/****************************************************************************
 *
 *   (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

/// QGCmapPolyline map visuals
Item {
    id: _root

    property var    qgcView                     ///< QGCView for popping dialogs
    property var    mapControl                  ///< Map control to place item in
    property var    mapPolyline                 ///< QGCMapPolyline object
    property bool   interactive:    mapPolyline.interactive
    property int    lineWidth:      3
    property color  lineColor:      "#be781c"


    property var    _polylineComponent
    property var    _dragHandlesComponent
    property var    _splitHandlesComponent

    property real _zorderDragHandle:    QGroundControl.zOrderMapItems + 3   // Highest to prevent splitting when items overlap
    property real _zorderSplitHandle:   QGroundControl.zOrderMapItems + 2

    function addVisuals() {
        _polylineComponent = polylineComponent.createObject(mapControl)
        mapControl.addMapItem(_polylineComponent)
    }

    function removeVisuals() {
        _polylineComponent.destroy()
    }

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

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

    /// Calculate the default/initial polyline
    function defaultPolylineVertices() {
        var x = map.centerViewport.x + (map.centerViewport.width / 2)
        var yInset = map.centerViewport.height / 4
        var topPointCoord =     map.toCoordinate(Qt.point(x, map.centerViewport.y + yInset),                                false /* clipToViewPort */)
        var bottomPointCoord =  map.toCoordinate(Qt.point(x, map.centerViewport.y + map.centerViewport.height - yInset),    false /* clipToViewPort */)
        return [ topPointCoord, bottomPointCoord ]
    }

    /// Add an initial 2 point polyline
    function addInitialPolyline() {
        if (mapPolyline.count < 2) {
            mapPolyline.clear()
            var initialVertices = defaultPolylineVertices()
            mapPolyline.appendVertex(initialVertices[0])
            mapPolyline.appendVertex(initialVertices[1])
        }
    }

    /// Reset polyline back to initial default
    function resetPolyline() {
        mapPolyline.clear()
        addInitialPolyline()
    }

    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: {
            mapPolyline.loadKMLFile(file)
            close()
        }
    }

    Component {
        id: polylineComponent

        MapPolyline {
            line.width: lineWidth
            line.color: lineColor
            path:       mapPolyline.path
        }
    }

    Component {
        id: splitHandleComponent

        MapQuickItem {
            id:             mapQuickItem
            anchorPoint.x:  splitHandle.width / 2
            anchorPoint.y:  splitHandle.height / 2

            property int vertexIndex

            sourceItem: Rectangle {
                id:             splitHandle
                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:  mapPolyline.splitSegment(mapQuickItem.vertexIndex)
                }
            }
        }
    }

    Component {
        id: splitHandlesComponent

        Repeater {
            model: mapPolyline.path

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

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

                Component.onCompleted: {
                    if (index + 1 <= _vertices.length - 1) {
                        _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

            property int polylineVertex

            property bool _creationComplete: false

            Component.onCompleted: _creationComplete = true

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

            onClicked: mapPolyline.removeVertex(polylineVertex)
        }
    }

    Component {
        id: dragHandleComponent

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

            property int polylineVertex

            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: mapPolyline.pathModel

            delegate: Item {
                property var _visuals: [ ]

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