#!/usr/bin/env python3
#
# Produces a complete database of wires in the ROI and their connections and tests if each
# routing node is a tree (i.e. fails with an error when a loop is found).

import os, sys, json

with open("%s/%s/tilegrid.json" % (os.getenv("XRAY_DATABASE_DIR"),
                                   os.getenv("XRAY_DATABASE")), "r") as f:
    tilegrid = json.load(f)["tiles"]

with open("%s/%s/tileconn.json" % (os.getenv("XRAY_DATABASE_DIR"),
                                   os.getenv("XRAY_DATABASE")), "r") as f:
    tileconn = json.load(f)

grid = dict()
wirepairs = dict()
remwires = set()

for tilename, tiledata in tilegrid.items():
    key = (tiledata["grid_x"], tiledata["grid_y"])
    grid[key] = tilename


def check_tileconn_entry(tilename, tiledata, entry, idx):
    if idx == 0:
        otheridx = 1
        otherxy = (
            tiledata["grid_x"] + entry["grid_deltas"][0],
            tiledata["grid_y"] + entry["grid_deltas"][1])
    else:
        otheridx = 0
        otherxy = (
            tiledata["grid_x"] - entry["grid_deltas"][0],
            tiledata["grid_y"] - entry["grid_deltas"][1])

    if otherxy not in grid:
        return

    othertilename = grid[otherxy]
    othertiledata = tilegrid[othertilename]

    if othertiledata["type"] != entry["tile_types"][otheridx]:
        return

    print(
        "  Found relevant entry (%s %s %d %d): %s" % (
            entry["tile_types"][0], entry["tile_types"][1],
            entry["grid_deltas"][0], entry["grid_deltas"][1], othertilename))

    for pair in entry["wire_pairs"]:
        wirename = "%s/%s" % (tilename, pair[idx])
        otherwirename = "%s/%s" % (othertilename, pair[otheridx])

        remwires.add(wirename)
        remwires.add(otherwirename)

        if wirename not in wirepairs:
            wirepairs[wirename] = set()
        wirepairs[wirename].add(otherwirename)

        if otherwirename not in wirepairs:
            wirepairs[otherwirename] = set()
        wirepairs[otherwirename].add(wirename)


for tilename, tiledata in tilegrid.items():
    print("Connecting wires in tile %s." % tilename)
    for entry in tileconn:
        if entry["tile_types"][0] == tiledata["type"]:
            check_tileconn_entry(tilename, tiledata, entry, 0)
        if entry["tile_types"][1] == tiledata["type"]:
            check_tileconn_entry(tilename, tiledata, entry, 1)


def check_wire(wire, source):
    for next_wire in wirepairs[wire]:
        if next_wire == source:
            continue
        print("  %s" % next_wire)
        if next_wire not in remwires:
            print("  ** FOUND LOOP IN THIS NODE **")
            sys.exit(1)
        remwires.remove(next_wire)
        check_wire(next_wire, wire)


while len(remwires):
    wire = remwires.pop()
    print("Checking %s:" % wire)
    check_wire(wire, None)

print("NO LOOP FOUND: OK")