feat: begin implementation of value display

src/common/schema_node.rs

@@ -0,0 +1,97 @@
+use std::collections::HashMap;
+use serde::{Deserialize, Serialize};
+
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub enum SchemaType {
+    String,
+    Number,
+    List,
+    Map
+}
+
+/// # Schema Node
+///
+/// This is used to create a schema that is used in the [`ValueDisplay`] component. It stores all
+/// required information for the display, specifically where to find the data and how to display it.
+/// It covers all `ValueType` variants, however for data storage and DX it uses a `SchemaType`
+/// instead.
+///
+/// Some examples are as follows, using the fluent builder notation:
+///  - Displaying a single `ValueType::String` from the data map at the key `example_one`:
+///     ```
+///     SchemaNode::new(SchemaType::String).header("The example string")
+///     ```
+///  - Displaying a `ValueType::List` which contains only `ValueType::String` entries:
+///     ```
+///     SchemaNode::new(SchemaType::List)
+///         .header("The example list")
+///         .item_template(SchemaNode::new(SchemaType::String).header(""))
+///     ```
+///  - Displaying a `ValueType::Map` which contains a name and age:
+///     ```
+///     SchemaType::new(SchemaType::Map)
+///         .header("The example map")
+///         .child("first_name", SchemaNode::new(SchemaType::String).header("First Name:"))
+///         .child("age", SchemaNode::new(SchemaType::Number).header("Age:"))
+///     ```
+///  - Put it all together: a `ValueType::List` which contains `ValueType::Map` entries, each of
+///    which also contains the name and age from the previous example:
+///     ```
+///     SchemaNode::new(SchemaType::List)
+///         .header("The example map list")
+///         .item_template(
+///             SchemaNode::new(SchemaType::Map)
+///                 .header("The example map from earlier")
+///                 .child("first_name", SchemaNode::new(SchemaType::String).header("First Name:"))
+///                 .child("age", SchemaNode::new(SchemaType::Number).header("Age:"))
+///         )
+///     ```
+///
+/// This schema allows for definitive typing and styling for every level of the data display.
+///
+/// ## Important Notes
+///
+/// This schema does not currently support display of a single nested member, like a single map
+/// within a list. This means that you will have to display any listed or mapped information as a
+/// list. Consider this when designing the data.
+#[derive(Deserialize, Serialize, Debug, Clone)]
+pub struct SchemaNode {
+    /// The datatype of the data found using the `data_member` key.
+    pub data_type: SchemaType,
+    /// The header of this display.
+    pub header: String,
+    /// When used with a SchemaType::List, this determines the datatype and children for every entry
+    /// in the list. Some examples include a list of maps, where we use the `item_template` to define
+    /// the SchemaType::Map, and all its children. This is then mapped across all entries in the list,
+    /// where any entries that do not match the template are skipped.
+    pub item_template: Option<Box<SchemaNode>>,
+    /// When used with a SchemaType::Map, this determines what children from the map are displayed
+    /// and how. It is ignored with all other SchemaType variants.
+    pub children: HashMap<String, SchemaNode>,
+}
+
+impl SchemaNode {
+    pub fn new(data_type: SchemaType) -> Self {
+        SchemaNode {
+            data_type,
+            header: "".to_string(),
+            item_template: None,
+            children: HashMap::new(),
+        }
+    }
+
+    pub fn header(mut self, header: impl Into<String>) -> Self {
+        self.header = header.into();
+        self
+    }
+
+    pub fn child(mut self, data_member: impl Into<String>, node: SchemaNode) -> Self {
+        self.children.insert(data_member.into(), node);
+        self
+    }
+
+    pub fn item_template(mut self, node: SchemaNode) -> Self {
+        self.item_template = Some(Box::new(node));
+        self
+    }
+}