// to call this function no need to select the composite in the node view, it will be chosen with a prompt.

function ConnectButton(){
    if (KeyModifiers.IsAlternatePressed()){
        disconnectAllSellNodes()
    }else{
        connectAllSellNodes()
    }
}


function connectAllSellNodes(){
    // connects selected Nodes to a chosen Composite
    scene.beginUndoRedoAccum("connectAllSelNodes");

    // filter out some nodes types
    var typesFilter = ["PEG"]
    var sel = selection.selectedNodes()
    sel = sel.filter(function(x){return typesFilter.indexOf(node.type(x)) == -1})

    // get nodes sorted by coordinates
    sel = sel.sort(function (b,a){return (node.coordY(a)*10000+node.coordX(a)) - (node.coordY(b)*10000+node.coordX(b))});

    if (sel.length==0) return;

    var homeGroup = node.parentNode(sel[0])
    var sceneComps = getSceneComposites(homeGroup);

    // prompt for a composite to connect to if there is more than  one
    if (sceneComps.length > 1){
        var compsNames = sceneComps.map(function(x){return node.getName(x)})
        var comp =  homeGroup+"/"+Input.getItem("Select a composite to link to:", compsNames);
    }else{
        var comp =  sceneComps[0]
    }

    // link the nodes to the comp
    for (var i in sel){
        MessageLog.trace("linking node "+sel[i]+" "+" to "+comp)
        node.link(sel[i], 0, comp, node.numberOfInputPorts(comp)+1)
    }

    scene.endUndoRedoAccum();

}


function disconnectAllSellNodes(){

    scene.beginUndoRedoAccum("disconnectAllSelNodes");

    var sel = selection.selectedNodes();
    for (var i in sel){
        for (var j=0; j<node.numberOfOutputPorts(sel[i]); j++){
            for (var k=0; k<node.numberOfOutputLinks(sel[i], j); j++){
                var dstNode = node.dstNode(sel[i], j, k)
                var port = getInputPort(sel[i], dstNode)
                if (port != -1) node.unlink(dstNode, port)
            }
        }
    }

    scene.endUndoRedoAccum();
}


function getSceneComposites(group){
    // returns a sorted list of all the composite Nodes in a group
    var nodes = node.subNodes(group).filter(function(x){return node.type(x) == "COMPOSITE"})
    return nodes.sort(function (a,b){return (node.coordY(a)*10000+node.coordX(a)) - (node.coordY(b)*10000+node.coordX(b))});
}


function getInputPort(srcNode, dstNode){
    // find the InPort through which two nodes are connected
    for (var i=0; i<node.numberOfInputPorts(dstNode); i++){
        var linkedNode = node.srcNode(dstNode, i);
        if (linkedNode == srcNode) return i;
    }
    return -1
}