working examples 4 and 5

canvas/src/editor.rs

@@ -134,6 +134,24 @@ impl<D: DataProvider> FormEditor<D> {
         &self.ui_state
     }
 
+    /// Set external validation state for a field (Feature 5)
+    #[cfg(feature = "validation")]
+    pub fn set_external_validation(
+        &mut self,
+        field_index: usize,
+        state: crate::validation::ExternalValidationState,
+    ) {
+        self.ui_state
+            .validation
+            .set_external_validation(field_index, state);
+    }
+
+    /// Clear external validation state for a field (Feature 5)
+    #[cfg(feature = "validation")]
+    pub fn clear_external_validation(&mut self, field_index: usize) {
+        self.ui_state.validation.clear_external_validation(field_index);
+    }
+
     /// Get effective display text for any field index.
     ///
     /// Policies:

canvas/src/validation/config.rs

@@ -22,6 +22,9 @@ pub struct ValidationConfig {
     #[cfg(feature = "validation")]
     pub custom_formatter: Option<Arc<dyn CustomFormatter + Send + Sync>>,
 
+    /// Enable external validation indicator UI (feature 5)
+    pub external_validation_enabled: bool,
+
     /// Future: External validation
     pub external_validation: Option<()>, // Placeholder for future implementation
 }
@@ -47,6 +50,7 @@ impl std::fmt::Debug for ValidationConfig {
                   }
               },
           )
+          .field("external_validation_enabled", &self.external_validation_enabled)
           .field("external_validation", &self.external_validation)
           .finish()
     }
@@ -285,6 +289,12 @@ impl ValidationConfigBuilder {
         self
     }
 
+    /// Enable or disable external validation indicator UI (feature 5)
+    pub fn with_external_validation_enabled(mut self, enabled: bool) -> Self {
+        self.config.external_validation_enabled = enabled;
+        self
+    }
+
     /// Build the final validation configuration
     pub fn build(self) -> ValidationConfig {
         self.config

canvas/src/validation/mod.rs

@@ -16,6 +16,16 @@ pub use patterns::{PatternFilters, PositionFilter, PositionRange, CharacterFilte
 pub use mask::DisplayMask;  // Simple mask instead of ReservedCharacters
 pub use formatting::{CustomFormatter, FormattingResult, PositionMapper, DefaultPositionMapper};
 
+/// External validation UI state (Feature 5)
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ExternalValidationState {
+    NotValidated,
+    Validating,
+    Valid(Option<String>),
+    Invalid { message: String, suggestion: Option<String> },
+    Warning { message: String },
+}
+
 /// Validation error types
 #[derive(Debug, Clone, thiserror::Error)]
 pub enum ValidationError {

canvas/src/validation/state.rs

@@ -1,9 +1,7 @@
 // src/validation/state.rs
 //! Validation state management
 
-use crate::validation::{ValidationConfig, ValidationResult};
+use crate::validation::{ValidationConfig, ValidationResult, ExternalValidationState};
-#[cfg(feature = "validation")]
-use crate::validation::{PositionMapper};
 use std::collections::HashMap;
 
 /// Validation state for all fields in a form
@@ -20,6 +18,9 @@ pub struct ValidationState {
     
     /// Global validation enabled/disabled
     enabled: bool,
+
+    /// External validation results per field (Feature 5)
+    external_results: HashMap<usize, ExternalValidationState>,
 }
 
 impl ValidationState {
@@ -30,6 +31,7 @@ impl ValidationState {
             field_results: HashMap::new(),
             validated_fields: std::collections::HashSet::new(),
             enabled: true,
+            external_results: HashMap::new(),
         }
     }
     
@@ -40,6 +42,7 @@ impl ValidationState {
             // Clear all validation results when disabled
             self.field_results.clear();
             self.validated_fields.clear();
+            self.external_results.clear(); // Also clear external results
         }
     }
     
@@ -50,12 +53,13 @@ impl ValidationState {
     
     /// Set validation configuration for a field
     pub fn set_field_config(&mut self, field_index: usize, config: ValidationConfig) {
-        if config.has_validation() {
+        if config.has_validation() || config.external_validation_enabled {
             self.field_configs.insert(field_index, config);
         } else {
             self.field_configs.remove(&field_index);
             self.field_results.remove(&field_index);
             self.validated_fields.remove(&field_index);
+            self.external_results.remove(&field_index);
         }
     }
     
@@ -69,6 +73,30 @@ impl ValidationState {
         self.field_configs.remove(&field_index);
         self.field_results.remove(&field_index);
         self.validated_fields.remove(&field_index);
+        self.external_results.remove(&field_index);
+    }
+    
+    /// Set external validation state for a field (Feature 5)
+    pub fn set_external_validation(&mut self, field_index: usize, state: ExternalValidationState) {
+        self.external_results.insert(field_index, state);
+    }
+    
+    /// Get current external validation state for a field
+    pub fn get_external_validation(&self, field_index: usize) -> ExternalValidationState {
+        self.external_results
+            .get(&field_index)
+            .cloned()
+            .unwrap_or(ExternalValidationState::NotValidated)
+    }
+    
+    /// Clear external validation state for a field
+    pub fn clear_external_validation(&mut self, field_index: usize) {
+        self.external_results.remove(&field_index);
+    }
+    
+    /// Clear all external validation states
+    pub fn clear_all_external_validation(&mut self) {
+        self.external_results.clear();
     }
     
     /// Validate character insertion for a field
@@ -131,7 +159,7 @@ impl ValidationState {
         &self,
         field_index: usize,
         raw: &str,
-    ) -> Option<(String, std::sync::Arc<dyn PositionMapper>, Option<String>)> {
+    ) -> Option<(String, std::sync::Arc<dyn crate::validation::PositionMapper>, Option<String>)> {
         let config = self.field_configs.get(&field_index)?;
         config.run_custom_formatter(raw)
     }