kabellaengen/lib/routing.py

import os
import json
import argparse
import heapq
import math
import matplotlib.pyplot as plt
import networkx as nx

# Hilfsfunktionen
def load_json(filepath):
    with open(filepath, 'r', encoding='utf-8') as f:
        return json.load(f)

def parse_pos(pos_str):
    """ Konvertiert '(x, y)' oder '(x, y, z)' in ein Tuple """
    try:
        return tuple(map(float, pos_str.strip('[]').split(',')))
    except Exception:
        raise ValueError(f"Ungültiges Positionsformat: {pos_str}")

def distance(p1, p2):
    """ Euklidische Distanz in 2D """
    return math.sqrt((p1[0] - p2[0])**2 + (p1[1] - p2[1])**2)

def add_edge(graph, node1, node2, dist):
    """ Fügt eine ungerichtete Kante zwischen zwei Knoten hinzu, aber nur einmal """
    if node1 not in graph:
        graph[node1] = []
    if node2 not in graph:
        graph[node2] = []

    # Nur hinzufügen, wenn Kante noch nicht existiert (ungerichtet)
    if not any(n == node2 for n, _ in graph[node1]):
        graph[node1].append((node2, dist))
    if not any(n == node1 for n, _ in graph[node2]):
        graph[node2].append((node1, dist))

def project_point_on_segment(p, a, b):
    """ Projektion eines Punktes p auf ein Liniensegment a-b """
    ax, ay = a
    bx, by = b
    px, py = p

    dx = bx - ax
    dy = by - ay
    if dx == dy == 0:
        return a

    t = ((px - ax) * dx + (py - ay) * dy) / (dx * dx + dy * dy)
    t = max(0, min(1, t))  # Begrenze t auf [0,1]
    return (ax + t * dx, ay + t * dy)

def dijkstra(graph, start):
    """ Dijkstra-Algorithmus, um die kürzesten Wege im Graphen zu berechnen """
    distances = {node: float('inf') for node in graph}
    distances[start] = 0
    priority_queue = [(0, start)]  # (Distanz, Knoten)
    
    while priority_queue:
        current_distance, current_node = heapq.heappop(priority_queue)

        if current_distance > distances[current_node]:
            continue

        for neighbor, weight in graph[current_node]:
            distance = current_distance + weight

            if distance < distances[neighbor]:
                distances[neighbor] = distance
                heapq.heappush(priority_queue, (distance, neighbor))

    return distances

def print_graph(graph):
    printed = set()
    for node, edges in graph.items():
        for neighbor, dist in edges:
            edge_id = tuple(sorted((node, neighbor)))
            if edge_id not in printed:
                printed.add(edge_id)
                print(f"{edge_id[0]} --> {edge_id[1]} (Distanz: {dist})")


def visualize_graph(graph, racks):
    G = nx.Graph()
    pos = {}

    for node, edges in graph.items():
        pos[node] = node_to_coords(node, racks)
        for neighbor, distance in edges:
            if not G.has_edge(node, neighbor):  # Doppelte Kanten vermeiden
                G.add_edge(node, neighbor, weight=round(distance, 1))

    plt.figure(figsize=(10, 10))
    nx.draw(
        G, pos,
        with_labels=True,
        node_size=100,
        font_size=8,
        node_color='skyblue',
        edge_color='gray'
    )

    edge_labels = nx.get_edge_attributes(G, 'weight')
    nx.draw_networkx_edge_labels(G, pos, edge_labels=edge_labels, font_size=6)

    plt.title("Rack-Graph (aus racks.json)")
    plt.axis("equal")
    plt.tight_layout()
    plt.show()


def node_to_coords(node_name, racks):
    """Extrahiert die Koordinaten aus dem Knotennamen wie 'Rack_1_Node_2'"""
    parts = node_name.split("_")
    rack = f"{parts[0]}_{parts[1]}"
    node = f"{parts[2]}_{parts[3]}"
    coords = racks[rack][node]
    return tuple(coords)



if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='Berechne Wege von Sensoren zu Verteilern über Kabeltrassen')
    parser.add_argument('-i', '--inputfile', action='store', required=True, default="easy_position.json", help='file with all informations about positions gathered from getpositions', metavar='my_positions.json')
    parser.add_argument('-c', '--console', action='store_true', help='Ausgabe auf Konsole')

    args = parser.parse_args()

    # Umgebungsvariablen
    work_dir = os.environ.get("PROJECT_WORK")
    config_dir = os.environ.get("PROJECT_CFG")

    # Pfade zu JSON-Dateien
    jsonfilename = args.inputfile
    sensors_path = os.path.join(work_dir, jsonfilename)

    # Einlesen
    
    data = load_json(sensors_path)
    sensors = data["sensors"]
    subdists = data["distributors"]
    racks = data["racks"]

    # Graph erstellen
    graph = {}

    for rack_id, rack in racks.items():
        nodes = list(rack.values())  # Liste aller Knoten im Rack

        for i in range(len(nodes) - 1):
            segment_start = tuple(nodes[i])
            segment_end = tuple(nodes[i + 1])
            dist = distance(segment_start, segment_end)

            # Erstelle Kanten zwischen den benachbarten Knoten
            add_edge(graph, f"{rack_id}_Node_{i+1}", f"{rack_id}_Node_{i+2}", dist)

    # Graph in Kommandozeile beschreiben und mittels matplotlib ausgeben
    print("\nGraph basierend auf den Racks (ungerichtet, eindeutige Kanten):")
    print_graph(graph)

    visualize_graph(graph, racks)



    """# 1. Vom Sensor zum Rack laufen und Knoten einfügen
    for sensor_id, sensor_info in sensors.items():
        sensor_pos = tuple(sensor_info['pos'])
        for rack in racks:
            for segment_start, segment_end in zip(rack[:-1], rack[1:]):
                # Berechne Distanz von Sensor zur Kabeltrasse
                px, py = project_point_on_segment(sensor_pos, segment_start, segment_end)
                dist = distance(sensor_pos, (px, py))
                rack_id = f"rack_{rack}"
                # Sensor zum Rack Knoten verbinden
                add_edge(graph, sensor_id, rack_id, dist)

    # 2. Vom Unterverteiler (UV) zum Rack laufen und Knoten einfügen
    for uc_id, uc_pos in subdists.items():
        for rack in racks:
            for segment_start, segment_end in zip(rack[:-1], rack[1:]):
                # Berechne Distanz von UV zur Kabeltrasse
                px, py = project_point_on_segment(uc_pos, segment_start, segment_end)
                dist = distance(uc_pos, (px, py))
                rack_id = f"rack_{rack}"
                # UV zum Rack Knoten verbinden
                add_edge(graph, uc_id, rack_id, dist)

    # 3. Vom Sensor Knoten zum zugehörigen Unterverteiler Knoten entlang der Racks
    for sensor_id, sensor_info in sensors.items():
        subdist_id = None
        if 'KENNZEICHNUNG' in sensor_info:
            for uc_id in subdists:
                if uc_id in sensor_info['KENNZEICHNUNG']:
                    subdist_id = uc_id
                    break
        if subdist_id:
            # Verbinde den Sensor mit dem zugehörigen Unterverteiler
            sensor_pos = tuple(sensor_info['pos'])
            uc_pos = subdists[subdist_id]
            # Berechne Distanz von Sensor zum Unterverteiler (über Trassen)
            dist = distance(sensor_pos, uc_pos)
            add_edge(graph, sensor_id, subdist_id, dist)

    # 4. Berechnung der kürzesten Wege mit Dijkstra
    routing_result = {}
    for sensor_id in sensors:
        distances = dijkstra(graph, sensor_id)
        routing_result[sensor_id] = distances

    if args.console:
        print(json.dumps(routing_result, indent=2))"""