3 files changed, 236 insertions, 0 deletions
diff --git a/src/ee/drawio.py b/src/ee/drawio.py
new file mode 100644
index 0000000..de98986
--- /dev/null
+++ b/src/ee/drawio.py
@@ -0,0 +1,187 @@
+import base64
+import urllib.parse
+import zlib
+from pathlib import Path
+from typing import Mapping, MutableMapping
+from xml.dom import minidom
+from lxml import etree
+
+
+def decompress(input_stream, output_stream):
+    doc = minidom.parse(input_stream)
+
+    diagram_elem = doc.getElementsByTagName("diagram")[0]
+
+    decompressor = zlib.decompressobj(-zlib.MAX_WBITS)
+    bs = base64.b64decode(diagram_elem.firstChild.wholeText)
+    inflated = decompressor.decompress(bs)
+    inflated += decompressor.flush()
+    xml = urllib.parse.unquote(bytes.decode(inflated, "ascii"))
+    doc = minidom.parseString(xml)
+    pretty_xml = doc.toprettyxml(indent="  ")
+    print(pretty_xml, file=output_stream)
+
+
+class GraphObject(object):
+    def __init__(self, id_: str, attrs, value):
+        self.id = id_
+        self.attrs = attrs
+        self.value = value
+        self.incoming: MutableMapping[str, "GraphEdge"] = {}
+        self.outgoing: MutableMapping[str, "GraphEdge"] = {}
+
+    def add_attr(self, key, value):
+        self.attrs[key] = value
+
+    def add_incoming(self, edge: "GraphEdge"):
+        self.incoming[edge.id] = edge
+
+    def add_outgoing(self, edge: "GraphEdge"):
+        self.outgoing[edge.id] = edge
+
+
+class GraphEdge(object):
+    def __init__(self, id_, attrs, source_id, target_id, value):
+        self.id = id_
+        self.attrs = attrs
+        self.source_id = source_id
+        self.target_id = target_id
+        self.value = value
+
+        self.source: GraphObject = None
+        self.target: GraphObject = None
+
+    def add_attr(self, key, value):
+        self.attrs[key] = value
+
+
+class GraphModel(object):
+    def __init__(self, objects: Mapping[str, GraphObject], edges: Mapping[str, GraphEdge]):
+        self.objects = objects
+        self.edges = edges
+
+    @staticmethod
+    def create(objects: Mapping[str, GraphObject], edges: Mapping[str, GraphEdge]) -> "GraphModel":
+        for id_, edge in edges.items():
+            source = objects[edge.source_id]
+            target = objects[edge.target_id]
+
+            source.add_outgoing(edge)
+            target.add_incoming(edge)
+
+            edge.source = source
+            edge.target = target
+
+        return GraphModel(objects, edges)
+
+
+def load_graph(doc) -> GraphModel:
+    def parse_text(s: str):
+        if s is None:
+            return None
+        return s.replace("<br>", "\n").strip()
+
+    root = doc.getroot()
+
+    objects = {}
+    edges = {}
+    root = root.find("root")
+    for child in root:
+        try:
+            a = child.attrib
+            id_ = child.attrib["id"]
+
+            value = None
+            attrs = {}
+            if child.tag == "mxCell":
+                value = a.get("value")
+                bad_keys = ("id", "edge", "parent", "vertex", "style", "source", "target", "value")
+                cell = child
+            elif child.tag == "object":
+                value = a.get("label")
+                cell = child.find("mxCell")
+                a = cell.attrib
+                bad_keys = ("id", "label", "placeholders")
+            else:
+                raise KeyError("Unknown tag: {}".format(child.tag))
+
+            attrs = {key: value for key, value in child.attrib.items() if key not in bad_keys}
+
+            value = parse_text(value)
+
+            vertex = "vertex" in a and a["vertex"] == "1"
+            edge = "edge" in a and a["edge"] == "1"
+
+            if (edge and vertex) or (not edge and not vertex):
+                continue  # don't know what these really are
+                # raise ValueError("node is neither edge nor vertex: {}".format(a["id"]))
+
+            if vertex:
+                objects[id_] = GraphObject(id_, attrs, value)
+            else:
+                source_id = a["source"]
+                target_id = a["target"]
+                edges[id_] = GraphEdge(id_, attrs, source_id, target_id, value)
+
+        except KeyError as e:
+            id_ = child.attrib["id"] if "id" in child.attrib else "unknown"
+            raise KeyError("Error while processing {}: {}, id={}".format(child, str(e), id_))
+
+    return GraphModel.create(objects, edges)
+
+
+def to_parts(in_path: Path, out_path: Path):
+    doc = etree.parse(str(in_path))
+    graph = load_graph(doc)
+
+
+def to_dot(in_path: Path, out_path: Path):
+    def to_id(s: str):
+        return s.replace("-", "_")
+
+    def quote(s: str):
+        return s.replace("\"", "\\\"")
+
+    doc = etree.parse(str(in_path))
+    graph = load_graph(doc)
+
+    print("digraph parts {")
+    for id_, obj in graph.objects.items():
+        if len(obj.attrs):
+            attr_str = "\\n".join(["{}={}".format(k, quote(v)) for k, v in obj.attrs.items()])
+            print("  {}_attrs [shape=plaintext, label=\"{}\"]".format(to_id(obj.id), quote(attr_str)))
+            print("  {}_attrs -> {} [arrowhead=none,style=dotted]".format(to_id(obj.id), to_id(obj.id)))
+
+        attrs = {}
+        if obj.value:
+            attrs["label"] = obj.value
+
+        attr_str = ",".join(["{}=\"{}\"".format(k, quote(v)) for k, v in attrs.items()])
+        print("  {} [{}];".format(to_id(obj.id), attr_str))
+
+    for id_, edge in graph.edges.items():
+        source_id = edge.source.id
+        target_id = edge.target.id
+
+        if len(edge.attrs):
+            print(" // source={}, target={}".format(source_id, target_id))
+            attr_str = "\\n".join(["{}={}".format(k, quote(v)) for k, v in edge.attrs.items()])
+
+            print("  {}_fake [shape=plaintext, label=\"{}\"]".format(to_id(edge.target.id), attr_str))
+            print("  {}_fake -> {}".format(to_id(edge.target.id), to_id(edge.target.id)))
+            # source_id = "{}_fake".format(to_id(edge.id))
+            target_id = "{}_fake".format(to_id(edge.target.id))
+            arrowhead="none"
+        else:
+            arrowhead="normal"
+
+        attrs = {}
+        # if edge.value:
+        #     attrs["label"] = edge.value
+
+        # attr_str = ",".join(["{}=\"{}\"".format(k, quote(v)) for k, v in attrs.items()])
+
+        print("  {} -> {}  [arrowhead={}];".format(to_id(source_id), to_id(target_id), arrowhead))
+        for k, v in edge.attrs.items():
+            print("  // {}={}".format(k, v))
+    print("}")
diff --git a/src/ee/tools/drawio-to-parts.py b/src/ee/tools/drawio-to-parts.py
new file mode 100644
index 0000000..562e341
--- /dev/null
+++ b/src/ee/tools/drawio-to-parts.py
@@ -0,0 +1,20 @@
+import argparse
+from pathlib import Path
+
+import ee.drawio
+
+parser = argparse.ArgumentParser()
+
+parser.add_argument("--in",
+                    dest="in_path",
+                    required=True,
+                    metavar="XML")
+
+parser.add_argument("--out",
+                    required=True,
+                    metavar="PART DB")
+
+args = parser.parse_args()
+
+# ee.drawio.to_parts(Path(args.in_path), Path(args.out))
+ee.drawio.to_dot(Path(args.in_path), Path(args.out))
diff --git a/src/ee/tools/drawio_decompress.py b/src/ee/tools/drawio_decompress.py
new file mode 100644
index 0000000..27e51af
--- /dev/null
+++ b/src/ee/tools/drawio_decompress.py
@@ -0,0 +1,29 @@
+import argparse
+import sys
+
+from ee.drawio import decompress
+
+parser = argparse.ArgumentParser()
+
+parser.add_argument("--in",
+                    dest="in_path",
+                    metavar="DRAWIO")
+
+parser.add_argument("--out",
+                    metavar="XML")
+
+args = parser.parse_args()
+
+in_stream = out_stream = None
+
+try:
+    in_stream = open(args.in_path, "rb") if args.in_path else sys.stdin
+    out_stream = open(args.out, "wr") if args.out else sys.stdout
+
+    decompress(in_stream, out_stream)
+except:
+    if in_stream:
+        in_stream.close()
+
+    if out_stream:
+        out_stream.close()