import "../Common/fuzzysort.js" as FuzzySort
import QtQuick
import QtQuick.Controls
import qs.Common
import qs.Widgets

Rectangle {
  id: root

  property string text: ""
  property string description: ""
  property string currentValue: ""
  property var options: []
  property var optionIcons: [] // Array of icon names corresponding to options
  property bool forceRecreate: false
  property bool enableFuzzySearch: false
  property int popupWidthOffset: 0 // How much wider the popup should be than the button
  property int maxPopupHeight: 400

  signal valueChanged(string value)

  width: parent.width
  height: 60
  radius: Theme.cornerRadius
  color: "transparent"
  Component.onCompleted: {
    forceRecreateTimer.start()
  }
  Component.onDestruction: {
    var popup = popupLoader.item
    if (popup && popup.visible)
      popup.close()
  }
  onVisibleChanged: {
    var popup = popupLoader.item
    if (!visible && popup && popup.visible)
      popup.close()
    else if (visible)
      forceRecreateTimer.start()
  }

  Timer {
    id: forceRecreateTimer

    interval: 50
    repeat: false
    onTriggered: {
      root.forceRecreate = !root.forceRecreate
    }
  }

  Column {
    anchors.left: parent.left
    anchors.right: dropdown.left
    anchors.verticalCenter: parent.verticalCenter
    anchors.leftMargin: Theme.spacingM
    anchors.rightMargin: Theme.spacingM
    spacing: Theme.spacingXS

    StyledText {
      text: root.text
      font.pixelSize: Theme.fontSizeMedium
      color: Theme.surfaceText
      font.weight: Font.Medium
    }

    StyledText {
      text: root.description
      font.pixelSize: Theme.fontSizeSmall
      color: Theme.surfaceVariantText
      visible: description.length > 0
      wrapMode: Text.WordWrap
      width: parent.width
    }
  }

  Rectangle {
    id: dropdown

    width: 180
    height: 36
    anchors.right: parent.right
    anchors.rightMargin: Theme.spacingM
    anchors.verticalCenter: parent.verticalCenter
    radius: Theme.cornerRadius
    color: dropdownArea.containsMouse ? Theme.primaryHover : Theme.contentBackground()
    border.color: Theme.surfaceVariantAlpha
    border.width: 1

    MouseArea {
      id: dropdownArea

      anchors.fill: parent
      hoverEnabled: true
      cursorShape: Qt.PointingHandCursor
      onClicked: {
        var popup = popupLoader.item
        if (popup && popup.visible) {
          popup.close()
        } else if (popup) {
          var pos = dropdown.mapToItem(Overlay.overlay, 0, dropdown.height + 4)
          popup.x = pos.x - (root.popupWidthOffset / 2)
          popup.y = pos.y
          popup.open()
        }
      }
    }

    Row {
      id: contentRow

      anchors.left: parent.left
      anchors.verticalCenter: parent.verticalCenter
      anchors.leftMargin: Theme.spacingM
      spacing: Theme.spacingS

      DankIcon {
        name: {
          var currentIndex = root.options.indexOf(root.currentValue)
          return root.optionIcons.length > currentIndex
              && currentIndex >= 0 ? root.optionIcons[currentIndex] : ""
        }
        size: 18
        color: Theme.surfaceVariantText
        visible: name !== ""
      }

      StyledText {
        text: root.currentValue
        font.pixelSize: Theme.fontSizeMedium
        color: Theme.surfaceText
        width: dropdown.width - contentRow.x - expandIcon.width - Theme.spacingM - Theme.spacingS
        elide: Text.ElideRight
      }
    }

    DankIcon {
      id: expandIcon

      name: "expand_more"
      size: 20
      color: Theme.surfaceVariantText
      anchors.right: parent.right
      anchors.verticalCenter: parent.verticalCenter
      anchors.rightMargin: Theme.spacingS
    }
  }

  Loader {
    id: popupLoader

    property bool recreateFlag: root.forceRecreate

    active: true
    onRecreateFlagChanged: {
      active = false
      active = true
    }

    sourceComponent: Component {
      Popup {
        id: dropdownMenu

        property string searchQuery: ""
        property var filteredOptions: []
        property int selectedIndex: -1

        function updateFilteredOptions() {
          if (!root.enableFuzzySearch || searchQuery.length === 0) {
            filteredOptions = root.options
          } else {
            var results = FuzzySort.go(searchQuery, root.options, {
                                         "limit": 50,
                                         "threshold": -10000
                                       })
            filteredOptions = results.map(function (result) {
              return result.target
            })
          }
          selectedIndex = -1
        }

        function selectNext() {
          if (filteredOptions.length > 0) {
            selectedIndex = (selectedIndex + 1) % filteredOptions.length
            listView.positionViewAtIndex(selectedIndex, ListView.Contain)
          }
        }

        function selectPrevious() {
          if (filteredOptions.length > 0) {
            selectedIndex = selectedIndex <= 0 ? filteredOptions.length - 1 : selectedIndex - 1
            listView.positionViewAtIndex(selectedIndex, ListView.Contain)
          }
        }

        function selectCurrent() {
          if (selectedIndex >= 0 && selectedIndex < filteredOptions.length) {
            root.currentValue = filteredOptions[selectedIndex]
            root.valueChanged(filteredOptions[selectedIndex])
            close()
          }
        }

        parent: Overlay.overlay
        width: dropdown.width + root.popupWidthOffset
        height: Math.min(root.maxPopupHeight,
                         (root.enableFuzzySearch ? 54 : 0) + Math.min(
                           filteredOptions.length, 10) * 36 + 16)
        padding: 0
        modal: true
        closePolicy: Popup.CloseOnEscape | Popup.CloseOnPressOutside
        onOpened: {
          searchQuery = ""
          updateFilteredOptions()
          if (root.enableFuzzySearch && searchField.visible)
            searchField.forceActiveFocus()
        }

        background: Rectangle {
          color: "transparent"
        }

        contentItem: Rectangle {
          color: Qt.rgba(Theme.surfaceContainer.r, Theme.surfaceContainer.g,
                         Theme.surfaceContainer.b, 1)
          border.color: Theme.primarySelected
          border.width: 1
          radius: Theme.cornerRadius

          Column {
            anchors.fill: parent
            anchors.margins: Theme.spacingS

            Rectangle {
              id: searchContainer

              width: parent.width
              height: 42
              visible: root.enableFuzzySearch
              radius: Theme.cornerRadius
              color: Theme.surfaceVariantAlpha

              DankTextField {
                id: searchField

                anchors.fill: parent
                anchors.margins: 1
                placeholderText: "Search..."
                text: searchQuery
                topPadding: Theme.spacingS
                bottomPadding: Theme.spacingS
                onTextChanged: {
                  searchQuery = text
                  updateFilteredOptions()
                }
                Keys.onDownPressed: selectNext()
                Keys.onUpPressed: selectPrevious()
                Keys.onReturnPressed: selectCurrent()
                Keys.onEnterPressed: selectCurrent()
              }
            }

            Item {
              width: 1
              height: Theme.spacingXS
              visible: root.enableFuzzySearch
            }

            DankListView {
              id: listView

              property var popupRef: dropdownMenu

              width: parent.width
              height: parent.height - (root.enableFuzzySearch ? searchContainer.height
                                                                + Theme.spacingXS : 0)
              clip: true
              model: filteredOptions
              spacing: 2

              // Qt 6.9+ scrolling: flickDeceleration/maximumFlickVelocity only affect touch now
              interactive: true
              flickDeceleration: 1500 // Touch only in Qt 6.9+      // Lower = more momentum, longer scrolling
              maximumFlickVelocity: 2000 // Touch only in Qt 6.9+   // Higher = faster maximum scroll speed
              boundsBehavior: Flickable.DragAndOvershootBounds
              boundsMovement: Flickable.FollowBoundsBehavior
              pressDelay: 0
              flickableDirection: Flickable.VerticalFlick

              ScrollBar.vertical: ScrollBar {
                policy: ScrollBar.AsNeeded
              }

              ScrollBar.horizontal: ScrollBar {
                policy: ScrollBar.AlwaysOff
              }

              delegate: Rectangle {
                property bool isSelected: selectedIndex === index
                property bool isCurrentValue: root.currentValue === modelData
                property int optionIndex: root.options.indexOf(modelData)

                width: ListView.view.width
                height: 32
                radius: Theme.cornerRadius
                color: isSelected ? Theme.primaryHover : optionArea.containsMouse ? Theme.primaryHoverLight : "transparent"

                Row {
                  anchors.left: parent.left
                  anchors.leftMargin: Theme.spacingS
                  anchors.verticalCenter: parent.verticalCenter
                  spacing: Theme.spacingS

                  DankIcon {
                    name: optionIndex >= 0 && root.optionIcons.length
                          > optionIndex ? root.optionIcons[optionIndex] : ""
                    size: 18
                    color: isCurrentValue ? Theme.primary : Theme.surfaceVariantText
                    visible: name !== ""
                  }

                  StyledText {
                    anchors.verticalCenter: parent.verticalCenter
                    text: modelData
                    font.pixelSize: Theme.fontSizeMedium
                    color: isCurrentValue ? Theme.primary : Theme.surfaceText
                    font.weight: isCurrentValue ? Font.Medium : Font.Normal
                    width: parent.parent.width - parent.x - Theme.spacingS
                    elide: Text.ElideRight
                  }
                }

                MouseArea {
                  id: optionArea

                  anchors.fill: parent
                  hoverEnabled: true
                  cursorShape: Qt.PointingHandCursor
                  onClicked: {
                    root.currentValue = modelData
                    root.valueChanged(modelData)
                    dropdownMenu.close()
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}