget *>(onceDate_)}) {
            w->setEnabled(on);
        }
    });

    statusLabel_->setStyleSheet(theme::errorLabelStyle());
    statusLabel_->hide();
    form_->setEnabled(false);  // no queue selected yet

    auto *startButton = new QPushButton(tr("Start Now"), this);
    auto *stopButton = new QPushButton(tr("Stop"), this);
    auto *saveButton = new QPushButton(tr("Save"), this);
    saveButton->setDefault(true);
    connect(startButton, &QPushButton::clicked, this, &SchedulerDialog::startNow);
    connect(stopButton, &QPushButton::clicked, this, &SchedulerDialog::stopNow);
    connect(saveButton, &QPushButton::clicked, this, &SchedulerDialog::save);

    auto *actionRow = new QHBoxLayout;
    actionRow->addWidget(startButton);
    actionRow->addWidget(stopButton);
    actionRow->addWidget(pauseRunningOnStop_);
    actionRow->addStretch();
    actionRow->addWidget(saveButton);

    auto *closeButtons = new QDialogButtonBox(QDialogButtonBox::Close, this);
    connect(closeButtons, &QDialogButtonBox::rejected, this, &QDialog::reject);
    connect(closeButtons, &QDialogButtonBox::accepted, this, &QDialog::accept);

    auto *rightLayout = new QVBoxLayout;
    rightLayout->addWidget(form_, 1);
    rightLayout->addWidget(statusLabel_);
    rightLayout->addLayout(actionRow);
    rightLayout->addWidget(closeButtons);

    auto *split = new QHBoxLayout(this);
    split->addWidget(queueList_);
    split->addLayout(rightLayout, 1);

    connect(queueList_, &QListWidget::currentItemChanged, this, &SchedulerDialog::onQueueSelected);

    QPointer<SchedulerDialog> self(this);
    client_->call(QString::fromLatin1(rpc::method::kQueueList), {},
                  [self](const rpc::RpcReply &reply) {
                      if (!self || !reply.ok()) {
                          return;
                      }
                      self->onQueuesLoaded(reply.result.toObject().value("items").toArray());
                  });
}

void SchedulerDialog::onQueuesLoaded(const QJsonArray &items) {
    queues_ = items;
    queueList_->clear();
    for (const QJsonValue &v : items) {
        auto *item = new QListWidgetItem(v.toObject().value("name").toString(), queueList_);
        item->setData(Qt::UserRole, v.toObject().value("queueId").toString());
    }
    if (queueList_->count() > 0) {
        queueList_->setCurrentRow(0);
    }
}

QJsonObject SchedulerDialog::selectedQueue() const {
    if (!queueList_->currentItem()) {
        return {};
    }
    const QString id = queueList_->currentItem()->data(Qt::UserRole).toString();
    for (const QJsonValue &v : queues_) {
        if (v.toObject().value("queueId").toString() == id) {
            return v.toObject();
        }
    }
    return {};
}

void SchedulerDialog::onQueueSelected(QListWidgetItem *item, QListWidgetItem * /*previous*/) {
    if (!item) {
        form_->setEnabled(false);
        return;
    }
    populateForm(selectedQueue());
    form_->setEnabled(true);
}

void SchedulerDialog::populateForm(const QJsonObject &queue) {
    maxConcurrent_->setValue(queue.value("maxConcurrent").toInt(1));
    const int completeIdx = onComplete_->findData(queue.value("onComplete").toString("nothing"));
    onComplete_->setCurrentIndex(completeIdx >= 0 ? completeIdx : 0);

    const QJsonValue schedule = queue.value("schedule");
    const bool has = schedule.isObject();
    useSchedule_->setChecked(has);
    for (QWidget *w : {static_cast<QWidget *>(mode_), static_cast<QWidget *>(startTime_),
                       static_cast<QWidget *>(stopTime_), static_cast<QWidget *>(runUntilDrains_),
                       static_cast<QWidget *>(onceDate_)}) {
        w->setEnabled(has);
    }
    if (!has) {
        return;
    }
    const QJsonObject sched = schedule.toObject();
    const int modeIdx = mode_->findData(sched.value("mode").toString("once"));
    mode_->setCurrentIndex(modeIdx >= 0 ? modeIdx : 0);
    startTime_->setTime(QTime::fromString(sched.value("startTime").toString("00:00"), "HH:mm"));
    const bool stopIsNull = sched.value("stopTime").isNull();
    runUntilDrains_->setChecked(stopIsNull);
    if (!stopIsNull) {
        stopTime_->setTime(QTime::fromString(sched.value("stopTime").toString(), "HH:mm"));
    }
    for (int i = 0; i < 7; ++i) {
        dayChecks_[i]->setChecked(false);
    }
    for (const QJsonValue &d : sched.value("daysOfWeek").toArray()) {
        const int idx = d.toInt();
        if (idx >= 0 && idx < 7) {
            dayChecks_[idx]->setChecked(true);
        }
    }
    if (!sched.value("onceDate").isNull()) {
        onceDate_->setDate(QDate::fromString(sched.value("onceDate").toString(), Qt::ISODate));
    }
}

void SchedulerDialog::save() {
    const QJsonObject queue = selectedQueue();
    const QString queueId = queue.value("queueId").toString();
    if (queueId.isEmpty()) {
        return;
    }

    QList<int> days;
    for (int i = 0; i < 7; ++i) {
        if (dayChecks_[i]->isChecked()) {
            days << i;
        }
    }
    const QJsonValue schedule = buildSchedule(
        useSchedule_->isChecked(), mode_->currentData().toString(),
        startTime_->time().toString(QStringLiteral("HH:mm")), runUntilDrains_->isChecked(),
        stopTime_->time().toString(QStringLiteral("HH:mm")), days,
        onceDate_->date().toString(Qt::ISODate));

    QPointer<SchedulerDialog> self(this);
    client_->call(QString::fromLatin1(rpc::method::kScheduleSet),
                  QJsonObject{{"queueId", queueId}, {"schedule", schedule}},
                  [self, queueId](const rpc::RpcReply &reply) {
                      if (!self) {
                          return;
                      }
                      if (!reply.ok()) {
                          self->statusLabel_->setText(
                              tr("Could not save the schedule: %1").arg(reply.error.message));
                          self->statusLabel_->show();
                          return;
                      }
                      self->statusLabel_->hide();
                  });

    // Queue-level fields (maxConcurrent/onComplete) go through queue.upsert; taskIds is
    // ignored by the daemon so re-sending the cached membership cannot drop a task.
    QJsonObject updatedQueue = queue;
    updatedQueue["maxConcurrent"] = maxConcurrent_->value();
    updatedQueue["onComplete"] = onComplete_->currentData().toString();
    client_->call(QString::fromLatin1(rpc::method::kQueueUpsert),
                  QJsonObject{{"queue", updatedQueue}}, [self](const rpc::RpcReply &reply) {
                      if (!self || !reply.ok()) {
                          return;
                      }
                      const QJsonObject updated = reply.result.toObject().value("queue").toObject();
                      for (int i = 0; i < self->queues_.size(); ++i) {
                          if (self->queues_[i].toObject().value("queueId").toString() ==
                              updated.value("queueId").toString()) {
                              self->queues_[i] = updated;
                              break;
                          }
                      }
                  });
}

void SchedulerDialog::startNow() {
    const QString queueId = selectedQueue().value("queueId").toString();
    if (queueId.isEmpty()) {
        return;
    }
    client_->call(QString::fromLatin1(rpc::method::kQueueStart), QJsonObject{{"queueId", queueId}});
}

void SchedulerDialog::stopNow() {
    const QString queueId = selectedQueue().value("queueId").toString();
    if (queueId.isEmpty()) {
        return;
    }
    client_->call(
        QString::fromLatin1(rpc::method::kQueueStop),
        QJsonObject{{"queueId", queueId}, {"pauseRunning", pauseRunningOnStop_->isChecked()}});
}

}  // namespace velox::gui