function centerOn(nodeid) {
    if (!Mconsole.busy) {
        var node = Mconsole.graph.getNode(nodeid);
        $('div.index img').attr('src', imgArray[node.getData('metacode')].src);
        $('div.index .mapName').html(node.name);
        $(document).attr('title', node.name + ' | Metamaps');
        window.history.pushState(node.name, "Metamaps", "/topics/" + node.id);
        Mconsole.onClick(node.id, {
            hideLabels: false,
            duration: 1000,
            onComplete: function () {
                fetchRelatives(node);
            }
        });
    }
}

function editEdge(edge, e) {
    //reset so we don't interfere with other edges, but first, save its x and y 
    var myX = $('#edit_synapse').css('left');
    var myY = $('#edit_synapse').css('top');
    $('#edit_synapse').remove();

    //so label is missing while editing
    deselectEdge(edge);

    //create the wrapper around the form elements, including permissions
    //classes to make best_in_place happy
    var edit_div = document.createElement('div');
    edit_div.setAttribute('id', 'edit_synapse');
    if (authorizeToEdit(edge)) {
        edit_div.className = 'permission canEdit';
        edit_div.className += edge.getData('userid') === userid ? ' yourEdge' : '';
    } else {
        edit_div.className = 'permission cannotEdit';
    }
    $('.main .wrapper').append(edit_div);

    populateEditEdgeForm(edge);

    //drop it in the right spot, activate it
    $('#edit_synapse').css('position', 'absolute');
    if (e) {
        $('#edit_synapse').css('left', e.clientX);
        $('#edit_synapse').css('top', e.clientY);
    } else {
        $('#edit_synapse').css('left', myX);
        $('#edit_synapse').css('top', myY);
    }
    //$('#edit_synapse_name').click(); //required in case name is empty
    //$('#edit_synapse_name input').focus();
    $('#edit_synapse').show();

    MetamapsModel.edgecardInUse = edge.data.$id;
}

function populateEditEdgeForm(edge) {
    add_name_form(edge);
    add_user_info(edge);
    add_perms_form(edge);
    if (authorizeToEdit(edge)) {
        add_direction_form(edge);
    }
}

function add_name_form(edge) {
    var data_nil = '<span class="gray">Click to add description.</span>';
    //name editing form
    $('#edit_synapse').append('<div id="edit_synapse_name"></div>');
    $('#edit_synapse_name').attr('class', 'best_in_place best_in_place_desc');
    $('#edit_synapse_name').attr('data-object', 'synapse');
    $('#edit_synapse_name').attr('data-attribute', 'desc');
    $('#edit_synapse_name').attr('data-type', 'textarea');
    $('#edit_synapse_name').attr('data-nil', data_nil);
    $('#edit_synapse_name').attr('data-url', '/synapses/' + edge.getData("id"));
    $('#edit_synapse_name').html(edge.getData("desc"));

    //if edge data is blank or just whitespace, populate it with data_nil
    if ($('#edit_synapse_name').html().trim() == '') {
        $('#edit_synapse_name').html(data_nil);
    }

    $('#edit_synapse_name').bind("ajax:success", function () {
        var desc = $(this).html();
        if (desc == data_nil) {
            edge.setData("desc", '');
        } else {
            edge.setData("desc", desc);
        }
        selectEdge(edge);
        Mconsole.plot();
    });
}

function add_user_info(edge) {
    $('#edit_synapse').append('<div id="edgeUser" class="hoverForTip"><div class="tip">Created by ' + edge.getData("username") + '</div></div>');
}

function add_perms_form(edge) {
    //permissions - if owner, also allow permission editing
    $('#edit_synapse').append('<div class="mapPerm ' + mk_permission(edge) + '"></div>');

    // ability to change permission
    var selectingPermission = false;
    if (userid == edge.getData('userid')) {
        $('#edit_synapse.yourEdge .mapPerm').click(function () {
            if (!selectingPermission) {
                selectingPermission = true;
                $(this).addClass('minimize'); // this line flips the drop down arrow to a pull up arrow
                if ($(this).hasClass('co')) {
                    $(this).append('<ul class="permissionSelect"><li class="public"></li><li class="private"></li></ul>');
                } else if ($(this).hasClass('pu')) {
                    $(this).append('<ul class="permissionSelect"><li class="commons"></li><li class="private"></li></ul>');
                } else if ($(this).hasClass('pr')) {
                    $(this).append('<ul class="permissionSelect"><li class="commons"></li><li class="public"></li></ul>');
                }
                $('#edit_synapse .permissionSelect li').click(function (event) {
                    selectingPermission = false;
                    var permission = $(this).attr('class');
                    updateSynapsePermission(edge, permission);
                    event.stopPropagation();
                });
            } else {
                selectingPermission = false;
                $(this).removeClass('minimize'); // this line flips the pull up arrow to a drop down arrow
                $('#edit_synapse .permissionSelect').remove();
            }
        });
    }
} //add_perms_form

function add_direction_form(edge) {
    //directionality checkboxes
    $('#edit_synapse').append('<input type="checkbox" id="edit_synapse_left">');
    $('#edit_synapse').append('<label class="left">&lt;</label>');
    $('#edit_synapse').append('<input type="checkbox" id="edit_synapse_right">');
    $('#edit_synapse').append('<label class="right">&gt;</label>');

    //determine which node is to the left and the right
    //if directly in a line, top is left
    if (edge.nodeFrom.pos.x < edge.nodeTo.pos.x ||
        edge.nodeFrom.pos.x == edge.nodeTo.pos.x &&
        edge.nodeFrom.pos.y < edge.nodeTo.pos.y) {
        var left = edge.nodeTo;
        var right = edge.nodeFrom;
    } else {
        var left = edge.nodeFrom;
        var right = edge.nodeTo;
    }

    /*
     * One node is actually on the left onscreen. Call it left, & the other right.
     * If category is from-to, and that node is first, check the 'right' checkbox.
     * Else check the 'left' checkbox since the arrow is incoming.
     */

    var directionCat = edge.getData('category'); //both, none, from-to
    if (directionCat == 'from-to') {
        var from_to = edge.getData('direction');
        if (from_to[0] == left.id) {
            //check left checkbox
            $('#edit_synapse_left').prop('checked', true);
        } else {
            //check right checkbox
            $('#edit_synapse_right').prop('checked', true);
        }
    } else if (directionCat == 'both') {
        //check both checkboxes
        $('#edit_synapse_left').prop('checked', true);
        $('#edit_synapse_right').prop('checked', true);
    }
    $('#edit_synapse_left, #edit_synapse_right').click(function () {
        var leftChecked = $('#edit_synapse_left').is(':checked');
        var rightChecked = $('#edit_synapse_right').is(':checked');

        var dir = edge.getData('direction');
        var dirCat = 'none';
        if (leftChecked && rightChecked) {
            dirCat = 'both';
        } else if (!leftChecked && rightChecked) {
            dirCat = 'from-to';
            dir = [right.id, left.id];
        } else if (leftChecked && !rightChecked) {
            dirCat = 'from-to';
            dir = [left.id, right.id];
        }
        $.ajax({
            'type': 'PUT',
            'url': '/synapses/' + edge.getData('id'),
            'data': {
                synapse: {
                    category: dirCat
                },
                node1_id: {
                    node1: dir[0]
                },
                node2_id: {
                    node2: dir[1]
                }
            },
            'success': function (data) {
                updateEdgeDisplay(edge, dir, dirCat);
            }
        });
    });
} //add_direction_form

function updateEdgeDisplay(edge, dir, dirCat) {
    edge.setData('category', dirCat);
    edge.setData('direction', dir);

    //render mid arrow
    //renderEdgeArrows(Mconsole.fx.edgeHelper, edge);
    Mconsole.plot();
}

function deselectAllEdges() {
    var l = MetamapsModel.selectedEdges.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var edge = MetamapsModel.selectedEdges[i];
        deselectEdge(edge);
    }
}

function deselectAllNodes() {
    var l = MetamapsModel.selectedNodes.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var node = MetamapsModel.selectedNodes[i];
        deselectNode(node);
    }
}

// this is for hiding one topic from your canvas
function removeEdge(edge) {
    var id = edge.getData("id");
    $.ajax({
        type: "DELETE",
        url: "/synapses/" + id,
        success: function () {
            hideEdge(edge);
        },
    });
}

function hideEdge(edge) {
    var from = edge.nodeFrom.id;
    var to = edge.nodeTo.id;
    edge.setData('alpha', 0, 'end');
    Mconsole.fx.animate({
        modes: ['edge-property:alpha'],
        duration: 1000
    });
    Mconsole.graph.removeAdjacence(from, to);
    Mconsole.plot();
}

function hideSelectedEdges() {
    var l = MetamapsModel.selectedEdges.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var edge = MetamapsModel.selectedEdges[i];
        hideEdge(edge);
    }
    MetamapsModel.selectedEdges = new Array();
}

function removeSelectedEdges() {
    var l = MetamapsModel.selectedEdges.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        if (mapid != null) {
            var edge = MetamapsModel.selectedEdges[i];
            var id = edge.getData("id");
            //delete mapping of id mapid
            $.ajax({
                type: "POST",
                url: "/synapses/" + mapid + "/" + id + "/removefrommap",
            });
        }
        hideEdge(edge);
    }
    MetamapsModel.selectedEdges = new Array();
}

function deleteSelectedEdges() {
    var l = MetamapsModel.selectedEdges.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var edge = MetamapsModel.selectedEdges[i];
        var id = edge.getData("id");
        $.ajax({
            type: "DELETE",
            url: "/synapses/" + id,
        });
        hideEdge(edge);
    }
    MetamapsModel.selectedEdges = new Array();
}

function selectNode(node) {
    if (MetamapsModel.selectedNodes.indexOf(node) != -1) return;
    node.selected = true;
    node.setData('dim', 30, 'current');
    node.setData('whiteCircle', true);
    node.eachAdjacency(function (adj) {
        selectEdge(adj);
    });
    MetamapsModel.selectedNodes.push(node);
}

function deselectNode(node) {
    delete node.selected;
    node.setData('whiteCircle', false);
    node.eachAdjacency(function (adj) {
        deselectEdge(adj);
    });
    node.setData('dim', 25, 'current');

    //remove the node
    MetamapsModel.selectedNodes.splice(
        MetamapsModel.selectedNodes.indexOf(node), 1);
}

function selectEdge(edge) {
    if (MetamapsModel.selectedEdges.indexOf(edge) != -1) return;
    edge.setData('showDesc', true, 'current');
    if (!MetamapsModel.embed) {
        edge.setDataset('end', {
            lineWidth: 4,
            color: '#FFFFFF',
            alpha: 1
        });
    } else if (MetamapsModel.embed) {
        edge.setDataset('end', {
            lineWidth: 4,
            color: '#999',
            alpha: 1
        });
    }
    Mconsole.fx.animate({
        modes: ['edge-property:lineWidth:color:alpha'],
        duration: 100
    });
    MetamapsModel.selectedEdges.push(edge);
}

function deselectEdge(edge) {
    edge.setData('showDesc', false, 'current');
    edge.setDataset('end', {
        lineWidth: 2,
        color: '#222222',
        alpha: 0.4
    });

    if (MetamapsModel.edgeHoveringOver == edge) {
        edge.setData('showDesc', true, 'current');
        edge.setDataset('end', {
            lineWidth: 4,
            color: '#222222',
            alpha: 1
        });
    }

    Mconsole.fx.animate({
        modes: ['edge-property:lineWidth:color:alpha'],
        duration: 100
    });

    //remove the edge
    MetamapsModel.selectedEdges.splice(
        MetamapsModel.selectedEdges.indexOf(edge), 1);
}

// this is for hiding one topic from your canvas
function hideNode(nodeid) {
    var node = Mconsole.graph.getNode(nodeid);
    if (nodeid == Mconsole.root && gType == "centered") {
        alert("You can't hide this topic, it is the root of your graph.");
        return;
    }

    deselectNode(node);

    node.setData('alpha', 0, 'end');
    node.eachAdjacency(function (adj) {
        adj.setData('alpha', 0, 'end');
    });
    Mconsole.fx.animate({
        modes: ['node-property:alpha',
   'edge-property:alpha'],
        duration: 1000
    });
    Mconsole.graph.removeNode(nodeid);
}

function hideSelectedNodes() {
    var l = MetamapsModel.selectedNodes.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var node = MetamapsModel.selectedNodes[i];
        hideNode(node.id);
    }
}

function removeNode(nodeid) {
    var node = Mconsole.graph.getNode(nodeid);
    deselectNode(node);
    if (mapperm) {
        $.ajax({
            type: "POST",
            url: "/topics/" + mapid + "/" + nodeid + "/removefrommap",
        });
    }
}

function removeSelectedNodes() {
    if (mapperm) {
        var l = MetamapsModel.selectedNodes.length;
        for (var i = l - 1; i >= 0; i -= 1) {
            var node = MetamapsModel.selectedNodes[i];
            removeNode(node.id);
        }
    }
}

function deleteNode(nodeid) {
    if (nodeid == Mconsole.root && gType == "centered") {
        alert("You can't delete this topic, it is the root of your graph.");
        return;
    }
    $.ajax({
        type: "DELETE",
        url: "/topics/" + nodeid,
    });
}

function deleteSelectedNodes() {
    var l = MetamapsModel.selectedNodes.length;
    for (var i = l - 1; i >= 0; i -= 1) {
        var node = MetamapsModel.selectedNodes[i];
        deleteNode(node.id);
    }
}