ferro_json_ui/

resolve.rs

//! Resolvers for JSON-UI component trees.
//!
//! Walks a `JsonUiView`'s component tree and resolves action handler
//! references to URLs and validation errors to form field error messages.
//! Both resolvers keep ferro-json-ui decoupled from the framework.

use std::collections::HashMap;

use crate::action::Action;
use crate::component::{Component, ComponentNode};
use crate::view::JsonUiView;

/// Resolve a single action using the callback.
fn resolve_action(action: &mut Action, resolver: &impl Fn(&str) -> Option<String>) {
    if action.url.is_none() {
        // Literal paths (starting with "/") are passed through as-is so
        // callers can use Action::get("/dashboard/...") without registering
        // a named route.
        if action.handler.starts_with('/') {
            action.url = Some(action.handler.clone());
            return;
        }
        if let Some(url) = resolver(&action.handler) {
            action.url = Some(url);
        }
    }
}

/// Recursively resolve all actions within a component node.
fn resolve_component_node(node: &mut ComponentNode, resolver: &impl Fn(&str) -> Option<String>) {
    // Resolve the node-level action (any component can have one).
    if let Some(ref mut action) = node.action {
        resolve_action(action, resolver);
    }

    // Recurse into component-specific children.
    match &mut node.component {
        Component::Card(props) => {
            for child in &mut props.children {
                resolve_component_node(child, resolver);
            }
            for child in &mut props.footer {
                resolve_component_node(child, resolver);
            }
        }
        Component::Form(props) => {
            resolve_action(&mut props.action, resolver);
            for field in &mut props.fields {
                resolve_component_node(field, resolver);
            }
        }
        Component::DetailForm(props) => {
            resolve_action(&mut props.action, resolver);
            for field in &mut props.fields {
                resolve_component_node(&mut field.input, resolver);
            }
        }
        Component::Modal(props) => {
            for child in &mut props.children {
                resolve_component_node(child, resolver);
            }
            for child in &mut props.footer {
                resolve_component_node(child, resolver);
            }
        }
        Component::Tabs(props) => {
            for tab in &mut props.tabs {
                for child in &mut tab.children {
                    resolve_component_node(child, resolver);
                }
            }
        }
        Component::Table(props) => {
            if let Some(ref mut row_actions) = props.row_actions {
                for action in row_actions {
                    resolve_action(action, resolver);
                }
            }
        }
        Component::Grid(props) => {
            for child in &mut props.children {
                resolve_component_node(child, resolver);
            }
        }
        Component::Collapsible(props) => {
            for child in &mut props.children {
                resolve_component_node(child, resolver);
            }
        }
        Component::FormSection(props) => {
            for child in &mut props.children {
                resolve_component_node(child, resolver);
            }
        }
        Component::PageHeader(props) => {
            for child in &mut props.actions {
                resolve_component_node(child, resolver);
            }
        }
        Component::ButtonGroup(props) => {
            for child in &mut props.buttons {
                resolve_component_node(child, resolver);
            }
        }
        Component::DropdownMenu(props) => {
            for item in &mut props.items {
                resolve_action(&mut item.action, resolver);
            }
        }
        Component::KanbanBoard(props) => {
            for col in &mut props.columns {
                for child in &mut col.children {
                    resolve_component_node(child, resolver);
                }
            }
        }
        Component::EmptyState(props) => {
            if let Some(ref mut action) = props.action {
                resolve_action(action, resolver);
            }
        }
        Component::Switch(props) => {
            if let Some(ref mut action) = props.action {
                resolve_action(action, resolver);
            }
        }
        Component::DataTable(props) => {
            if let Some(ref mut actions) = props.row_actions {
                for item in actions {
                    resolve_action(&mut item.action, resolver);
                }
            }
        }
        // Leaf components with no children or actions to resolve.
        Component::Button(_)
        | Component::Input(_)
        | Component::Select(_)
        | Component::Alert(_)
        | Component::Badge(_)
        | Component::Text(_)
        | Component::Checkbox(_)
        | Component::Separator(_)
        | Component::DescriptionList(_)
        | Component::Breadcrumb(_)
        | Component::Pagination(_)
        | Component::Progress(_)
        | Component::Avatar(_)
        | Component::Skeleton(_)
        | Component::StatCard(_)
        | Component::Checklist(_)
        | Component::Toast(_)
        | Component::NotificationDropdown(_)
        | Component::Sidebar(_)
        | Component::Header(_)
        | Component::CalendarCell(_)
        | Component::ActionCard(_)
        | Component::ProductTile(_)
        | Component::Image(_)
        | Component::KeyValueEditor(_)
        | Component::RichTextEditor(_)
        | Component::Plugin(_) => {}
    }
}

/// Walk the entire component tree and resolve all action handler names to URLs.
///
/// The resolver callback maps a handler name (e.g. `"users.store"`) to an
/// optional URL (e.g. `Some("/users")`). Actions whose handler cannot be
/// resolved are left with `url: None`.
pub fn resolve_actions(view: &mut JsonUiView, resolver: impl Fn(&str) -> Option<String>) {
    for node in &mut view.components {
        resolve_component_node(node, &resolver);
    }
}

/// Walk the entire component tree and resolve all actions, returning an error
/// for any handler that cannot be resolved.
///
/// Returns `Ok(())` if all handlers resolve successfully, or `Err(Vec<String>)`
/// containing the names of all unresolvable handlers.
pub fn resolve_actions_strict(
    view: &mut JsonUiView,
    resolver: impl Fn(&str) -> Option<String>,
) -> Result<(), Vec<String>> {
    let mut unresolved: Vec<String> = Vec::new();

    let collecting_resolver = |handler: &str| -> Option<String> { resolver(handler) };

    // First resolve everything.
    resolve_actions(view, collecting_resolver);

    // Then collect unresolved handlers by walking the tree again.
    for node in &view.components {
        collect_unresolved_node(node, &mut unresolved);
    }

    if unresolved.is_empty() {
        Ok(())
    } else {
        Err(unresolved)
    }
}

/// Collect handler names from actions that have no resolved URL.
fn collect_unresolved_action(action: &Action, unresolved: &mut Vec<String>) {
    if action.url.is_none() {
        unresolved.push(action.handler.clone());
    }
}

/// Recursively collect unresolved actions from a component node.
fn collect_unresolved_node(node: &ComponentNode, unresolved: &mut Vec<String>) {
    if let Some(ref action) = node.action {
        collect_unresolved_action(action, unresolved);
    }

    match &node.component {
        Component::Card(props) => {
            for child in &props.children {
                collect_unresolved_node(child, unresolved);
            }
            for child in &props.footer {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::Form(props) => {
            collect_unresolved_action(&props.action, unresolved);
            for field in &props.fields {
                collect_unresolved_node(field, unresolved);
            }
        }
        Component::DetailForm(props) => {
            collect_unresolved_action(&props.action, unresolved);
            for field in &props.fields {
                collect_unresolved_node(&field.input, unresolved);
            }
        }
        Component::Modal(props) => {
            for child in &props.children {
                collect_unresolved_node(child, unresolved);
            }
            for child in &props.footer {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::Tabs(props) => {
            for tab in &props.tabs {
                for child in &tab.children {
                    collect_unresolved_node(child, unresolved);
                }
            }
        }
        Component::Table(props) => {
            if let Some(ref row_actions) = props.row_actions {
                for action in row_actions {
                    collect_unresolved_action(action, unresolved);
                }
            }
        }
        Component::Grid(props) => {
            for child in &props.children {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::Collapsible(props) => {
            for child in &props.children {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::FormSection(props) => {
            for child in &props.children {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::PageHeader(props) => {
            for child in &props.actions {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::ButtonGroup(props) => {
            for child in &props.buttons {
                collect_unresolved_node(child, unresolved);
            }
        }
        Component::DropdownMenu(props) => {
            for item in &props.items {
                collect_unresolved_action(&item.action, unresolved);
            }
        }
        Component::KanbanBoard(props) => {
            for col in &props.columns {
                for child in &col.children {
                    collect_unresolved_node(child, unresolved);
                }
            }
        }
        Component::EmptyState(props) => {
            if let Some(ref action) = props.action {
                collect_unresolved_action(action, unresolved);
            }
        }
        Component::Switch(props) => {
            if let Some(ref action) = props.action {
                collect_unresolved_action(action, unresolved);
            }
        }
        Component::DataTable(props) => {
            if let Some(ref actions) = props.row_actions {
                for item in actions {
                    collect_unresolved_action(&item.action, unresolved);
                }
            }
        }
        Component::Button(_)
        | Component::Input(_)
        | Component::Select(_)
        | Component::Alert(_)
        | Component::Badge(_)
        | Component::Text(_)
        | Component::Checkbox(_)
        | Component::Separator(_)
        | Component::DescriptionList(_)
        | Component::Breadcrumb(_)
        | Component::Pagination(_)
        | Component::Progress(_)
        | Component::Avatar(_)
        | Component::Skeleton(_)
        | Component::StatCard(_)
        | Component::Checklist(_)
        | Component::Toast(_)
        | Component::NotificationDropdown(_)
        | Component::Sidebar(_)
        | Component::Header(_)
        | Component::CalendarCell(_)
        | Component::ActionCard(_)
        | Component::ProductTile(_)
        | Component::Image(_)
        | Component::KeyValueEditor(_)
        | Component::RichTextEditor(_)
        | Component::Plugin(_) => {}
    }
}

// ---------------------------------------------------------------------------
// Validation error resolution
// ---------------------------------------------------------------------------

/// Walk the component tree and set the first validation error message on each
/// matching form field component (Input, Select, Checkbox, Switch).
///
/// Only fields whose `error` is currently `None` are updated; explicit errors
/// set by the caller take priority.
pub fn resolve_errors(view: &mut JsonUiView, errors: &HashMap<String, Vec<String>>) {
    for node in &mut view.components {
        resolve_errors_node(node, errors, false);
    }
}

/// Walk the component tree and set all validation error messages (joined with
/// `". "`) on each matching form field component.
///
/// Same precedence rule: existing errors are not overwritten.
pub fn resolve_errors_all(view: &mut JsonUiView, errors: &HashMap<String, Vec<String>>) {
    for node in &mut view.components {
        resolve_errors_node(node, errors, true);
    }
}

/// Set the error string on a form field if the errors map contains its field name.
fn set_field_error(
    error_slot: &mut Option<String>,
    field: &str,
    errors: &HashMap<String, Vec<String>>,
    all: bool,
) {
    if error_slot.is_some() {
        return; // explicit error takes priority
    }
    if let Some(messages) = errors.get(field) {
        if !messages.is_empty() {
            if all {
                *error_slot = Some(messages.join(". "));
            } else {
                *error_slot = Some(messages[0].clone());
            }
        }
    }
}

/// Recursively resolve validation errors within a component node.
fn resolve_errors_node(node: &mut ComponentNode, errors: &HashMap<String, Vec<String>>, all: bool) {
    match &mut node.component {
        Component::Input(props) => {
            set_field_error(&mut props.error, &props.field, errors, all);
        }
        Component::Select(props) => {
            set_field_error(&mut props.error, &props.field, errors, all);
        }
        Component::Checkbox(props) => {
            set_field_error(&mut props.error, &props.field, errors, all);
        }
        Component::Switch(props) => {
            set_field_error(&mut props.error, &props.field, errors, all);
        }
        Component::Card(props) => {
            for child in &mut props.children {
                resolve_errors_node(child, errors, all);
            }
            for child in &mut props.footer {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::Form(props) => {
            for field in &mut props.fields {
                resolve_errors_node(field, errors, all);
            }
        }
        Component::DetailForm(props) => {
            for field in &mut props.fields {
                resolve_errors_node(&mut field.input, errors, all);
            }
        }
        Component::Modal(props) => {
            for child in &mut props.children {
                resolve_errors_node(child, errors, all);
            }
            for child in &mut props.footer {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::Tabs(props) => {
            for tab in &mut props.tabs {
                for child in &mut tab.children {
                    resolve_errors_node(child, errors, all);
                }
            }
        }
        Component::Grid(props) => {
            for child in &mut props.children {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::Collapsible(props) => {
            for child in &mut props.children {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::FormSection(props) => {
            for child in &mut props.children {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::PageHeader(props) => {
            for child in &mut props.actions {
                resolve_errors_node(child, errors, all);
            }
        }
        Component::ButtonGroup(props) => {
            for child in &mut props.buttons {
                resolve_errors_node(child, errors, all);
            }
        }
        // Leaf components with no form field semantics.
        Component::Table(_)
        | Component::Button(_)
        | Component::Alert(_)
        | Component::Badge(_)
        | Component::Text(_)
        | Component::Separator(_)
        | Component::DescriptionList(_)
        | Component::Breadcrumb(_)
        | Component::Pagination(_)
        | Component::Progress(_)
        | Component::Avatar(_)
        | Component::Skeleton(_)
        | Component::StatCard(_)
        | Component::Checklist(_)
        | Component::Toast(_)
        | Component::NotificationDropdown(_)
        | Component::Sidebar(_)
        | Component::Header(_)
        | Component::EmptyState(_)
        | Component::DropdownMenu(_)
        | Component::KanbanBoard(_)
        | Component::CalendarCell(_)
        | Component::ActionCard(_)
        | Component::ProductTile(_)
        | Component::DataTable(_)
        | Component::Image(_)
        | Component::Plugin(_) => {}
        Component::KeyValueEditor(props) => {
            set_field_error(&mut props.error, &props.field, errors, all);
        }
        Component::RichTextEditor(props) => {
            set_field_error(&mut props.error, &props.name, errors, all);
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::action::HttpMethod;
    use crate::component::*;

    /// Helper to build a simple action.
    fn make_action(handler: &str) -> Action {
        Action {
            handler: handler.to_string(),
            url: None,
            method: HttpMethod::Post,
            confirm: None,
            on_success: None,
            on_error: None,
            target: None,
        }
    }

    /// Helper resolver that maps known handlers to URLs.
    fn test_resolver(handler: &str) -> Option<String> {
        match handler {
            "users.store" => Some("/users".to_string()),
            "users.show" => Some("/users/{id}".to_string()),
            "users.destroy" => Some("/users/{id}".to_string()),
            "users.create" => Some("/users/create".to_string()),
            "posts.index" => Some("/posts".to_string()),
            _ => None,
        }
    }

    #[test]
    fn resolve_button_with_action() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "btn".to_string(),
            component: Component::Button(ButtonProps {
                label: "Create".to_string(),
                variant: ButtonVariant::Default,
                size: Size::Default,
                disabled: None,
                icon: None,
                icon_position: None,
                button_type: None,
            }),
            action: Some(make_action("users.store")),
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        assert_eq!(
            view.components[0].action.as_ref().unwrap().url,
            Some("/users".to_string())
        );
    }

    #[test]
    fn resolve_nested_card_children() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "card".to_string(),
            component: Component::Card(CardProps {
                title: "Users".to_string(),
                description: None,
                max_width: None,
                children: vec![ComponentNode {
                    key: "btn".to_string(),
                    component: Component::Button(ButtonProps {
                        label: "Create".to_string(),
                        variant: ButtonVariant::Default,
                        size: Size::Default,
                        disabled: None,
                        icon: None,
                        icon_position: None,
                        button_type: None,
                    }),
                    action: Some(make_action("users.create")),
                    visibility: None,
                }],
                footer: vec![ComponentNode {
                    key: "footer-btn".to_string(),
                    component: Component::Button(ButtonProps {
                        label: "Save".to_string(),
                        variant: ButtonVariant::Default,
                        size: Size::Default,
                        disabled: None,
                        icon: None,
                        icon_position: None,
                        button_type: None,
                    }),
                    action: Some(make_action("users.store")),
                    visibility: None,
                }],
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::Card(props) => {
                assert_eq!(
                    props.children[0].action.as_ref().unwrap().url,
                    Some("/users/create".to_string())
                );
                assert_eq!(
                    props.footer[0].action.as_ref().unwrap().url,
                    Some("/users".to_string())
                );
            }
            _ => panic!("expected Card"),
        }
    }

    #[test]
    fn resolve_form_action() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "form".to_string(),
            component: Component::Form(FormProps {
                action: make_action("users.store"),
                fields: vec![ComponentNode {
                    key: "name".to_string(),
                    component: Component::Input(InputProps {
                        field: "name".to_string(),
                        label: "Name".to_string(),
                        input_type: InputType::Text,
                        placeholder: None,
                        required: None,
                        disabled: None,
                        error: None,
                        description: None,
                        default_value: None,
                        data_path: None,
                        step: None,
                        list: None,
                    }),
                    action: None,
                    visibility: None,
                }],
                method: None,
                guard: None,
                max_width: None,
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::Form(props) => {
                assert_eq!(props.action.url, Some("/users".to_string()));
            }
            _ => panic!("expected Form"),
        }
    }

    #[test]
    fn resolve_table_row_actions() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "table".to_string(),
            component: Component::Table(TableProps {
                columns: vec![Column {
                    key: "name".to_string(),
                    label: "Name".to_string(),
                    format: None,
                }],
                data_path: "/data/users".to_string(),
                row_actions: Some(vec![
                    make_action("users.show"),
                    make_action("users.destroy"),
                ]),
                empty_message: None,
                sortable: None,
                sort_column: None,
                sort_direction: None,
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::Table(props) => {
                let row_actions = props.row_actions.as_ref().unwrap();
                assert_eq!(row_actions[0].url, Some("/users/{id}".to_string()));
                assert_eq!(row_actions[1].url, Some("/users/{id}".to_string()));
            }
            _ => panic!("expected Table"),
        }
    }

    #[test]
    fn resolve_tabs_children() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "tabs".to_string(),
            component: Component::Tabs(TabsProps {
                default_tab: "general".to_string(),
                tabs: vec![
                    Tab {
                        value: "general".to_string(),
                        label: "General".to_string(),
                        children: vec![ComponentNode {
                            key: "btn1".to_string(),
                            component: Component::Button(ButtonProps {
                                label: "Save".to_string(),
                                variant: ButtonVariant::Default,
                                size: Size::Default,
                                disabled: None,
                                icon: None,
                                icon_position: None,
                                button_type: None,
                            }),
                            action: Some(make_action("users.store")),
                            visibility: None,
                        }],
                    },
                    Tab {
                        value: "posts".to_string(),
                        label: "Posts".to_string(),
                        children: vec![ComponentNode {
                            key: "btn2".to_string(),
                            component: Component::Button(ButtonProps {
                                label: "View Posts".to_string(),
                                variant: ButtonVariant::Default,
                                size: Size::Default,
                                disabled: None,
                                icon: None,
                                icon_position: None,
                                button_type: None,
                            }),
                            action: Some(make_action("posts.index")),
                            visibility: None,
                        }],
                    },
                ],
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::Tabs(props) => {
                assert_eq!(
                    props.tabs[0].children[0].action.as_ref().unwrap().url,
                    Some("/users".to_string())
                );
                assert_eq!(
                    props.tabs[1].children[0].action.as_ref().unwrap().url,
                    Some("/posts".to_string())
                );
            }
            _ => panic!("expected Tabs"),
        }
    }

    #[test]
    fn resolve_modal_children_and_footer() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "modal".to_string(),
            component: Component::Modal(ModalProps {
                id: "modal-confirm".to_string(),
                title: "Confirm".to_string(),
                description: None,
                children: vec![ComponentNode {
                    key: "info".to_string(),
                    component: Component::Text(TextProps {
                        content: "Are you sure?".to_string(),
                        element: TextElement::P,
                    }),
                    action: None,
                    visibility: None,
                }],
                footer: vec![ComponentNode {
                    key: "confirm-btn".to_string(),
                    component: Component::Button(ButtonProps {
                        label: "Delete".to_string(),
                        variant: ButtonVariant::Destructive,
                        size: Size::Default,
                        disabled: None,
                        icon: None,
                        icon_position: None,
                        button_type: None,
                    }),
                    action: Some(make_action("users.destroy")),
                    visibility: None,
                }],
                trigger_label: Some("Open".to_string()),
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::Modal(props) => {
                assert_eq!(
                    props.footer[0].action.as_ref().unwrap().url,
                    Some("/users/{id}".to_string())
                );
            }
            _ => panic!("expected Modal"),
        }
    }

    #[test]
    fn unresolvable_handler_leaves_url_none() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "btn".to_string(),
            component: Component::Button(ButtonProps {
                label: "Unknown".to_string(),
                variant: ButtonVariant::Default,
                size: Size::Default,
                disabled: None,
                icon: None,
                icon_position: None,
                button_type: None,
            }),
            action: Some(make_action("nonexistent.handler")),
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        assert_eq!(view.components[0].action.as_ref().unwrap().url, None);
    }

    #[test]
    fn strict_with_missing_handler_returns_error() {
        let mut view = JsonUiView::new()
            .component(ComponentNode {
                key: "btn1".to_string(),
                component: Component::Button(ButtonProps {
                    label: "OK".to_string(),
                    variant: ButtonVariant::Default,
                    size: Size::Default,
                    disabled: None,
                    icon: None,
                    icon_position: None,
                    button_type: None,
                }),
                action: Some(make_action("users.store")),
                visibility: None,
            })
            .component(ComponentNode {
                key: "btn2".to_string(),
                component: Component::Button(ButtonProps {
                    label: "Bad".to_string(),
                    variant: ButtonVariant::Default,
                    size: Size::Default,
                    disabled: None,
                    icon: None,
                    icon_position: None,
                    button_type: None,
                }),
                action: Some(make_action("unknown.handler")),
                visibility: None,
            });

        let result = resolve_actions_strict(&mut view, test_resolver);
        assert!(result.is_err());
        let errors = result.unwrap_err();
        assert_eq!(errors, vec!["unknown.handler"]);

        // The known handler should still be resolved.
        assert_eq!(
            view.components[0].action.as_ref().unwrap().url,
            Some("/users".to_string())
        );
    }

    #[test]
    fn strict_with_all_resolved_returns_ok() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "btn".to_string(),
            component: Component::Button(ButtonProps {
                label: "Create".to_string(),
                variant: ButtonVariant::Default,
                size: Size::Default,
                disabled: None,
                icon: None,
                icon_position: None,
                button_type: None,
            }),
            action: Some(make_action("users.store")),
            visibility: None,
        });

        let result = resolve_actions_strict(&mut view, test_resolver);
        assert!(result.is_ok());
    }

    // -----------------------------------------------------------------------
    // resolve_errors tests
    // -----------------------------------------------------------------------

    fn make_errors(pairs: &[(&str, &[&str])]) -> HashMap<String, Vec<String>> {
        pairs
            .iter()
            .map(|(k, v)| (k.to_string(), v.iter().map(|s| s.to_string()).collect()))
            .collect()
    }

    fn make_input_node(key: &str, field: &str) -> ComponentNode {
        ComponentNode {
            key: key.to_string(),
            component: Component::Input(InputProps {
                field: field.to_string(),
                label: field.to_string(),
                input_type: InputType::Text,
                placeholder: None,
                required: None,
                disabled: None,
                error: None,
                description: None,
                default_value: None,
                data_path: None,
                step: None,
                list: None,
            }),
            action: None,
            visibility: None,
        }
    }

    #[test]
    fn resolve_errors_populates_input_error() {
        let mut view = JsonUiView::new().component(make_input_node("email-input", "email"));
        let errors = make_errors(&[("email", &["Email is required"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Input(props) => {
                assert_eq!(props.error, Some("Email is required".to_string()));
            }
            _ => panic!("expected Input"),
        }
    }

    #[test]
    fn resolve_errors_populates_select_error() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "role-select".to_string(),
            component: Component::Select(SelectProps {
                field: "role".to_string(),
                label: "Role".to_string(),
                options: vec![SelectOption {
                    value: "admin".to_string(),
                    label: "Admin".to_string(),
                }],
                placeholder: None,
                required: None,
                disabled: None,
                error: None,
                description: None,
                default_value: None,
                data_path: None,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[("role", &["Role is required"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Select(props) => {
                assert_eq!(props.error, Some("Role is required".to_string()));
            }
            _ => panic!("expected Select"),
        }
    }

    #[test]
    fn resolve_errors_populates_checkbox_error() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "terms-checkbox".to_string(),
            component: Component::Checkbox(CheckboxProps {
                field: "terms".to_string(),
                value: None,
                label: "Accept Terms".to_string(),
                description: None,
                checked: None,
                data_path: None,
                required: None,
                disabled: None,
                error: None,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[("terms", &["You must accept the terms"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Checkbox(props) => {
                assert_eq!(props.error, Some("You must accept the terms".to_string()));
            }
            _ => panic!("expected Checkbox"),
        }
    }

    #[test]
    fn resolve_errors_populates_switch_error() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "notif-switch".to_string(),
            component: Component::Switch(SwitchProps {
                field: "notifications".to_string(),
                label: "Notifications".to_string(),
                description: None,
                checked: None,
                data_path: None,
                required: None,
                disabled: None,
                error: None,
                action: None,
                compact: false,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[("notifications", &["Must enable notifications"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Switch(props) => {
                assert_eq!(props.error, Some("Must enable notifications".to_string()));
            }
            _ => panic!("expected Switch"),
        }
    }

    #[test]
    fn resolve_errors_does_not_overwrite_existing() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "email-input".to_string(),
            component: Component::Input(InputProps {
                field: "email".to_string(),
                label: "Email".to_string(),
                input_type: InputType::Email,
                placeholder: None,
                required: None,
                disabled: None,
                error: Some("Custom error".to_string()),
                description: None,
                default_value: None,
                data_path: None,
                step: None,
                list: None,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[("email", &["Validation error"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Input(props) => {
                assert_eq!(props.error, Some("Custom error".to_string()));
            }
            _ => panic!("expected Input"),
        }
    }

    #[test]
    fn resolve_errors_nested_in_form() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "form".to_string(),
            component: Component::Form(FormProps {
                action: make_action("users.store"),
                fields: vec![
                    make_input_node("name-input", "name"),
                    make_input_node("email-input", "email"),
                ],
                method: None,
                guard: None,
                max_width: None,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[
            ("name", &["Name is required"]),
            ("email", &["Email is invalid"]),
        ]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Form(props) => {
                match &props.fields[0].component {
                    Component::Input(p) => {
                        assert_eq!(p.error, Some("Name is required".to_string()));
                    }
                    _ => panic!("expected Input"),
                }
                match &props.fields[1].component {
                    Component::Input(p) => {
                        assert_eq!(p.error, Some("Email is invalid".to_string()));
                    }
                    _ => panic!("expected Input"),
                }
            }
            _ => panic!("expected Form"),
        }
    }

    #[test]
    fn resolve_errors_nested_in_card() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "card".to_string(),
            component: Component::Card(CardProps {
                title: "User".to_string(),
                description: None,
                children: vec![make_input_node("name-input", "name")],
                footer: vec![],
                max_width: None,
            }),
            action: None,
            visibility: None,
        });
        let errors = make_errors(&[("name", &["Name is required"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Card(props) => match &props.children[0].component {
                Component::Input(p) => {
                    assert_eq!(p.error, Some("Name is required".to_string()));
                }
                _ => panic!("expected Input"),
            },
            _ => panic!("expected Card"),
        }
    }

    #[test]
    fn resolve_errors_no_matching_field() {
        let mut view = JsonUiView::new().component(make_input_node("email-input", "email"));
        let errors = make_errors(&[("unknown_field", &["Some error"])]);
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Input(props) => {
                assert_eq!(props.error, None);
            }
            _ => panic!("expected Input"),
        }
    }

    #[test]
    fn resolve_errors_all_concatenates_messages() {
        let mut view = JsonUiView::new().component(make_input_node("email-input", "email"));
        let errors = make_errors(&[("email", &["Too short", "Invalid format", "Already taken"])]);
        resolve_errors_all(&mut view, &errors);

        match &view.components[0].component {
            Component::Input(props) => {
                assert_eq!(
                    props.error,
                    Some("Too short. Invalid format. Already taken".to_string())
                );
            }
            _ => panic!("expected Input"),
        }
    }

    #[test]
    fn resolve_errors_empty_errors_map() {
        let mut view = JsonUiView::new().component(make_input_node("email-input", "email"));
        let errors: HashMap<String, Vec<String>> = HashMap::new();
        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::Input(props) => {
                assert_eq!(props.error, None);
            }
            _ => panic!("expected Input"),
        }
    }

    // ── DetailForm resolver tests (Phase 147, Wave 0 RED) ─────────────────

    #[test]
    fn resolve_detail_form_action() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "df".to_string(),
            component: Component::DetailForm(DetailFormProps {
                mode: EditMode::Edit,
                action: make_action("users.update"),
                fields: vec![],
                edit_url: "/users/1?mode=edit".to_string(),
                cancel_url: "/users/1".to_string(),
                edit_label: None,
                save_label: None,
                cancel_label: None,
                method: None,
            }),
            action: None,
            visibility: None,
        });

        // Resolver knows "users.update" → "/users/1" (add arm if missing in test_resolver).
        resolve_actions(&mut view, |h: &str| match h {
            "users.update" => Some("/users/1".to_string()),
            _ => test_resolver(h),
        });

        match &view.components[0].component {
            Component::DetailForm(props) => {
                assert_eq!(
                    props.action.url.as_deref(),
                    Some("/users/1"),
                    "resolver must populate DetailForm action.url from handler"
                );
            }
            _ => panic!("expected Component::DetailForm"),
        }
    }

    #[test]
    fn resolve_does_not_touch_edit_or_cancel_url() {
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "df".to_string(),
            component: Component::DetailForm(DetailFormProps {
                mode: EditMode::View,
                action: make_action("users.update"),
                fields: vec![],
                edit_url: "RAW_EDIT".to_string(),
                cancel_url: "RAW_CANCEL".to_string(),
                edit_label: None,
                save_label: None,
                cancel_label: None,
                method: None,
            }),
            action: None,
            visibility: None,
        });

        resolve_actions(&mut view, test_resolver);

        match &view.components[0].component {
            Component::DetailForm(props) => {
                assert_eq!(
                    props.edit_url, "RAW_EDIT",
                    "edit_url must not be resolved (D-16)"
                );
                assert_eq!(
                    props.cancel_url, "RAW_CANCEL",
                    "cancel_url must not be resolved (D-16)"
                );
            }
            _ => panic!("expected Component::DetailForm"),
        }
    }

    #[test]
    fn resolve_errors_propagates_into_detail_form_fields() {
        // DetailField.input holds an Input; validation error against field name "name"
        // should attach to the nested InputProps.error after resolve_errors runs.
        let mut view = JsonUiView::new().component(ComponentNode {
            key: "df".to_string(),
            component: Component::DetailForm(DetailFormProps {
                mode: EditMode::Edit,
                action: make_action("users.update"),
                fields: vec![DetailField {
                    label: "Name".to_string(),
                    value: "Ada".to_string(),
                    input: ComponentNode::input(
                        "name",
                        InputProps {
                            field: "name".to_string(),
                            label: "".to_string(),
                            input_type: InputType::Text,
                            placeholder: None,
                            required: None,
                            disabled: None,
                            error: None,
                            description: None,
                            default_value: None,
                            data_path: None,
                            step: None,
                            list: None,
                        },
                    ),
                }],
                edit_url: "/users/1?mode=edit".to_string(),
                cancel_url: "/users/1".to_string(),
                edit_label: None,
                save_label: None,
                cancel_label: None,
                method: None,
            }),
            action: None,
            visibility: None,
        });

        let mut errors = HashMap::new();
        errors.insert("name".to_string(), vec!["required".to_string()]);

        resolve_errors(&mut view, &errors);

        match &view.components[0].component {
            Component::DetailForm(props) => match &props.fields[0].input.component {
                Component::Input(ip) => assert_eq!(
                    ip.error.as_deref(),
                    Some("required"),
                    "validation error must propagate into nested Input inside DetailForm"
                ),
                other => panic!("expected Input inside DetailField, got {other:?}"),
            },
            _ => panic!("expected Component::DetailForm"),
        }
    }
}