import QtQuick
import QtQuick.Controls
import QtQuick.Layouts
import qs.Commons
import qs.Services.UI
import qs.Widgets

RowLayout {
  id: root

  property real minimumWidth: 200
  property real popupHeight: 180

  property string label: ""
  property string description: ""
  property string tooltip: ""
  property var model
  property string currentKey: ""
  property string placeholder: ""
  property var defaultValue: undefined
  property string settingsPath: ""
  property real baseSize: 1.0

  readonly property real preferredHeight: Math.round(Style.baseWidgetSize * 1.1 * root.baseSize)
  readonly property var comboBox: combo

  signal selected(string key)

  spacing: Style.marginL
  opacity: enabled ? 1.0 : 0.6

  // Less strict comparison with != (instead of !==) so it can properly compare int vs string (ex for FPS: 30 and "30")
  readonly property bool isValueChanged: (defaultValue !== undefined) && (currentKey != defaultValue)

  readonly property string indicatorTooltip: {
    if (defaultValue === undefined)
      return "";
    var displayValue = "";
    if (defaultValue === "") {
      // Try to find the display name for empty key in the model
      var found = false;
      if (root.model) {
        if (Array.isArray(root.model)) {
          for (var i = 0; i < root.model.length; i++) {
            var item = root.model[i];
            if (item && item.key === "") {
              displayValue = item.name || I18n.tr("panels.indicator.system-default");
              found = true;
              break;
            }
          }
        } else if (typeof root.model.get === 'function') {
          for (var i = 0; i < root.itemCount(); i++) {
            var item = root.getItem(i);
            if (item && item.key === "") {
              displayValue = item.name || I18n.tr("panels.indicator.system-default");
              found = true;
              break;
            }
          }
        }
      }
      // If not found in model, show "System Default" instead of "(empty)"
      if (!found) {
        displayValue = I18n.tr("panels.indicator.system-default");
      }
    } else {
      // Try to find the display name for the default key in the model
      var found = false;
      if (root.model) {
        if (Array.isArray(root.model)) {
          for (var i = 0; i < root.model.length; i++) {
            var item = root.model[i];
            if (item && item.key === defaultValue) {
              displayValue = item.name || String(defaultValue);
              found = true;
              break;
            }
          }
        } else if (typeof root.model.get === 'function') {
          for (var i = 0; i < root.itemCount(); i++) {
            var item = root.getItem(i);
            if (item && item.key === defaultValue) {
              displayValue = item.name || String(defaultValue);
              found = true;
              break;
            }
          }
        }
      }
      if (!found) {
        displayValue = String(defaultValue);
      }
    }
    return I18n.tr("panels.indicator.default-value", {
                     "value": displayValue
                   });
  }

  function itemCount() {
    if (!root.model)
      return 0;
    if (typeof root.model.count === 'number')
      return root.model.count;
    if (Array.isArray(root.model))
      return root.model.length;
    return 0;
  }

  function getItem(index) {
    if (!root.model)
      return null;
    if (typeof root.model.get === 'function')
      return root.model.get(index);
    if (Array.isArray(root.model))
      return root.model[index];
    return null;
  }

  function findIndexByKey(key) {
    for (var i = 0; i < itemCount(); i++) {
      var item = getItem(i);
      if (item && item.key === key)
        return i;
    }
    return -1;
  }

  NLabel {
    label: root.label
    description: root.description
    showIndicator: root.isValueChanged
    indicatorTooltip: root.indicatorTooltip
  }

  ComboBox {
    id: combo

    Layout.minimumWidth: Math.round(root.minimumWidth * Style.uiScaleRatio)
    Layout.preferredHeight: Math.round(root.preferredHeight * Style.uiScaleRatio)
    implicitWidth: Layout.minimumWidth
    model: root.model
    textRole: "name"
    currentIndex: root.findIndexByKey(root.currentKey)

    onActivated: {
      var item = root.getItem(combo.currentIndex);
      if (item && item.key !== undefined)
        root.selected(item.key);
    }

    Keys.onUpPressed: event => {
                        if (combo.popup.visible) {
                          if (listView.currentIndex > 0) {
                            listView.currentIndex--;
                            listView.positionViewAtIndex(listView.currentIndex, ListView.Contain);
                          }
                          event.accepted = true;
                        } else {
                          event.accepted = false;
                        }
                      }

    Keys.onDownPressed: event => {
                          if (combo.popup.visible) {
                            if (listView.currentIndex < root.itemCount() - 1) {
                              listView.currentIndex++;
                              listView.positionViewAtIndex(listView.currentIndex, ListView.Contain);
                            }
                            event.accepted = true;
                          } else {
                            event.accepted = false;
                          }
                        }

    Keys.onReturnPressed: event => {
                            if (combo.popup.visible) {
                              var item = root.getItem(listView.currentIndex);
                              if (item && item.key !== undefined) {
                                root.selected(item.key);
                                combo.currentIndex = listView.currentIndex;
                                combo.popup.close();
                              }
                              event.accepted = true;
                            } else {
                              event.accepted = false;
                            }
                          }

    Keys.onEnterPressed: event => {
                           combo.Keys.returnPressed(event);
                         }

    background: Rectangle {
      implicitWidth: Math.round(Style.baseWidgetSize * 3.75 * Style.uiScaleRatio)
      implicitHeight: Math.round(root.preferredHeight * Style.uiScaleRatio)
      color: Color.mSurface
      border.color: combo.activeFocus ? Color.mSecondary : Color.mOutline
      border.width: Style.borderS
      radius: Style.iRadiusM

      Behavior on border.color {
        ColorAnimation {
          duration: Style.animationFast
        }
      }

      MouseArea {
        anchors.fill: parent
        hoverEnabled: true
        acceptedButtons: Qt.NoButton
        onEntered: {
          if (root.tooltip != "") {
            TooltipService.show(root, root.tooltip);
          }
        }
        onExited: {
          if (root.tooltip != "") {
            TooltipService.hide();
          }
        }
      }
    }

    contentItem: NText {
      leftPadding: Style.marginL
      rightPadding: combo.indicator.width + Style.marginL
      pointSize: Style.fontSizeM
      verticalAlignment: Text.AlignVCenter
      elide: Text.ElideRight
      color: combo.currentIndex >= 0 ? Color.mOnSurface : Color.mOnSurfaceVariant
      text: {
        if (combo.currentIndex >= 0 && combo.currentIndex < root.itemCount()) {
          var item = root.getItem(combo.currentIndex);
          return item ? item.name : root.placeholder;
        }
        return root.placeholder;
      }
    }

    indicator: NIcon {
      x: combo.width - width - Style.marginM
      y: combo.topPadding + (combo.availableHeight - height) / 2
      icon: "caret-down"
      pointSize: Style.fontSizeL
    }

    popup: Popup {
      y: combo.height + Style.marginS
      implicitWidth: combo.width
      implicitHeight: Math.min(Math.round(root.popupHeight * Style.uiScaleRatio), listView.contentHeight + Style.margin2M)
      padding: Style.marginM

      onOpened: {
        listView.currentIndex = combo.currentIndex;
        listView.positionViewAtIndex(combo.currentIndex, ListView.Beginning);
      }

      contentItem: NListView {
        id: listView
        property var comboBox: combo
        model: combo.popup.visible ? root.model : null
        highlightMoveDuration: 0
        //showGradientMasks: false

        delegate: Rectangle {
          id: delegateRect
          required property int index
          property bool isHighlighted: listView.currentIndex === index

          width: listView.availableWidth
          height: delegateText.implicitHeight + Style.margin2S
          radius: Style.iRadiusS
          color: isHighlighted ? Color.mHover : "transparent"

          Behavior on color {
            ColorAnimation {
              duration: Style.animationFast
            }
          }

          NText {
            id: delegateText
            anchors.fill: parent
            anchors.leftMargin: Style.marginM
            anchors.rightMargin: Style.marginM
            verticalAlignment: Text.AlignVCenter
            elide: Text.ElideRight
            pointSize: Style.fontSizeM
            color: delegateRect.isHighlighted ? Color.mOnHover : Color.mOnSurface
            text: {
              var item = root.getItem(delegateRect.index);
              return item && item.name ? item.name : "";
            }

            Behavior on color {
              ColorAnimation {
                duration: Style.animationFast
              }
            }
          }

          MouseArea {
            anchors.fill: parent
            hoverEnabled: true
            onContainsMouseChanged: {
              if (containsMouse) {
                listView.currentIndex = delegateRect.index;
              }
            }
            onClicked: {
              var item = root.getItem(delegateRect.index);
              if (item && item.key !== undefined) {
                root.selected(item.key);
                listView.comboBox.currentIndex = delegateRect.index;
                listView.comboBox.popup.close();
              }
            }
          }
        }
      }

      background: Rectangle {
        color: Color.mSurfaceVariant
        border.color: Color.mOutline
        border.width: Style.borderS
        radius: Style.iRadiusM
      }
    }

    Connections {
      target: root
      function onCurrentKeyChanged() {
        combo.currentIndex = root.findIndexByKey(root.currentKey);
      }
      function onModelChanged() {
        combo.currentIndex = root.findIndexByKey(root.currentKey);
      }
    }
  }
}