From 6accc723974c403eec63ace45ebeaf6a535e95a9 Mon Sep 17 00:00:00 2001
From: Andrew Kingston <aptkingston@ssl-mail.com>
Date: Wed, 11 Aug 2021 15:07:06 +0100
Subject: [PATCH] Allow fields to dynamically update validation rules so that
 other fields can be referenced

---
 .../src/forms/Field.svelte                    |  5 +-
 .../src/forms/InnerForm.svelte                | 48 +++++++++++++++++--
 2 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/packages/standard-components/src/forms/Field.svelte b/packages/standard-components/src/forms/Field.svelte
index 61b2e41f09..e2c766a971 100644
--- a/packages/standard-components/src/forms/Field.svelte
+++ b/packages/standard-components/src/forms/Field.svelte
@@ -1,7 +1,7 @@
 <script>
   import Placeholder from "../Placeholder.svelte"
   import FieldGroupFallback from "./FieldGroupFallback.svelte"
-  import { getContext } from "svelte"
+  import { getContext, onMount } from "svelte"
 
   export let label
   export let field
@@ -34,6 +34,9 @@
   fieldApi = formField?.fieldApi
   fieldSchema = formField?.fieldSchema
 
+  // Keep validation rules up to date
+  $: fieldApi?.updateValidation(validation)
+
   // Extract label position from field group context
   $: labelPositionClass =
     labelPosition === "above" ? "" : `spectrum-FieldLabel--${labelPosition}`
diff --git a/packages/standard-components/src/forms/InnerForm.svelte b/packages/standard-components/src/forms/InnerForm.svelte
index 61b646e449..53208d2065 100644
--- a/packages/standard-components/src/forms/InnerForm.svelte
+++ b/packages/standard-components/src/forms/InnerForm.svelte
@@ -36,7 +36,7 @@
 
       // Create validation function based on field schema
       const schemaConstraints = schema?.[field]?.constraints
-      const validate = createValidatorFromConstraints(
+      const validator = createValidatorFromConstraints(
         schemaConstraints,
         validationRules,
         field,
@@ -47,10 +47,11 @@
       fieldMap[field] = {
         fieldState: makeFieldState(
           field,
+          validator,
           defaultValue,
           disabled || fieldDisabled || isAutoColumn
         ),
-        fieldApi: makeFieldApi(field, defaultValue, validate),
+        fieldApi: makeFieldApi(field, defaultValue),
         fieldSchema: schema?.[field] ?? {},
       }
 
@@ -93,9 +94,11 @@
   ]
 
   // Creates an API for a specific field
-  const makeFieldApi = (field, defaultValue, validate) => {
+  const makeFieldApi = field => {
+    // Sets the value for a certain field and invokes validation
     const setValue = (value, skipCheck = false) => {
       const { fieldState } = fieldMap[field]
+      const { defaultValue, validator } = get(fieldState)
 
       // Skip if the value is the same
       if (!skipCheck && get(fieldState).value === value) {
@@ -103,7 +106,7 @@
       }
 
       const newValue = value == null ? defaultValue : value
-      const newError = validate ? validate(newValue) : null
+      const newError = validator ? validator(newValue) : null
 
       // Update field state
       fieldState.update(state => {
@@ -127,15 +130,20 @@
       return !newError
     }
 
+    // Clears the value of a certain field back to the initial value
     const clearValue = () => {
       const { fieldState } = fieldMap[field]
+      const { defaultValue } = get(fieldState)
       const newValue = initialValues[field] ?? defaultValue
+
+      // Update field state
       fieldState.update(state => {
         state.value = newValue
         state.error = null
         return state
       })
 
+      // Update form state
       formState.update(state => {
         state.values = { ...state.values, [field]: newValue }
         delete state.errors[field]
@@ -144,9 +152,37 @@
       })
     }
 
+    // Updates the validator rules for a certain field
+    const updateValidation = validationRules => {
+      const { fieldState } = fieldMap[field]
+      const { value, error } = get(fieldState)
+
+      // Create new validator
+      const schemaConstraints = schema?.[field]?.constraints
+      const validator = createValidatorFromConstraints(
+        schemaConstraints,
+        validationRules,
+        field,
+        table
+      )
+
+      // Update validator
+      fieldState.update(state => {
+        state.validator = validator
+        return state
+      })
+
+      // If there is currently an error, run the validator again in case
+      // the error should be cleared by the new validation rules
+      if (error) {
+        setValue(value, true)
+      }
+    }
+
     return {
       setValue,
       clearValue,
+      updateValidation,
       validate: () => {
         const { fieldState } = fieldMap[field]
         setValue(get(fieldState).value, true)
@@ -155,13 +191,15 @@
   }
 
   // Creates observable state data about a specific field
-  const makeFieldState = (field, defaultValue, fieldDisabled) => {
+  const makeFieldState = (field, validator, defaultValue, fieldDisabled) => {
     return writable({
       field,
       fieldId: `id-${generateID()}`,
       value: initialValues[field] ?? defaultValue,
       error: null,
       disabled: fieldDisabled,
+      defaultValue,
+      validator,
     })
   }