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djangorota/rota/forms.py

@@ -204,6 +204,120 @@ class RotaOptionsForm(forms.Form):
     )
 
 
+class RotaConstraintOptionsForm(forms.Form):
+    """Dynamically generated form exposing typed `RotaConstraintOptions` fields.
+
+    Fields are created as `opt__{key}` to match existing modal rendering logic
+    and to allow reuse of the `rota_options` endpoint/modal. Saving via
+    `save_for_rota(rota)` will update only the constraint keys inside
+    `RotaSchedule.options`, leaving other keys (e.g. legacy builder args)
+    untouched.
+    """
+
+    def __init__(self, *args, initial_options=None, **kwargs):
+        """initial_options: dict of existing rota.options to populate current values."""
+        super().__init__(*args, **kwargs)
+        initial_options = initial_options or {}
+
+        # Try to import the typed model from the rota package. Prefer the
+        # RotaConstraintOptions class (no heavy instantiation) to avoid any
+        # side-effects of creating a RotaBuilder instance during form init.
+        opts_model = None
+        try:
+            mod = importlib.import_module("rota_generator.shifts")
+            RotaConstraintOptions = getattr(mod, "RotaConstraintOptions", None)
+            if RotaConstraintOptions is not None:
+                opts_model = RotaConstraintOptions()
+            else:
+                # Last-resort: try to instantiate RotaBuilder and read its
+                # constraint_options_model attribute (may have side-effects).
+                RotaBuilder = getattr(mod, "RotaBuilder", None)
+                if RotaBuilder is not None:
+                    try:
+                        rb = RotaBuilder()
+                        opts_model = getattr(rb, "constraint_options_model", None)
+                    except Exception:
+                        opts_model = None
+        except Exception:
+            opts_model = None
+
+        self._constraint_defaults = {}
+        self._constraint_meta = {}
+
+        if opts_model is not None:
+            try:
+                defaults = opts_model.model_dump()
+            except Exception:
+                defaults = {}
+            self._constraint_defaults = defaults
+            # try to read field descriptions
+            try:
+                mf = opts_model.__class__.model_fields
+            except Exception:
+                mf = {}
+
+            for k, v in defaults.items():
+                field_name = f"opt__{k}"
+                help_text = None
+                if isinstance(mf, dict) and k in mf:
+                    info = mf[k]
+                    try:
+                        if hasattr(info, "description") and info.description:
+                            help_text = info.description
+                        else:
+                            help_text = info.get("description")
+                    except Exception:
+                        help_text = None
+
+                initial = initial_options.get(k, v)
+
+                # Map Python types to Django form fields
+                if isinstance(v, bool):
+                    self.fields[field_name] = forms.BooleanField(required=False, initial=bool(initial), label=k.replace("_", " "), help_text=help_text)
+                elif isinstance(v, int):
+                    # Allow None for Optional[int]
+                    self.fields[field_name] = forms.IntegerField(required=False, initial=initial, label=k.replace("_", " "), help_text=help_text)
+                elif isinstance(v, float):
+                    self.fields[field_name] = forms.FloatField(required=False, initial=initial, label=k.replace("_", " "), help_text=help_text)
+                elif isinstance(v, (list, dict)):
+                    # JSON textarea for structured values
+                    try:
+                        init_val = json.dumps(initial) if initial is not None else json.dumps(v)
+                    except Exception:
+                        init_val = ""
+                    self.fields[field_name] = forms.CharField(required=False, initial=init_val, widget=forms.Textarea, label=k.replace("_", " "), help_text=(help_text or "Enter JSON"))
+                else:
+                    self.fields[field_name] = forms.CharField(required=False, initial=initial if initial is not None else v, label=k.replace("_", " "), help_text=help_text)
+
+    def save_for_rota(self, rota):
+        """Persist cleaned constraint fields into `rota.options`.
+
+        Only updates keys that are present in the typed constraint defaults.
+        For structured fields (JSON), attempt to parse into Python objects.
+        """
+        opts = rota.options or {}
+        for key in self._constraint_defaults.keys():
+            field_name = f"opt__{key}"
+            if field_name in self.cleaned_data:
+                val = self.cleaned_data[field_name]
+                default = self._constraint_defaults.get(key)
+                if isinstance(default, (list, dict)):
+                    try:
+                        parsed = json.loads(val) if val is not None and val != "" else []
+                    except Exception:
+                        parsed = val
+                    opts[key] = parsed
+                else:
+                    # For optional int/float fields allow empty -> None
+                    if val == "" or val is None:
+                        opts[key] = None
+                    else:
+                        opts[key] = val
+
+        rota.options = opts
+        rota.save(update_fields=["options"]) 
+
+
 class ShiftForm(forms.Form):
     name = forms.CharField(max_length=200)
     sites = forms.CharField(