use crate::error::Error;

use clap::*;
use serde::{Deserialize, Serialize};
use sp_npos_elections::BalancingConfig;
use sp_runtime::DeserializeOwned;

use std::{collections::HashMap, fmt, str::FromStr};
use subxt::backend::legacy::rpc_methods:: as subxt_rpc;

#[derive(Debug, Clone, Parser)]
#[cfg_attr(test, derive(PartialEq))]
pub enum Solver {
    SeqPhragmen {
        #[clap(long, default_value = "10")]
        iterations: usize,
    },
    PhragMMS {
        #[clap(long, default_value = "10")]
        iterations: usize,
    }
}

frame_support::parameter_types! {
    pub static BalanceIterations: usize = 10;
    pub static Balancing: Option<BalancingConfig> =
        Some(BalancingConfig { iterations: BalanceIterations::get(), tolerance: 0 });
}

#[derive(Debug, Copy, Clone)]
pub enum Chain {
    Ghost,
    Casper
}

impl fmt::Display for Chain {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let chain = match self {
            Self::Ghost => "ghost",
            Self::Casper => "casper",
        };
        write!(f, "{}", chain)
    }
}

impl std::str::FromStr for Chain {
    type Err = Error;

    fn from_str(s: &str) -> Result<Self, Error> {
        match s {
            "ghost" => Ok(Self::Ghost),
            "casper" => Ok(Self::Casper),
            chain => Err(Error::InvalidChain(chain.to_string())),
        }
    }
}

impl TryFrom<subxt_rpc::RuntimeVersion> for Chain {
    type Error = Error;

    fn try_from(rv: subxt_rpc::RuntimeVersion) -> Result<Self, Error> {
        let json = rv
            .other
            .get("specName")
            .expect("RuntimeVersion must have specName; qed")
            .clone();
        let mut chain = serde_json::from_value::<String>(json)
            .expect("specName must be String; qed");
        chain.make_ascii_lowercase();
        Chain::from_str(&chain)
    }
}

impl From<subxt_rpc::RuntimeVersion> for RuntimeVersion {
    fn from(rv: subxt_rpc::RuntimeVersion) -> Self {
        let mut spec_name: String = get_val_unchecked("specName", &rv.other);
        let impl_name: String = get_val_unchecked("implName", &rv.other);
        let impl_version: u32 = get_val_unchecked("implVersion", &rv.other);
        let authoring_version: u32 = get_val_unchecked("authoringVersion", &rv.other);
        let state_version: u32 = get_val_unchecked("stateVersion", &rv.other);

        let spec_version = rv.spec_version;
        let transaction_version = rv.transaction_version;

        spec_name.make_ascii_lowercase();

        Self {
            spec_name,
            impl_name,
            impl_version,
            spec_version,
            transaction_version,
            authoring_version,
            state_version,
        }
    }
}

#[derive(Deserialize, Serialize, PartialEq, Debug, Clone)]
#[derive(Debug)]
pub struct RuntimeVersion {
    pub spec_name: String,
    pub impl_name: String,
    pub spec_version: u32,
    pub impl_version: u32,
    pub authoring_version: u32,
    pub transaction_version: u32,
    pub state_version: u8,
}

fn get_val_unchecked<T: DeserializeOwned>(val: &str, rv: &HashMap<String, serde_json::Value>) -> T {
    let json = rv.get(val).expect("`{val}` must exist; qed").clone();
    serde_json::from_value::<T>(json).expect("T must be Deserialize; qed")
}