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import QtQuick 2.1
import QtQuick.Controls 1.0
import QtQuick.Controls.Private 1.0
import "Styles/Settings.js" as Settings

/*!
    \qmltype ComboBox
    \inqmlmodule QtQuick.Controls 1.0
    \ingroup controls
    \brief ComboBox is a combined button and popup or drop-down list.

    Add items to the comboBox by assigning it a ListModel, or a list of strings to the \l model property.

    \qml
       ComboBox {
           width: 200
           model: [ "Banana", "Apple", "Coconut" ]
       }
    \endqml

    Example 2:

    \qml
       ComboBox {
           model: ListModel {
               id: cbItems
               ListElement { text: "Banana"; color: "Yellow" }
               ListElement { text: "Apple"; color: "Green" }
               ListElement { text: "Coconut"; color: "Brown" }
           }
           width: 200
           onCurrentIndexChanged: console.debug(currentText + ", " + cbItems.get(currentIndex).color)
       }
    \endqml
*/

Control {
    id: comboBox

    /*! The model to populate the ComboBox from. */
    property alias model: popup.model
    property alias textRole: popup.textRole

    /*! The index of the currently selected item in the ComboBox. */
    property alias currentIndex: popup.__selectedIndex
    /*! The text of the currently selected item in the ComboBox. */
    readonly property alias currentText: popup.selectedText

    /* \internal */
    readonly property bool __pressed: mouseArea.pressed && mouseArea.containsMouse || popup.__popupVisible
    /* \internal */
    property alias __containsMouse: mouseArea.containsMouse

    style: Qt.createComponent(Settings.THEME_PATH + "/ComboBoxStyle.qml", comboBox)

    activeFocusOnTab: true

    Accessible.role: Accessible.ComboBox

    MouseArea {
        id: mouseArea
        anchors.fill: parent
        hoverEnabled: true
        onPressedChanged: if (pressed) popup.show()
    }

    StyleItem { id: styleItem }

    Component.onCompleted: {
        if (currentIndex === -1)
            currentIndex = 0
        if (styleItem.style == "mac") {
            popup.x -= 10
            popup.y += 4
            popup.__font.pointSize = 13
        }
    }

    Menu {
        id: popup

        style: isPopup ? __style.popupStyle : __style.dropDownStyle

        readonly property string selectedText: items[__selectedIndex] ? items[__selectedIndex].text : ""
        property string textRole: ""
        property var model
        property int modelSize: 0
        property bool ready: false
        property bool isPopup: comboBox.__panel.popup

        property int x: 0
        property int y: isPopup ? 0 : comboBox.height
        __minimumWidth: comboBox.width
        __visualItem: comboBox

        property ExclusiveGroup eg: ExclusiveGroup { id: eg }

        onModelChanged: rebuildMenu()
        onTextRoleChanged: rebuildMenu()

        Component.onCompleted: { ready = true; rebuildMenu() }

        function rebuildMenu() {
            if (!ready) return;
            clear()
            if (!model) {
                __selectedIndexChanged();
                return;
            }

            var isNumberModel = typeof(model) === "number"
            var modelMayHaveRoles = model.count !== undefined
            modelSize = isNumberModel ? model :
                        modelMayHaveRoles ? model.count : model.length
            var effectiveTextRole = textRole
            if (effectiveTextRole === ""
                && modelMayHaveRoles
                && model.get && model.get(0)) {
                // No text role set, check whether model has a suitable role
                // If 'text' is found, or there's only one role, pick that.
                var listElement = model.get(0)
                var roleName = ""
                var roleCount = 0
                for (var role in listElement) {
                    if (role === "text") {
                        roleName = role
                        break
                    } else if (!roleName) {
                        roleName = role
                    }
                    ++roleCount
                }
                if (roleCount > 1 && roleName !== "text") {
                    console.warn("No suitable 'textRole' found for ComboBox.")
                } else {
                    effectiveTextRole = roleName
                }
            }
            for (var i = 0; i < modelSize; ++i) {
                var textValue
                if (isNumberModel)
                    textValue = i + ""
                else if (effectiveTextRole !== "")
                    textValue = model.get(i)[effectiveTextRole]
                else
                    textValue = model[i]

                var item = addItem(textValue)
                item.checkable = true
                item.exclusiveGroup = eg
            }
            __selectedIndexChanged();
        }

        function show() {
            if (items[__selectedIndex])
                items[__selectedIndex].checked = true
            __currentIndex = comboBox.currentIndex
            __popup(x, y, isPopup ? __selectedIndex : 0)
        }
    }

    // The key bindings below will only be in use when popup is
    // not visible. Otherwise, native popup key handling will take place:
    Keys.onSpacePressed: {
        if (!popup.popupVisible)
            popup.show()
    }
    Keys.onUpPressed: { if (currentIndex > 0) currentIndex-- }
    Keys.onDownPressed: { if (currentIndex < popup.modelSize - 1) currentIndex++ }
}