mod ast_node;
mod build_fn;
mod deserialize;
mod pretty_print;
mod spec;
mod type_gen;
mod walk;

use crate::ast_node::{
    make_ast_enum_member, make_ast_enum_mut_member, make_ast_node_impl,
    make_ast_node_ref_mut_unwrapper, make_ast_node_ref_unwrapper,
};
use crate::build_fn::make_build_fn;
use crate::deserialize::deserialize_yaml_spec;
use crate::pretty_print::make_pretty_print_impl;
use crate::type_gen::make_type;
use crate::walk::make_walk_fn;
use proc_macro2::TokenStream;
use quote::quote;
use spec::BuildSpec;
use syn::File;

fn debug_built_spec(build_spec: &BuildSpec, token_stream: &TokenStream) {
    println!("*** BuildSpec ***");
    match build_spec {
        BuildSpec::Enum(enum_build_spec) => {
            println!("Enum Spec - build: {}", enum_build_spec.build());
        }
        BuildSpec::LeafEnum(leaf_enum_build_spec) => {
            println!("Leaf Enum Spec - build: {}", leaf_enum_build_spec.build());
        }
        BuildSpec::Struct(struct_build_spec) => {
            println!("Struct Spec - build: {}", struct_build_spec.build());
        }
        BuildSpec::LeafStruct(leaf_struct_build_spec) => {
            println!(
                "Leaf Struct Spec - build: {}",
                leaf_struct_build_spec.build()
            );
        }
        BuildSpec::Production(production_build_spec) => {
            println!("Production Spec - name: {}", production_build_spec.name());
        }
        BuildSpec::NodeProduction(node_production_build_spec) => {
            println!(
                "Node Production Spec - name: {}",
                node_production_build_spec.name()
            );
        }
        BuildSpec::PolymorphicType(polymorphic_build_spec) => {
            println!(
                "Polymorphic Type Spec - name: {}",
                polymorphic_build_spec.name()
            );
        }
        BuildSpec::PolymorphicEnumLoop(polymorphic_enum_loop_build_spec) => {
            println!(
                "Polymorphic Enum Loop Spec - name: {}",
                polymorphic_enum_loop_build_spec.name()
            );
        }
        BuildSpec::PolymorphicPassThrough(pass_through_build_spec) => {
            println!(
                "Polymorphic Pass Through Spec - name: {}",
                pass_through_build_spec.name()
            );
        }
        BuildSpec::PolymorphicEnumInnerBuild(polymorphic_enum_inner_build_spec) => {
            println!(
                "Polymorphic Enum Inner Build Spec - name: {}",
                polymorphic_enum_inner_build_spec.name()
            );
        }
        BuildSpec::PolymorphicLeafEnum(polymorphic_leaf_enum) => {
            println!(
                "Polymorphic Leaf Enum Build Spec - name: {}",
                polymorphic_leaf_enum.name()
            );
        }
        BuildSpec::PolymorphicTreeEnum(polymorphic_tree_enum) => {
            println!(
                "Polymorphic Tree Enum Build Spec - name: {}",
                polymorphic_tree_enum.name()
            );
        }
    }
    println!("{:#?}", token_stream);
    let parsed: File = syn::parse2(token_stream.clone()).unwrap();
    println!("{}", prettyplease::unparse(&parsed));
}

pub struct AstGeneratedFile {
    pub name: String,
    pub contents: String,
}

fn token_stream_to_string(token_stream: TokenStream) -> String {
    let file: File = syn::parse2(token_stream).unwrap();
    prettyplease::unparse(&file)
}

fn generate_build_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
    let build_fns = build_specs
        .iter()
        .map(|build_spec| {
            let build_fn = make_build_fn(build_spec);
            debug_built_spec(build_spec, &build_fn);
            build_fn
        })
        .collect::<Vec<_>>();

    let combined = quote! {
        use crate::parser::Rule;
        use pest::iterators::Pair;
        use crate::ast::node::*;
        use std::range::Range;

        #(#build_fns)*
    };

    AstGeneratedFile {
        name: String::from("build.rs"),
        contents: token_stream_to_string(combined),
    }
}

fn generate_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
    let types = build_specs
        .iter()
        .map(|build_spec| make_type(build_spec))
        .filter(Option::is_some)
        .collect::<Vec<_>>();
    let combined = quote! {
        use std::range::Range;
        use std::rc::Rc;
        use std::cell::RefCell;
        use crate::name_analysis::symbol::*;
        use crate::type_analysis::kinds::*;

        #(#types)*
    };
    AstGeneratedFile {
        name: String::from("node.rs"),
        contents: token_stream_to_string(combined),
    }
}

fn generate_pretty_print_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
    let impls = build_specs
        .iter()
        .map(|build_spec| {
            let maybe_stream = make_pretty_print_impl(build_spec);
            if let Some(stream) = &maybe_stream {
                debug_built_spec(build_spec, &stream);
            }
            maybe_stream
        })
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let combined = quote! {
        use crate::ast::node::*;
        #(#impls)*
    };
    AstGeneratedFile {
        name: String::from("pretty_print.rs"),
        contents: token_stream_to_string(combined),
    }
}

fn generate_ast_node_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
    let impls = build_specs
        .iter()
        .map(|build_spec| {
            let maybe_stream = make_ast_node_impl(build_spec);
            if let Some(stream) = &maybe_stream {
                debug_built_spec(build_spec, &stream);
            }
            maybe_stream
        })
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let ast_enum_members = build_specs
        .iter()
        .map(|build_spec| make_ast_enum_member(build_spec))
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let ast_enum_mut_members = build_specs
        .iter()
        .map(|build_spec| make_ast_enum_mut_member(build_spec))
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let inner_unwrappers = build_specs
        .iter()
        .map(|build_spec| make_ast_node_ref_unwrapper(build_spec))
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let inner_mut_unwrappers = build_specs
        .iter()
        .map(|build_spec| make_ast_node_ref_mut_unwrapper(build_spec))
        .filter(Option::is_some)
        .map(Option::unwrap)
        .collect::<Vec<_>>();

    let combined = quote! {
        use crate::ast::node::*;

        pub enum AstNodeRef<'a> {
            #(#ast_enum_members,)*
        }

        impl<'a> AstNodeRef<'a> {
            pub fn inner(&self) -> &dyn AstNode<'a> {
                match self {
                    #(#inner_unwrappers,)*
                }
            }
        }

        pub enum AstNodeRefMut<'a> {
            #(#ast_enum_mut_members,)*
        }

        impl<'a> AstNodeRefMut<'a> {
            pub fn inner(&mut self) -> &mut dyn AstNode<'a> {
                match self {
                    #(#inner_mut_unwrappers,)*
                }
            }
        }

        pub trait AstNode<'a> {
            fn children(&'a self) -> Vec<&'a dyn AstNode<'a>>;

            fn for_each_child_mut(&'a mut self, f: &mut dyn FnMut(&'a mut dyn AstNode<'a>));

            fn as_node_ref(&'a self) -> AstNodeRef<'a>;

            fn as_node_ref_mut(&'a mut self) -> AstNodeRefMut<'a>;
        }

        #(#impls)*
    };
    AstGeneratedFile {
        name: String::from("ast_node.rs"),
        contents: token_stream_to_string(combined),
    }
}

fn generate_walk_file(build_specs: &[BuildSpec]) -> AstGeneratedFile {
    let stream = make_walk_fn(build_specs);
    AstGeneratedFile {
        name: String::from("walk.rs"),
        contents: token_stream_to_string(stream),
    }
}

pub fn get_build_specs(yaml: &str) -> Vec<BuildSpec> {
    deserialize_yaml_spec(yaml)
}

pub fn generate_files(build_specs: &[BuildSpec]) -> Vec<AstGeneratedFile> {
    vec![
        generate_build_file(build_specs),
        generate_node_file(build_specs),
        generate_pretty_print_file(build_specs),
        generate_ast_node_file(build_specs),
        generate_walk_file(build_specs),
    ]
}