// Copyright 2015-2018 Parity Technologies (UK) Ltd.
// This file is part of Parity.

// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Parity.  If not, see <http://www.gnu.org/licenses/>.

//! General test deserialization.

use std::io::Read;
use std::collections::BTreeMap;
use uint::Uint;
use bytes::Bytes;
use hash::{Address, H256};
use state::{Env, AccountState, Transaction};
use maybe::MaybeEmpty;
use serde_json::{self, Error};

/// State test deserializer.
#[derive(Debug, PartialEq, Deserialize)]
pub struct Test(BTreeMap<String, State>);

impl IntoIterator for Test {
	type Item = <BTreeMap<String, State> as IntoIterator>::Item;
	type IntoIter = <BTreeMap<String, State> as IntoIterator>::IntoIter;

	fn into_iter(self) -> Self::IntoIter {
		self.0.into_iter()
	}
}

impl Test {
	/// Loads test from json.
	pub fn load<R>(reader: R) -> Result<Self, Error> where R: Read {
		serde_json::from_reader(reader)
	}
}

/// State test deserialization.
#[derive(Debug, PartialEq, Deserialize)]
pub struct State {
	/// Environment.
	pub env: Env,
	/// Pre state.
	#[serde(rename="pre")]
	pub pre_state: AccountState,
	/// Post state.
	#[serde(rename="post")]
	pub post_states: BTreeMap<ForkSpec, Vec<PostStateResult>>,
	/// Transaction.
	pub transaction: MultiTransaction,
}

/// State test transaction deserialization.
#[derive(Debug, PartialEq, Deserialize)]
pub struct MultiTransaction {
	/// Transaction data set.
	pub data: Vec<Bytes>,
	/// Gas limit set.
	#[serde(rename="gasLimit")]
	pub gas_limit: Vec<Uint>,
	/// Gas price.
	#[serde(rename="gasPrice")]
	pub gas_price: Uint,
	/// Nonce.
	pub nonce: Uint,
	/// Secret key.
	#[serde(rename="secretKey")]
	pub secret: Option<H256>,
	/// To.
	pub to: MaybeEmpty<Address>,
	/// Value set.
	pub value: Vec<Uint>,
}

impl MultiTransaction {
	/// Build transaction with given indexes.
	pub fn select(&self, indexes: &PostStateIndexes) -> Transaction {
		Transaction {
			data: self.data[indexes.data as usize].clone(),
			gas_limit: self.gas_limit[indexes.gas as usize].clone(),
			gas_price: self.gas_price.clone(),
			nonce: self.nonce.clone(),
			secret: self.secret.clone(),
			to: self.to.clone(),
			value: self.value[indexes.value as usize].clone(),
		}
	}
}

/// State test transaction deserialization.
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Deserialize)]
pub enum ForkSpec {
	EIP150,
	EIP158,
	Frontier,
	Homestead,
	Byzantium,
	Constantinople,
	EIP158ToByzantiumAt5,
	FrontierToHomesteadAt5,
	HomesteadToDaoAt5,
	HomesteadToEIP150At5,
}

/// State test indexes deserialization.
#[derive(Debug, PartialEq, Deserialize)]
pub struct PostStateIndexes {
	/// Index into transaction data set.
	pub data: u64,
	/// Index into transaction gas limit set.
	pub gas: u64,
	/// Index into transaction value set.
	pub value: u64,
}

/// State test indexed state result deserialization.
#[derive(Debug, PartialEq, Deserialize)]
pub struct PostStateResult {
	/// Post state hash
	pub hash: H256,
	/// Indexes
	pub indexes: PostStateIndexes,
}

#[cfg(test)]
mod tests {
	use serde_json;
	use super::{MultiTransaction, State};

	#[test]
	fn multi_transaction_deserialization() {
		let s = r#"{
			"data" : [ "" ],
			"gasLimit" : [ "0x2dc6c0", "0x222222" ],
			"gasPrice" : "0x01",
			"nonce" : "0x00",
			"secretKey" : "45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8",
			"to" : "1000000000000000000000000000000000000000",
			"value" : [ "0x00", "0x01", "0x02" ]
		}"#;
		let _deserialized: MultiTransaction = serde_json::from_str(s).unwrap();
	}

	#[test]
	fn state_deserialization() {
		let s = r#"{
			"env" : {
				"currentCoinbase" : "2adc25665018aa1fe0e6bc666dac8fc2697ff9ba",
				"currentDifficulty" : "0x0100",
				"currentGasLimit" : "0x01c9c380",
				"currentNumber" : "0x00",
				"currentTimestamp" : "0x01",
				"previousHash" : "5e20a0453cecd065ea59c37ac63e079ee08998b6045136a8ce6635c7912ec0b6"
			},
			"post" : {
				"EIP150" : [
					{
						"hash" : "3e6dacc1575c6a8c76422255eca03529bbf4c0dda75dfc110b22d6dc4152396f",
						"indexes" : { "data" : 0, "gas" : 0,  "value" : 0 }
					},
					{
						"hash" : "99a450d8ce5b987a71346d8a0a1203711f770745c7ef326912e46761f14cd764",
						"indexes" : { "data" : 0, "gas" : 0,  "value" : 1 }
					}
				],
				"EIP158" : [
					{
						"hash" : "3e6dacc1575c6a8c76422255eca03529bbf4c0dda75dfc110b22d6dc4152396f",
						"indexes" : { "data" : 0,   "gas" : 0,  "value" : 0 }
					},
					{
						"hash" : "99a450d8ce5b987a71346d8a0a1203711f770745c7ef326912e46761f14cd764",
						"indexes" : { "data" : 0,   "gas" : 0,  "value" : 1  }
					}
				]
			},
			"pre" : {
				"1000000000000000000000000000000000000000" : {
					"balance" : "0x0de0b6b3a7640000",
					"code" : "0x6040600060406000600173100000000000000000000000000000000000000162055730f1600055",
					"nonce" : "0x00",
					"storage" : {
					}
				},
				"1000000000000000000000000000000000000001" : {
					"balance" : "0x0de0b6b3a7640000",
					"code" : "0x604060006040600060027310000000000000000000000000000000000000026203d090f1600155",
					"nonce" : "0x00",
					"storage" : {
					}
				},
				"1000000000000000000000000000000000000002" : {
					"balance" : "0x00",
					"code" : "0x600160025533600455346007553060e6553260e8553660ec553860ee553a60f055",
					"nonce" : "0x00",
					"storage" : {
					}
				},
				"a94f5374fce5edbc8e2a8697c15331677e6ebf0b" : {
					"balance" : "0x0de0b6b3a7640000",
					"code" : "0x",
					"nonce" : "0x00",
					"storage" : {
					}
				}
			},
			"transaction" : {
				"data" : [ "" ],
				"gasLimit" : [ "285000",   "100000",  "6000" ],
				"gasPrice" : "0x01",
				"nonce" : "0x00",
				"secretKey" : "45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8",
				"to" : "095e7baea6a6c7c4c2dfeb977efac326af552d87",
				"value" : [   "10",   "0" ]
			}
		}"#;
		let _deserialized: State = serde_json::from_str(s).unwrap();
		// TODO: validate all fields
	}
}