From 837cb4ce63142341086b7f1cb628674bb4c40544 Mon Sep 17 00:00:00 2001
From: Dominic Kempf <dominic.kempf@iwr.uni-heidelberg.de>
Date: Thu, 24 Feb 2022 18:16:40 +0100
Subject: [PATCH 1/2] Implement onesided minimum/maximum rules

---
 ipywidgets_jsonschema/form.py              | 33 ++++++++++++++++++++--
 tests/schemas/integer-onesided-max.json    | 12 ++++++++
 tests/schemas/integer-onesided-min.json    | 12 ++++++++
 tests/schemas/number-onesided-maximum.json | 12 ++++++++
 tests/schemas/number-onesided-min.json     | 12 ++++++++
 5 files changed, 79 insertions(+), 2 deletions(-)
 create mode 100644 tests/schemas/integer-onesided-max.json
 create mode 100644 tests/schemas/integer-onesided-min.json
 create mode 100644 tests/schemas/number-onesided-maximum.json
 create mode 100644 tests/schemas/number-onesided-min.json

diff --git a/ipywidgets_jsonschema/form.py b/ipywidgets_jsonschema/form.py
index 0c29bda..e5502c2 100644
--- a/ipywidgets_jsonschema/form.py
+++ b/ipywidgets_jsonschema/form.py
@@ -25,6 +25,33 @@ def as_tuple(obj):
         return (obj,)
 
 
+def minmax_schema_rule(widget, schema):
+    """This implements the minimum/maximum rules
+
+    Only used for inputs bounded from one side, as ipywidgets
+    has dedicated widgets for inputs bound from both sides. Defined
+    in a separate function, because it used twice for number and
+    integer widgets.
+    """
+    if "minimum" in schema:
+
+        def min_handler(_):
+            if widget.value < schema["minimum"]:
+                widget.value = schema["minimum"]
+
+        widget.observe(min_handler, names="value")
+
+    if "maximum" in schema:
+
+        def max_handler(_):
+            if widget.value > schema["maximum"]:
+                widget.value = schema["maximum"]
+
+        widget.observe(max_handler, names="value")
+
+    return widget
+
+
 class Form:
     def __init__(
         self,
@@ -297,7 +324,8 @@ def _construct_number(self, schema, label=None, root=False):
                 label=label,
             )
         else:
-            return self._construct_simple(schema, ipywidgets.FloatText(), label=label)
+            widget = minmax_schema_rule(ipywidgets.FloatText(), schema)
+            return self._construct_simple(schema, widget, label=label)
 
     def _construct_integer(self, schema, label=None, root=False):
         # Inputs bounded only from below or above are currently not supported
@@ -312,7 +340,8 @@ def _construct_integer(self, schema, label=None, root=False):
                 label=label,
             )
         else:
-            return self._construct_simple(schema, ipywidgets.IntText(), label=label)
+            widget = minmax_schema_rule(ipywidgets.IntText(), schema)
+            return self._construct_simple(schema, widget, label=label)
 
     def _construct_boolean(self, schema, label=None, root=False):
         # Extract the labelling for the checkbox
diff --git a/tests/schemas/integer-onesided-max.json b/tests/schemas/integer-onesided-max.json
new file mode 100644
index 0000000..5a37fa8
--- /dev/null
+++ b/tests/schemas/integer-onesided-max.json
@@ -0,0 +1,12 @@
+{
+  "default": 42,
+  "schema": {
+    "default": 42,
+    "maximum": 45,
+    "type": "integer"
+  },
+  "valid": [
+    45,
+    42
+  ]
+}
diff --git a/tests/schemas/integer-onesided-min.json b/tests/schemas/integer-onesided-min.json
new file mode 100644
index 0000000..c3cb839
--- /dev/null
+++ b/tests/schemas/integer-onesided-min.json
@@ -0,0 +1,12 @@
+{
+  "default": 42,
+  "schema": {
+    "default": 42,
+    "minimum": 40,
+    "type": "integer"
+  },
+  "valid": [
+    40,
+    45
+  ]
+}
diff --git a/tests/schemas/number-onesided-maximum.json b/tests/schemas/number-onesided-maximum.json
new file mode 100644
index 0000000..238f887
--- /dev/null
+++ b/tests/schemas/number-onesided-maximum.json
@@ -0,0 +1,12 @@
+{
+  "default": 42,
+  "schema": {
+    "default": 42,
+    "maximum": 45,
+    "type": "number"
+  },
+  "valid": [
+    45,
+    42
+  ]
+}
diff --git a/tests/schemas/number-onesided-min.json b/tests/schemas/number-onesided-min.json
new file mode 100644
index 0000000..bb83793
--- /dev/null
+++ b/tests/schemas/number-onesided-min.json
@@ -0,0 +1,12 @@
+{
+  "default": 42,
+  "schema": {
+    "default": 42,
+    "minimum": 40,
+    "type": "number"
+  },
+  "valid": [
+    40,
+    45
+  ]
+}

From 5521c7111eb24a75a1efe89959964bc4819134ec Mon Sep 17 00:00:00 2001
From: Dominic Kempf <dominic.kempf@iwr.uni-heidelberg.de>
Date: Thu, 24 Feb 2022 19:17:07 +0100
Subject: [PATCH 2/2] Ensure that a valid value is used in absence of default
 value

---
 ipywidgets_jsonschema/form.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/ipywidgets_jsonschema/form.py b/ipywidgets_jsonschema/form.py
index e5502c2..34bfda6 100644
--- a/ipywidgets_jsonschema/form.py
+++ b/ipywidgets_jsonschema/form.py
@@ -254,6 +254,11 @@ def _construct_simple(self, schema, widget, label=None, root=False):
         # Apply a potential default
         if "default" in schema:
             widget.value = schema["default"]
+        else:
+            if "minimum" in schema:
+                widget.value = schema["minimum"]
+            if "maximum" in schema:
+                widget.value = schema["maximum"]
 
         # Apply potential constant values without generating a widget
         if "const" in schema: