1 files changed, 163 insertions, 0 deletions
diff --git a/mingling_macros/src/dispatcher.rs b/mingling_macros/src/dispatcher.rs
new file mode 100644
index 0000000..6223a81
--- /dev/null
+++ b/mingling_macros/src/dispatcher.rs
@@ -0,0 +1,163 @@
+//! Dispatcher Chain and Dispatcher Render Macros
+//!
+//! This module provides macros for creating dispatcher chain and dispatcher render structs
+//! with automatic implementations of the `Dispatcher` trait.
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::parse::{Parse, ParseStream};
+use syn::{Ident, Result as SynResult, Token};
+
+enum DispatcherChainInput {
+    Explicit {
+        group_name: Ident,
+        command_name: syn::LitStr,
+        command_struct: Ident,
+        pack: Ident,
+    },
+    Default {
+        command_name: syn::LitStr,
+        command_struct: Ident,
+        pack: Ident,
+    },
+}
+
+impl Parse for DispatcherChainInput {
+    fn parse(input: ParseStream) -> SynResult<Self> {
+        let lookahead = input.lookahead1();
+
+        if lookahead.peek(Ident) && input.peek2(Token![,]) && input.peek3(syn::LitStr) {
+            let group_name = input.parse()?;
+            input.parse::<Token![,]>()?;
+            let command_name = input.parse()?;
+            input.parse::<Token![,]>()?;
+            let command_struct = input.parse()?;
+            input.parse::<Token![=>]>()?;
+            let pack = input.parse()?;
+
+            Ok(DispatcherChainInput::Explicit {
+                group_name,
+                command_name,
+                command_struct,
+                pack,
+            })
+        } else if lookahead.peek(syn::LitStr) {
+            // Default format: "command_name", CommandStruct => ChainStruct
+            let command_name = input.parse()?;
+            input.parse::<Token![,]>()?;
+            let command_struct = input.parse()?;
+            input.parse::<Token![=>]>()?;
+            let pack = input.parse()?;
+
+            Ok(DispatcherChainInput::Default {
+                command_name,
+                command_struct,
+                pack,
+            })
+        } else {
+            Err(lookahead.error())
+        }
+    }
+}
+
+// NOTICE: This implementation contains significant code duplication between the explicit
+// and default cases in both `dispatcher_chain` and `dispatcher_render` functions.
+// The logic for handling default vs explicit group names and generating the appropriate
+// code should be extracted into common helper functions to reduce redundancy.
+// Additionally, the token stream generation patterns are nearly identical between
+// the two main functions and could benefit from refactoring.
+
+pub fn dispatcher_chain(input: TokenStream) -> TokenStream {
+    // Parse the input
+    let dispatcher_input = syn::parse_macro_input!(input as DispatcherChainInput);
+
+    // Determine if we're using default or explicit group
+    let (group_name, command_name, command_struct, pack, use_default) = match dispatcher_input {
+        DispatcherChainInput::Explicit {
+            group_name,
+            command_name,
+            command_struct,
+            pack,
+        } => (group_name, command_name, command_struct, pack, false),
+        DispatcherChainInput::Default {
+            command_name,
+            command_struct,
+            pack,
+        } => (
+            Ident::new("ThisProgram", proc_macro2::Span::call_site()),
+            command_name,
+            command_struct,
+            pack,
+            true,
+        ),
+    };
+
+    let command_name_str = command_name.value();
+
+    let comp_entry = get_comp_entry(&pack);
+
+    let expanded = if use_default {
+        // For default case, use ThisProgram
+        quote! {
+            #[derive(Debug, Default)]
+            pub struct #command_struct;
+
+            ::mingling::macros::pack!(ThisProgram, #pack = Vec<String>);
+
+            #comp_entry
+
+            impl ::mingling::Dispatcher<ThisProgram> for #command_struct {
+                fn node(&self) -> ::mingling::Node {
+                    ::mingling::macros::node!(#command_name_str)
+                }
+                fn begin(&self, args: Vec<String>) -> ::mingling::ChainProcess<ThisProgram> {
+                    #pack::new(args).to_chain()
+                }
+                fn clone_dispatcher(&self) -> Box<dyn ::mingling::Dispatcher<ThisProgram>> {
+                    Box::new(#command_struct)
+                }
+            }
+        }
+    } else {
+        // For explicit case, use the provided group_name
+        quote! {
+            #[derive(Debug, Default)]
+            pub struct #command_struct;
+
+            ::mingling::macros::pack!(#group_name, #pack = Vec<String>);
+
+            #comp_entry
+
+            impl ::mingling::Dispatcher<#group_name> for #command_struct {
+                fn node(&self) -> ::mingling::Node {
+                    ::mingling::macros::node!(#command_name_str)
+                }
+                fn begin(&self, args: Vec<String>) -> ::mingling::ChainProcess<#group_name> {
+                    #pack::new(args).to_chain()
+                }
+                fn clone_dispatcher(&self) -> Box<dyn ::mingling::Dispatcher<#group_name>> {
+                    Box::new(#command_struct)
+                }
+            }
+        }
+    };
+
+    expanded.into()
+}
+
+#[cfg(feature = "comp")]
+fn get_comp_entry(entry_name: &Ident) -> proc_macro2::TokenStream {
+    let comp_entry = quote! {
+        impl ::mingling::CompletionEntry for #entry_name {
+            fn get_input(self) -> Vec<String> {
+                self.inner.clone()
+            }
+        }
+    };
+    comp_entry
+}
+
+#[cfg(not(feature = "comp"))]
+fn get_comp_entry(_entry_name: &Ident) -> proc_macro2::TokenStream {
+    quote! {}
+}