private static void GoFindWay(SlingshotContext context, Node Start, Node End)
{
var queue = new List <Node>();
queue.Add(Start);
Start.Distance = 0;
do
{
queue.OrderBy(x => x.Distance).ToList();
var node = queue.First();
queue.Remove(node);
foreach (var connectedNode in node.GetConnections(context))
{
var childNode = connectedNode.Target;
if (childNode.Visited)
{
continue;
}
if (childNode.Distance == null || node.Distance + connectedNode.Cost < childNode.Distance)
{
childNode.Distance = node.Distance + connectedNode.Cost;
childNode.NearestToStart = node;
}
if (!queue.Contains(childNode))
{
queue.Add(childNode);
}
}
node.Visited = true;
if (node == End)
{
return;
}
} while (queue.Any());
}
private static void InsertDataIntoDatabase(SlingshotContext context, IList <Node> nodes, IList <Edge> edges)
{
foreach (var node in nodes)
{
if (context.Nodes.Where(n => n.Id == node.Id).FirstOrDefault() == null)
{
context.Nodes.Add(node);
}
}
foreach (var edge in edges)
{
if (context.Edges.Where(e => e.Id == edge.Id).FirstOrDefault() == null)
{
edge.Cost = edge.GetCost();
context.Edges.Add(edge);
}
}
try
{
context.SaveChanges();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
public static List <Node> GetShortestPathDijkstra(Node Start, Node End, SlingshotContext context)
{
GoFindWay(context, Start, End);
var shortestPath = new List <Node>();
shortestPath.Add(End);
BuildShortestPath(shortestPath, End);
shortestPath.Reverse();
return(shortestPath);
}
static void Main(string[] args)
{
var context = new SlingshotContext();
string json;
using (StreamReader r = new StreamReader("../../../BasicJSON.json"))
{
json = r.ReadToEnd();
}
var obj = JObject.Parse(json);
var nodes = GetAllNodes(obj);
var edges = GetAllEdges(obj, nodes);
if (nodes.Count > 0 && edges.Count > 0)
{
Console.WriteLine("Nodes and edges red from JSON file successefully!");
}
else
{
Console.WriteLine("Problem accured while reading JSON file. Nodes or edges empty!");
}
InsertDataIntoDatabase(context, nodes, edges);
Console.WriteLine("Please enter the ID of PointA:");
var idA = Console.ReadLine();
var nodeA = context.Nodes.Where(n => n.Id == idA).FirstOrDefault();
while (nodeA == null)
{
Console.WriteLine("Please enter the correct ID of PointA:");
idA = Console.ReadLine();
nodeA = context.Nodes.Where(n => n.Id == idA).FirstOrDefault();
}
Console.WriteLine("Please enter the ID of PointB:");
var idB = Console.ReadLine();
var nodeB = context.Nodes.Where(n => n.Id == idB).FirstOrDefault();
while (nodeB == null)
{
Console.WriteLine("Please enter the correct ID of PointB:");
idB = Console.ReadLine();
nodeB = context.Nodes.Where(n => n.Id == idB).FirstOrDefault();
}
var path = GetShortestPathDijkstra(nodeA, nodeB, context);
PrintPath(path);
Console.WriteLine("Press enter for finish!");
Console.ReadLine();
}
public IList <Edge> GetConnections(SlingshotContext context) => context.Edges.Where(s => s.Source == this).OrderBy(s => s.Cost).ToList();
