#[cfg(not(windows))]
use std::env;

use crate::{
    AnyOutput, GlobalResources, asset::dispatcher::Dispatcher, error::ChainProcessError,
    hook::ProgramHook,
};
use std::{
    collections::HashMap,
    sync::{Arc, Mutex},
};

#[doc(hidden)]
pub mod error;
#[doc(hidden)]
pub mod exec;
#[doc(hidden)]
pub mod hook;
#[doc(hidden)]
pub mod setup;

mod collection;
pub use collection::*;

mod once_exec;

#[cfg(feature = "repl")]
mod repl_exec;
#[cfg(feature = "repl")]
pub use repl_exec::*;

mod single_instance;
pub use single_instance::*;

mod config;
pub use config::*;

mod flag;
pub use flag::*;

mod string_vec;
pub use string_vec::*;

/// Program, used to define the behavior of the entire command-line program
#[derive(Default)]
pub struct Program<C>
where
    C: ProgramCollect<Enum = C>,
{
    pub(crate) collect: std::marker::PhantomData<C>,

    pub(crate) args: Vec<String>,

    #[cfg(not(feature = "dispatch_tree"))]
    pub(crate) dispatcher: Vec<Box<dyn Dispatcher<C> + Send + Sync>>,

    pub stdout_setting: ProgramStdoutSetting,
    pub user_context: ProgramUserContext,

    #[cfg(feature = "general_renderer")]
    pub general_renderer_name: GeneralRendererSetting,

    pub(crate) hooks: Vec<ProgramHook<C>>,

    pub(crate) resources: GlobalResources,
}

impl<C> Program<C>
where
    C: ProgramCollect<Enum = C>,
{
    /// Creates a new Program instance, initializing command-line arguments from the environment.
    pub fn new() -> Self {
        #[cfg(not(windows))]
        return Self::new_with_args(env::args().collect::<Vec<String>>());

        #[cfg(windows)]
        return Self::new_with_args({
            std::env::args_os()
                .map(|arg| {
                    use std::os::windows::ffi::OsStrExt;

                    let wide: Vec<u16> = arg.encode_wide().collect();
                    String::from_utf16_lossy(&wide)
                })
                .collect::<Vec<_>>()
        });
    }

    /// Creates a new Program instance with the provided command-line arguments.
    pub fn new_with_args(args: impl Into<StringVec>) -> Self {
        Program {
            collect: std::marker::PhantomData,
            args: args.into().into(),

            #[cfg(not(feature = "dispatch_tree"))]
            dispatcher: Vec::new(),

            stdout_setting: Default::default(),
            user_context: Default::default(),

            #[cfg(feature = "general_renderer")]
            general_renderer_name: GeneralRendererSetting::Disable,

            hooks: Vec::new(),

            resources: Arc::new(Mutex::new(HashMap::new())),
        }
    }

    /// Returns a reference to the current program instance, if set.
    pub fn this_program() -> &'static Program<C>
    where
        C: 'static,
    {
        THIS_PROGRAM
            .get()
            .unwrap()
            .as_ref()
            .unwrap()
            .downcast_ref::<Program<C>>()
            .unwrap()
    }

    /// Get all registered dispatcher names from the program
    pub fn get_nodes(
        &'static self,
    ) -> Vec<(String, &'static (dyn Dispatcher<C> + Send + Sync + 'static))> {
        get_nodes(self)
    }

    /// Dynamically dispatch input arguments to registered entry types
    pub fn dispatch_args_dynamic(
        &'static self,
        args: impl Into<StringVec>,
    ) -> Result<AnyOutput<C>, ChainProcessError> {
        match exec::dispatch_args_dynamic(self, &args.into().into()) {
            Ok(ok) => Ok(ok),
            Err(e) => Err(e.into()),
        }
    }

    /// Use a prefix tree to quickly match arguments and dispatch to an Entry
    #[cfg(feature = "dispatch_tree")]
    pub fn dispatch_args_trie(
        &'static self,
        args: impl Into<StringVec>,
    ) -> Result<AnyOutput<C>, ChainProcessError> {
        let string_vec: Vec<String> = args.into().into();
        match C::dispatch_args_trie(&string_vec) {
            Ok(ok) => Ok(ok),
            Err(e) => Err(e.into()),
        }
    }
}

#[macro_export]
#[doc(hidden)]
macro_rules! __dispatch_program_renderers {
    (
        $( $render_ty:ty => $prev_ty:ident, )*
    ) => {
        fn render(any: mingling::AnyOutput<Self::Enum>, r: &mut mingling::RenderResult) {
            match any.member_id {
                $(
                    Self::$prev_ty => {
                        // SAFETY: The `type_id` check ensures that `any` contains a value of type `$prev_ty`,
                        // so downcasting to `$prev_ty` is safe.
                        let value = unsafe { any.downcast::<$prev_ty>().unwrap_unchecked() };
                        <$render_ty as mingling::Renderer>::render(value, r);
                    }
                )*
                _ => (),
            }
        }
    };
}

#[macro_export]
#[doc(hidden)]
#[cfg(feature = "async")]
macro_rules! __dispatch_program_chains {
    (
        $( $chain_ty:ty => $chain_prev:ident, )*
    ) => {
        fn do_chain(
            any: mingling::AnyOutput<Self::Enum>,
        ) -> std::pin::Pin<Box<dyn Future<Output = mingling::ChainProcess<Self::Enum>> + Send>> {
            match any.member_id {
                $(
                    Self::$chain_prev => {
                        // SAFETY: The `type_id` check ensures that `any` contains a value of type `$chain_prev`,
                        // so downcasting to `$chain_prev` is safe.
                        let value = unsafe { any.downcast::<$chain_prev>().unwrap_unchecked() };
                        let fut = async { <$chain_ty as mingling::Chain<Self::Enum>>::proc(value).await };
                        Box::pin(fut)
                    }
                )*
                _ => panic!("No chain found for type id: {:?}", any.type_id),
            }
        }
    };
}

#[macro_export]
#[doc(hidden)]
#[cfg(not(feature = "async"))]
macro_rules! __dispatch_program_chains {
    (
        $( $chain_ty:ty => $chain_prev:ident, )*
    ) => {
        fn do_chain(
            any: mingling::AnyOutput<Self::Enum>,
        ) -> mingling::ChainProcess<Self::Enum> {
            match any.member_id {
                $(
                    Self::$chain_prev => {
                        // SAFETY: The `type_id` check ensures that `any` contains a value of type `$chain_prev`,
                        // so downcasting to `$chain_prev` is safe.
                        let value = unsafe { any.downcast::<$chain_prev>().unwrap_unchecked() };
                        <$chain_ty as mingling::Chain<Self::Enum>>::proc(value)
                    }
                )*
                _ => panic!("No chain found for type id: {:?}", any.type_id),
            }
        }
    };
}

/// Get all registered dispatcher names from the program
#[allow(unused_variables)]
pub fn get_nodes<C: ProgramCollect<Enum = C>>(
    program: &'static Program<C>,
) -> Vec<(String, &'static (dyn Dispatcher<C> + Send + Sync + 'static))> {
    #[cfg(feature = "dispatch_tree")]
    let r = C::get_nodes();

    #[cfg(feature = "dispatch_tree")]
    {
        #[cfg(feature = "debug")]
        {
            let node_strs: Vec<String> = r.iter().map(|v| v.0.clone()).collect();
            crate::info!("All Nodes: [{}]", node_strs.join(", "));
        }
    }

    #[cfg(not(feature = "dispatch_tree"))]
    let r: Vec<_> = program
        .dispatcher
        .iter()
        .map(|disp| {
            let node_str = disp
                .node()
                .to_string()
                .split('.')
                .collect::<Vec<_>>()
                .join(" ");
            (node_str, &**disp)
        })
        .collect();

    #[cfg(not(feature = "dispatch_tree"))]
    {
        #[cfg(feature = "debug")]
        {
            let node_strs: Vec<String> = r.iter().map(|v| v.0.clone()).collect();
            crate::info!("All Nodes: [{}]", node_strs.join(", "));
        }
    }

    r
}