validation1 for the form

client/src/pages/forms/state.rs

@@ -1,6 +1,10 @@
 // src/pages/forms/state.rs
 
 use canvas::{DataProvider, AppMode};
+#[cfg(feature = "validation")]
+use canvas::{CharacterLimits, ValidationConfig, ValidationConfigBuilder};
+#[cfg(feature = "validation")]
+use canvas::validation::limits::CountMode;
 use common::proto::komp_ac::search::search_response::Hit;
 use std::collections::HashMap;
 
@@ -39,6 +43,18 @@ pub struct FormState {
     pub autocomplete_loading: bool,
     pub link_display_map: HashMap<usize, String>,
     pub app_mode: AppMode,
+    // Validation 1 (character limits) per field. None = no validation for that field.
+    // Leave room for future rules (patterns, masks, etc.).
+    pub char_limits: Vec<Option<CharLimitsRule>>,
+}
+
+#[cfg(feature = "validation")]
+#[derive(Debug, Clone)]
+pub struct CharLimitsRule {
+    pub min: Option<usize>,
+    pub max: Option<usize>,
+    pub warn_at: Option<usize>,
+    pub count_mode: CountMode,
 }
 
 impl FormState {
@@ -56,6 +72,7 @@ impl FormState {
         fields: Vec<FieldDefinition>,
     ) -> Self {
         let values = vec![String::new(); fields.len()];
+        let len = values.len();
         FormState {
             id: 0,
             profile_name,
@@ -73,6 +90,7 @@ impl FormState {
             autocomplete_loading: false,
             link_display_map: HashMap::new(),
             app_mode: canvas::AppMode::Edit,
+            char_limits: vec![None; len],
         }
     }
 
@@ -256,6 +274,24 @@ impl FormState {
     pub fn set_current_cursor_pos(&mut self, pos: usize) {
         self.current_cursor_pos = pos;
     }
+
+    #[cfg(feature = "validation")]
+    pub fn set_character_limits_rules(
+        &mut self,
+        rules: Vec<Option<CharLimitsRule>>,
+    ) {
+        if rules.len() == self.fields.len() {
+            self.char_limits = rules;
+        } else {
+            tracing::warn!(
+                "Character limits count {} != field count {} for {}.{}",
+                rules.len(),
+                self.fields.len(),
+                self.profile_name,
+                self.table_name
+            );
+        }
+    }
 }
 
 // Step 2: Implement DataProvider for FormState
@@ -282,4 +318,26 @@ impl DataProvider for FormState {
     fn supports_suggestions(&self, field_index: usize) -> bool {
         self.fields.get(field_index).map(|f| f.is_link).unwrap_or(false)
     }
+
+    // Validation 1: Provide character-limit-based validation to canvas
+    // Only compiled when the "validation" feature is enabled on canvas.
+    #[cfg(feature = "validation")]
+    fn validation_config(&self, index: usize) -> Option<ValidationConfig> {
+        let rule = self.char_limits.get(index)?.as_ref()?;
+        let mut limits = match (rule.min, rule.max) {
+            (Some(min), Some(max)) => CharacterLimits::new_range(min, max),
+            (None, Some(max)) => CharacterLimits::new(max),
+            (Some(min), None) => CharacterLimits::new_range(min, usize::MAX),
+            (None, None) => CharacterLimits::new(usize::MAX),
+        };
+        limits = limits.with_count_mode(rule.count_mode);
+        if let Some(warn) = rule.warn_at {
+            limits = limits.with_warning_threshold(warn);
+        }
+        Some(
+            ValidationConfigBuilder::new()
+                .with_character_limits(limits)
+                .build(),
+        )
+    }
 }