refactor(controllers): Unify event flow for controllers (#41)

Cargo.toml

@@ -2,7 +2,7 @@
 
 resolver = "2"
 
-members = ["./app", "./app/api_proc_macro"]
+members = ["./app", "./app/input_mapping/*"]
 
 [workspace.package]
 version = "0.1.0"
@@ -11,6 +11,8 @@ authors = ["mertwole"]
 
 [workspace.dependencies]
 api-proc-macro = { path = "./app/api_proc_macro" }
+input-mapping-derive = { path = "./app/input_mapping/derive" }
+input-mapping-common = { path = "./app/input_mapping/common" }
 
 binance_spot_connector_rust = "1.1.0"
 bs58 = "0.5.1"

app/Cargo.toml

@@ -6,6 +6,8 @@ authors.workspace = true
 
 [dependencies]
 api-proc-macro.workspace = true
+input-mapping-derive.workspace = true
+input-mapping-common.workspace = true
 
 binance_spot_connector_rust.workspace = true
 bs58.workspace = true

app/input_mapping/common/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "input-mapping-common"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+
+[dependencies]
+ratatui.workspace = true

app/input_mapping/common/src/lib.rs

@@ -0,0 +1,41 @@
+use ratatui::crossterm::event::{Event, KeyCode};
+
+pub trait InputMappingT: Sized {
+    fn get_mapping() -> InputMapping;
+
+    fn map_event(event: Event) -> Option<Self>;
+}
+
+#[derive(Debug)]
+pub struct InputMapping {
+    pub mapping: Vec<MappingEntry>,
+}
+
+impl InputMapping {
+    pub fn merge(mut self, mut other: InputMapping) -> Self {
+        self.mapping.append(&mut other.mapping);
+        self
+    }
+}
+
+#[derive(Debug)]
+pub struct MappingEntry {
+    pub key: KeyCode,
+    pub description: String,
+}
+
+pub trait KeyCodeConversions {
+    fn convert(self) -> KeyCode;
+}
+
+impl KeyCodeConversions for char {
+    fn convert(self) -> KeyCode {
+        KeyCode::Char(self)
+    }
+}
+
+impl KeyCodeConversions for KeyCode {
+    fn convert(self) -> KeyCode {
+        self
+    }
+}

app/input_mapping/derive/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "input-mapping-derive"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+
+[lib]
+proc-macro = true
+
+[dependencies]
+input-mapping-common.workspace = true
+
+itertools.workspace = true
+proc-macro2.workspace = true
+quote.workspace = true
+syn.workspace = true

app/input_mapping/derive/src/lib.rs

@@ -0,0 +1,183 @@
+use proc_macro2::{Literal, TokenStream};
+use quote::ToTokens;
+use syn::{parse_macro_input, Expr, Fields, ItemEnum, Lit, Meta, MetaNameValue, Variant};
+
+#[macro_use]
+extern crate quote;
+extern crate proc_macro;
+extern crate syn;
+
+#[proc_macro_derive(InputMapping, attributes(key, description))]
+pub fn derive_mapping(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    let item_enum = parse_macro_input!(input as ItemEnum);
+    let trait_impl = generate_trait_impl(item_enum);
+
+    proc_macro::TokenStream::from(trait_impl)
+}
+
+// TODO: Add check that mappings don't overlap.
+fn generate_trait_impl(item_enum: ItemEnum) -> TokenStream {
+    let (unit, to_be_flattened): (Vec<_>, Vec<_>) = item_enum
+        .variants
+        .into_iter()
+        .partition(|variant| matches!(variant.fields, Fields::Unit));
+
+    let mapping_entries = unit.into_iter().map(generate_mapping_entry);
+
+    let mapping_constructors = mapping_entries.clone().map(|entry| {
+        let key = entry.key;
+        let description = entry.description;
+
+        quote! {
+            ::input_mapping_common::MappingEntry {
+                key: #key.convert(),
+                description: (#description).to_string(),
+            }
+        }
+    });
+
+    let mapping_matchers = mapping_entries.map(|entry| {
+        let key = entry.key;
+        let event = entry.event;
+
+        quote! {
+            ::ratatui::crossterm::event::Event::Key(::ratatui::crossterm::event::KeyEvent {
+                kind: ::ratatui::crossterm::event::KeyEventKind::Press,
+                code,
+                ..
+            }) if code == #key.convert() => ::std::option::Option::Some(Self:: #event)
+        }
+    });
+
+    let get_mapping_flattening = to_be_flattened.iter().map(|variant| {
+        let field_ty = match &variant.fields {
+            Fields::Unnamed(fields) => {
+                let fields = &fields.unnamed;
+                if fields.len() != 1 {
+                    panic!("Multiple unnamed fields are not supported");
+                }
+                &fields.first().expect("fields.len() checked to be = 1").ty
+            }
+            Fields::Unit => panic!("Unit fields have been filtered above"),
+            Fields::Named(_) => panic!("Named variant fields are not supported"),
+        };
+
+        quote! {
+            .merge(#field_ty ::get_mapping())
+        }
+    });
+
+    let map_event_flattening = to_be_flattened.iter().map(|variant| {
+        let field_ty = match &variant.fields {
+            Fields::Unnamed(fields) => {
+                let fields = &fields.unnamed;
+                if fields.len() != 1 {
+                    panic!("Multiple unnamed fields are not supported");
+                }
+                &fields.first().expect("fields.len() checked to be = 1").ty
+            }
+            Fields::Unit => panic!("Unit fields have been filtered above"),
+            Fields::Named(_) => panic!("Named variant fields are not supported"),
+        };
+
+        let ident = &variant.ident;
+
+        quote! {
+            .or_else(|| {
+                #field_ty ::map_event(event).map(Self:: #ident)
+            })
+        }
+    });
+
+    let ident = item_enum.ident;
+
+    quote! {
+        impl ::input_mapping_common::InputMappingT for #ident {
+            fn get_mapping() -> ::input_mapping_common::InputMapping {
+                use ::input_mapping_common::KeyCodeConversions;
+
+                ::input_mapping_common::InputMapping {
+                    mapping: vec![
+                        #(#mapping_constructors,)*
+                    ]
+                }
+
+                #(#get_mapping_flattening)*
+            }
+
+            fn map_event(event: ::ratatui::crossterm::event::Event) -> ::std::option::Option<Self> {
+                use ::input_mapping_common::KeyCodeConversions;
+
+                match event {
+                    #(#mapping_matchers,)*
+                    _ => None,
+                }
+
+                #(#map_event_flattening)*
+            }
+        }
+    }
+}
+
+struct MappingEntry {
+    key: TokenStream,
+    description: TokenStream,
+    event: TokenStream,
+}
+
+fn generate_mapping_entry(variant: Variant) -> MappingEntry {
+    let mut key: Option<TokenStream> = None;
+    let mut description: Option<TokenStream> = None;
+
+    for attr in &variant.attrs {
+        match &attr.meta {
+            Meta::NameValue(MetaNameValue { path, value, .. }) => {
+                if path.is_ident("key") {
+                    if key.is_some() {
+                        panic!("Duplicate definition for attribute: key");
+                    }
+
+                    key = Some(match value {
+                        Expr::Lit(lit) => match &lit.lit {
+                            Lit::Str(str) => str.value().parse().expect("Invalid expression"),
+                            Lit::Char(char) => char.to_token_stream(),
+                            _ => {
+                                unimplemented!("Values other than string or char are not supported")
+                            }
+                        },
+                        _ => unimplemented!(),
+                    });
+
+                    //key = Some(value.into_token_stream());
+                } else if path.is_ident("description") {
+                    if description.is_some() {
+                        panic!("Duplicate definition for attribute: description");
+                    }
+
+                    description = Some(value.into_token_stream());
+                }
+            }
+            _ => continue,
+        }
+    }
+
+    let key = key.unwrap_or_else(|| {
+        let key = variant
+            .ident
+            .to_string()
+            .chars()
+            .next()
+            .expect("Non-empty identifier expected")
+            .to_ascii_lowercase();
+
+        Literal::character(key).into_token_stream()
+    });
+
+    let description = description.unwrap_or_else(|| Literal::string("").into_token_stream());
+
+    MappingEntry {
+        key,
+        description,
+        event: variant.ident.to_token_stream(),
+    }
+}

app/input_mapping/tests/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "input-mapping-tests"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+
+[dependencies]
+input-mapping-derive.workspace = true
+input-mapping-common.workspace = true
+
+ratatui.workspace = true

app/input_mapping/tests/src/lib.rs

@@ -0,0 +1,50 @@
+#![cfg(test)]
+
+use std::collections::HashMap;
+
+use input_mapping_common::InputMappingT;
+use input_mapping_derive::InputMapping;
+use ratatui::crossterm::event::KeyCode;
+
+#[derive(InputMapping)]
+enum TestEnum {
+    #[key = 'a']
+    One,
+
+    #[description = "test"]
+    Two,
+
+    #[allow(dead_code)]
+    Nested(Nested),
+}
+
+#[derive(InputMapping)]
+enum Nested {
+    #[description = "four_test"]
+    Four,
+
+    #[key = "KeyCode::Up"]
+    #[description = "up"]
+    Five,
+
+    Six,
+}
+
+#[test]
+fn test_input_mapping_generated_as_expected() {
+    let mapping = TestEnum::get_mapping();
+    let mapping: HashMap<_, _> = mapping
+        .mapping
+        .into_iter()
+        .map(|map| (map.key, map.description))
+        .collect();
+
+    assert_eq!(mapping.len(), 5);
+    assert_eq!(
+        mapping.get(&KeyCode::Char('f')),
+        Some(&"four_test".to_string())
+    );
+    assert_eq!(mapping.get(&KeyCode::Char('t')), Some(&"test".to_string()));
+    assert_eq!(mapping.get(&KeyCode::Char('s')), Some(&"".to_string()));
+    assert_eq!(mapping.get(&KeyCode::Up), Some(&"up".to_string()));
+}