Added Usecases to assign, edit and unassign Lag Times to the ifcopenshell.api

src/ifcopenshell-python/ifcopenshell/api/sequence/assign_lag_time.py

@@ -0,0 +1,20 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {"rel_sequence": None, "lag_value": None, "duration_type": "NOTEDEFINED"}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        lag_value = self.file.createIfcDuration(self.settings["lag_value"])
+        lag_time = self.file.create_entity("IfcLagTime",
+            **{
+            "DurationType": self.settings["duration_type"],
+            "LagValue": lag_value,
+            }
+        )
+        #Can an IfcLagTime entity be used by multiple sequence relationships?
+        if self.settings["rel_sequence"].is_a("IfcRelSequence"):
+            if len(self.file.get_inverse(self.settings["rel_sequence"].TimeLag)) == 1:
+                self.file.remove(self.settings["rel_sequence"].TimeLag)
+        self.settings["rel_sequence"].TimeLag = lag_time

src/ifcopenshell-python/ifcopenshell/api/sequence/edit_lag_time.py

@@ -0,0 +1,13 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {"rel_sequence": None, "attributes": {}}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for name, value in self.settings["attributes"].items():
+            if name == "LagValue" and value is not None:
+                # TODO: support RatioMeasure
+                value = self.file.createIfcDuration(value)
+            setattr(self.settings["rel_sequence"], name, value)

src/ifcopenshell-python/ifcopenshell/api/sequence/edit_sequence.py

@@ -0,0 +1,10 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {"rel_sequence": None, "attributes": {}}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for name, value in self.settings["attributes"].items():
+            setattr(self.settings["rel_sequence"], name, value)

src/ifcopenshell-python/ifcopenshell/api/sequence/unassign_lag_time.py

@@ -0,0 +1,13 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "rel_sequence": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        if self.settings["rel_sequence"].TimeLag.LagValue:
+            self.file.remove(self.settings["rel_sequence"].TimeLag.LagValue)
+        self.file.remove(self.settings["rel_sequence"].TimeLag)