/****************************************************************************
 *
 *   (c) 2009-2016 QGROUNDCONTROL PROJECT <http://www.qgroundcontrol.org>
 *
 * QGroundControl is licensed according to the terms in the file
 * COPYING.md in the root of the source code directory.
 *
 ****************************************************************************/

import QtQuick          2.3
import QtQuick.Controls 1.2
import QtLocation       5.3
import QtPositioning    5.3
import QtQuick.Dialogs  1.2

import QGroundControl               1.0
import QGroundControl.ScreenTools   1.0
import QGroundControl.Palette       1.0
import QGroundControl.Controls      1.0
import QGroundControl.FlightMap     1.0

/// QGCMapPolygon map visuals
Item {
    id: _root

    property var    qgcView                                     ///< QGCView for popping dialogs
    property var    mapControl                                  ///< Map control to place item in
    property var    mapPolygon                                  ///< QGCMapPolygon object
    property bool   interactive:        mapPolygon.interactive
    property color  interiorColor:      "transparent"
    property real   interiorOpacity:    1
    property int    borderWidth:        0
    property color  borderColor:        "black"

    property var    _polygonComponent
    property var    _dragHandlesComponent
    property var    _splitHandlesComponent
    property var    _centerDragHandleComponent
    property bool   _circle:                    false
    property real   _circleRadius

    property real _zorderDragHandle:    QGroundControl.zOrderMapItems + 3   // Highest to prevent splitting when items overlap
    property real _zorderSplitHandle:   QGroundControl.zOrderMapItems + 2
    property real _zorderCenterHandle:  QGroundControl.zOrderMapItems + 1   // Lowest such that drag or split takes precedence

    function addVisuals() {
        _polygonComponent = polygonComponent.createObject(mapControl)
        mapControl.addMapItem(_polygonComponent)
    }

    function removeVisuals() {
        _polygonComponent.destroy()
    }

    function addHandles() {
        if (!_dragHandlesComponent) {
            _dragHandlesComponent = dragHandlesComponent.createObject(mapControl)
            _splitHandlesComponent = splitHandlesComponent.createObject(mapControl)
            _centerDragHandleComponent = centerDragHandleComponent.createObject(mapControl)
        }
    }

    function removeHandles() {
        if (_dragHandlesComponent) {
            _dragHandlesComponent.destroy()
            _dragHandlesComponent = undefined
        }
        if (_splitHandlesComponent) {
            _splitHandlesComponent.destroy()
            _splitHandlesComponent = undefined
        }
        if (_centerDragHandleComponent) {
            _centerDragHandleComponent.destroy()
            _centerDragHandleComponent = undefined
        }
    }

    /// Calculate the default/initial 4 sided polygon
    function defaultPolygonVertices() {
        // Initial polygon is inset to take 2/3rds space
        var rect = Qt.rect(map.centerViewport.x, map.centerViewport.y, map.centerViewport.width, map.centerViewport.height)
        rect.x += (rect.width * 0.25) / 2
        rect.y += (rect.height * 0.25) / 2
        rect.width *= 0.75
        rect.height *= 0.75

        var centerCoord =       map.toCoordinate(Qt.point(rect.x + (rect.width / 2), rect.y + (rect.height / 2)),   false /* clipToViewPort */)
        var topLeftCoord =      map.toCoordinate(Qt.point(rect.x, rect.y),                                          false /* clipToViewPort */)
        var topRightCoord =     map.toCoordinate(Qt.point(rect.x + rect.width, rect.y),                             false /* clipToViewPort */)
        var bottomLeftCoord =   map.toCoordinate(Qt.point(rect.x, rect.y + rect.height),                            false /* clipToViewPort */)
        var bottomRightCoord =  map.toCoordinate(Qt.point(rect.x + rect.width, rect.y + rect.height),               false /* clipToViewPort */)

        // Initial polygon has max width and height of 3000 meters
        var halfWidthMeters =   Math.min(topLeftCoord.distanceTo(topRightCoord), 3000) / 2
        var halfHeightMeters =  Math.min(topLeftCoord.distanceTo(bottomLeftCoord), 3000) / 2
        topLeftCoord =      centerCoord.atDistanceAndAzimuth(halfWidthMeters, -90).atDistanceAndAzimuth(halfHeightMeters, 0)
        topRightCoord =     centerCoord.atDistanceAndAzimuth(halfWidthMeters, 90).atDistanceAndAzimuth(halfHeightMeters, 0)
        bottomLeftCoord =   centerCoord.atDistanceAndAzimuth(halfWidthMeters, -90).atDistanceAndAzimuth(halfHeightMeters, 180)
        bottomRightCoord =  centerCoord.atDistanceAndAzimuth(halfWidthMeters, 90).atDistanceAndAzimuth(halfHeightMeters, 180)

        return [ topLeftCoord, topRightCoord, bottomRightCoord, bottomLeftCoord, centerCoord  ]
    }

    /// Add an initial 4 sided polygon
    function addInitialPolygon() {
        if (mapPolygon.count < 3) {
            initialVertices = defaultPolygonVertices()
            mapPolygon.appendVertex(initialVertices[0])
            mapPolygon.appendVertex(initialVertices[1])
            mapPolygon.appendVertex(initialVertices[2])
            mapPolygon.appendVertex(initialVertices[3])
        }
    }

    /// Reset polygon back to initial default
    function resetPolygon() {
        var initialVertices = defaultPolygonVertices()
        mapPolygon.clear()
        for (var i=0; i<4; i++) {
            mapPolygon.appendVertex(initialVertices[i])
        }
        _circle = false
    }

    /// Reset polygon to a circle which fits within initial polygon
    function setCircleRadius(center, radius) {
        var unboundCenter = center.atDistanceAndAzimuth(0, 0)
        _circleRadius = radius
        var segments = 16
        var angleIncrement = 360 / segments
        var angle = 0
        mapPolygon.clear()
        for (var i=0; i<segments; i++) {
            var vertex = unboundCenter.atDistanceAndAzimuth(_circleRadius, angle)
            mapPolygon.appendVertex(vertex)
            angle += angleIncrement
        }
        _circle = true
    }

    /// Reset polygon to a circle which fits within initial polygon
    function resetCircle() {
        var initialVertices = defaultPolygonVertices()
        var width = initialVertices[0].distanceTo(initialVertices[1])
        var height = initialVertices[1].distanceTo(initialVertices[2])
        var radius = Math.min(width, height) / 2
        var center = initialVertices[4]
        setCircleRadius(center, radius)
    }

    function loadKMLFile() {
        mapPolygon.loadKMLFile("/Users/Don/Downloads/polygon.kml")
    }

    onInteractiveChanged: {
        if (interactive) {
            addHandles()
        } else {
            removeHandles()
        }
    }

    Component.onCompleted: {
        addVisuals()
        if (interactive) {
            addHandles()
        }
    }

    Component.onDestruction: {
        removeVisuals()
        removeHandles()
    }

    QGCPalette { id: qgcPal }

    QGCFileDialog {
        id:             kmlLoadDialog
        qgcView:        _root.qgcView
        folder:         QGroundControl.settingsManager.appSettings.missionSavePath
        title:          qsTr("Select KML File")
        selectExisting: true
        nameFilters:    [ qsTr("KML files (*.kml)") ]


        onAcceptedForLoad: {
            mapPolygon.loadKMLFile(file)
            close()
        }
    }

    Component {
        id: polygonComponent

        MapPolygon {
            color:          interiorColor
            opacity:        interiorOpacity
            border.color:   borderColor
            border.width:   borderWidth
            path:           mapPolygon.path
        }
    }

    Component {
        id: splitHandleComponent

        MapQuickItem {
            id:             mapQuickItem
            anchorPoint.x:  dragHandle.width / 2
            anchorPoint.y:  dragHandle.height / 2
            visible:        !_circle

            property int vertexIndex

            sourceItem: Rectangle {
                id:         dragHandle
                width:      ScreenTools.defaultFontPixelHeight * 1.5
                height:     width
                radius:     width / 2
                border.color:      "white"
                color:      "transparent"
                opacity:    .50
                z:          _zorderSplitHandle

                QGCLabel {
                    anchors.horizontalCenter:   parent.horizontalCenter
                    anchors.verticalCenter:     parent.verticalCenter
                    text:                       "+"
                }

                QGCMouseArea {
                    fillItem:   parent
                    onClicked:  mapPolygon.splitPolygonSegment(mapQuickItem.vertexIndex)
                }
            }
        }
    }

    Component {
        id: splitHandlesComponent

        Repeater {
            model: mapPolygon.path

            delegate: Item {
                property var _splitHandle
                property var _vertices:     mapPolygon.path

                function _setHandlePosition() {
                    var nextIndex = index + 1
                    if (nextIndex > _vertices.length - 1) {
                        nextIndex = 0
                    }
                    var distance = _vertices[index].distanceTo(_vertices[nextIndex])
                    var azimuth = _vertices[index].azimuthTo(_vertices[nextIndex])
                    _splitHandle.coordinate = _vertices[index].atDistanceAndAzimuth(distance / 2, azimuth)
                }

                Component.onCompleted: {
                    _splitHandle = splitHandleComponent.createObject(mapControl)
                    _splitHandle.vertexIndex = index
                    _setHandlePosition()
                    mapControl.addMapItem(_splitHandle)
                }

                Component.onDestruction: {
                    if (_splitHandle) {
                        _splitHandle.destroy()
                    }
                }
            }
        }
    }

    // Control which is used to drag polygon vertices
    Component {
        id: dragAreaComponent

        MissionItemIndicatorDrag {
            id:         dragArea
            z:          _zorderDragHandle
            visible:    !_circle

            property int polygonVertex

            property bool _creationComplete: false

            Component.onCompleted: _creationComplete = true

            onItemCoordinateChanged: {
                if (_creationComplete) {
                    // During component creation some bad coordinate values got through which screws up draw
                    mapPolygon.adjustVertex(polygonVertex, itemCoordinate)
                }
            }

            onClicked: mapPolygon.removeVertex(polygonVertex)
        }
    }

    Component {
        id: centerDragHandle

        MapQuickItem {
            id:             mapQuickItem
            anchorPoint.x:  dragHandle.width / 2
            anchorPoint.y:  dragHandle.height / 2
            z:              _zorderDragHandle

            sourceItem: Rectangle {
                id:         dragHandle
                width:      ScreenTools.defaultFontPixelHeight * 1.5
                height:     width
                radius:     width / 2
                color:      "white"
                opacity:    .90

                QGCLabel {
                    anchors.horizontalCenter:   parent.horizontalCenter
                    anchors.verticalCenter:     parent.verticalCenter
                    text:                       "..."
                    color:                      "black"
                }
            }
        }
    }

    Component {
        id: dragHandleComponent

        MapQuickItem {
            id:             mapQuickItem
            anchorPoint.x:  dragHandle.width / 2
            anchorPoint.y:  dragHandle.height / 2
            z:              _zorderDragHandle
            visible:        !_circle

            property int polygonVertex

            sourceItem: Rectangle {
                id:         dragHandle
                width:      ScreenTools.defaultFontPixelHeight * 1.5
                height:     width
                radius:     width / 2
                color:      "white"
                opacity:    .90
            }
        }
    }

    // Add all polygon vertex drag handles to the map
    Component {
        id: dragHandlesComponent

        Repeater {
            model: mapPolygon.pathModel

            delegate: Item {
                property var _visuals: [ ]

                Component.onCompleted: {
                    var dragHandle = dragHandleComponent.createObject(mapControl)
                    dragHandle.coordinate = Qt.binding(function() { return object.coordinate })
                    dragHandle.polygonVertex = Qt.binding(function() { return index })
                    mapControl.addMapItem(dragHandle)
                    var dragArea = dragAreaComponent.createObject(mapControl, { "itemIndicator": dragHandle, "itemCoordinate": object.coordinate })
                    dragArea.polygonVertex = Qt.binding(function() { return index })
                    _visuals.push(dragHandle)
                    _visuals.push(dragArea)
                }

                Component.onDestruction: {
                    for (var i=0; i<_visuals.length; i++) {
                        _visuals[i].destroy()
                    }
                    _visuals = [ ]
                }
            }
        }
    }

    Component {
        id: editPositionDialog

        EditPositionDialog {
            coordinate: mapPolygon.center
            onCoordinateChanged: mapPolygon.center = coordinate
        }
    }

    Component {
        id: centerDragAreaComponent

        MissionItemIndicatorDrag {
            z:                          _zorderCenterHandle
            onItemCoordinateChanged:    mapPolygon.center = itemCoordinate
            onDragStart:                mapPolygon.centerDrag = true
            onDragStop:                 mapPolygon.centerDrag = false
            onClicked:                  menu.popup()

            function setRadiusFromDialog() {
                setCircleRadius(mapPolygon.center, radiusField.text)
                radiusDialog.visible = false
            }

            Menu {
                id: menu

                MenuItem {
                    text:           qsTr("Circle" )
                    onTriggered:    resetCircle()
                }

                MenuItem {
                    text:           qsTr("Polygon")
                    onTriggered:    resetPolygon()
                }

                MenuItem {
                    text:           qsTr("Set radius..." )
                    enabled:        _circle
                    onTriggered:    radiusDialog.visible = true
                }

                MenuItem {
                    text:           qsTr("Edit position..." )
                    enabled:        _circle
                    onTriggered:    qgcView.showDialog(editPositionDialog, qsTr("Edit Position"), qgcView.showDialogDefaultWidth, StandardButton.Cancel)
                }

                MenuItem {
                    text:           qsTr("Load KML...")
                    onTriggered:    kmlLoadDialog.openForLoad()
                }
            }

            Rectangle {
                id:                 radiusDialog
                anchors.margins:    _margin
                anchors.left:       parent.right
                width:              radiusColumn.width + (_margin *2)
                height:             radiusColumn.height + (_margin *2)
                color:              qgcPal.window
                border.color:       qgcPal.text
                visible:            false

                Column {
                    id:                 radiusColumn
                    anchors.margins:    _margin
                    anchors.left:       parent.left
                    anchors.top:        parent.top
                    spacing:            _margin

                    QGCLabel { text: qsTr("Radius:") }

                    QGCTextField {
                        id:                 radiusField
                        text:               _circleRadius.toFixed(2)
                        onEditingFinished:  setRadiusFromDialog()
                    }
                }

                QGCLabel {
                    anchors.right:  radiusColumn.right
                    anchors.top:    radiusColumn.top
                    text:           "X"

                    QGCMouseArea {
                        fillItem:   parent
                        onClicked:  setRadiusFromDialog()
                    }
                }
            }
        }
    }

    Component {
        id: centerDragHandleComponent

        Item {
            property var dragHandle
            property var dragArea

            Component.onCompleted: {
                dragHandle = centerDragHandle.createObject(mapControl)
                dragHandle.coordinate = Qt.binding(function() { return mapPolygon.center })
                mapControl.addMapItem(dragHandle)
                dragArea = centerDragAreaComponent.createObject(mapControl, { "itemIndicator": dragHandle, "itemCoordinate": mapPolygon.center })
            }

            Component.onDestruction: {
                dragHandle.destroy()
                dragArea.destroy()
            }
        }
    }
}