// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.

// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

// 	http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

use super::{Config, Kind, OffenceDetails, Pallet, Perbill, SessionIndex, LOG_TARGET};

use alloc::vec::Vec;

use frame_support::{

	pallet_prelude::ValueQuery,

	storage_alias,

	traits::{Get, GetStorageVersion, OnRuntimeUpgrade},

	weights::Weight,

	Twox64Concat,

};

use sp_staking::offence::OnOffenceHandler;

#[cfg(feature = "try-runtime")]

use frame_support::ensure;

#[cfg(feature = "try-runtime")]

use sp_runtime::TryRuntimeError;

mod v0 {

	use super::*;

	pub type ReportsByKindIndex<T: Config> = StorageMap<

		Pallet<T>,

		Twox64Concat,

		Kind,

		Vec<u8>, // (O::TimeSlot, ReportIdOf<T>)

		ValueQuery,

	>;

}

pub mod v1 {

	use frame_support::traits::StorageVersion;

	use super::*;

	pub struct MigrateToV1<T>(core::marker::PhantomData<T>);

	impl<T: Config> OnRuntimeUpgrade for MigrateToV1<T> {

		#[cfg(feature = "try-runtime")]

				target: LOG_TARGET,

			);

		#[cfg(feature = "try-runtime")]

			);

	}

}

/// Type of data stored as a deferred offence

type DeferredOffenceOf<T> = (

	Vec<OffenceDetails<<T as frame_system::Config>::AccountId, <T as Config>::IdentificationTuple>>,

	Vec<Perbill>,

	SessionIndex,

);

// Deferred reports that have been rejected by the offence handler and need to be submitted

// at a later time.

type DeferredOffences<T: Config> =

	StorageValue<crate::Pallet<T>, Vec<DeferredOffenceOf<T>>, ValueQuery>;

#[cfg(test)]

mod test {

	use super::*;

	use crate::mock::{new_test_ext, with_on_offence_fractions, Runtime as T, KIND};

	use codec::Encode;

	use sp_runtime::Perbill;

	use sp_staking::offence::OffenceDetails;

	#[test]

	fn migration_to_v1_works() {

		let mut ext = new_test_ext();

		ext.execute_with(|| {

			<v0::ReportsByKindIndex<T>>::insert(KIND, 2u32.encode());

			assert!(<v0::ReportsByKindIndex<T>>::iter_values().count() > 0);

		});

		ext.commit_all().unwrap();

		ext.execute_with(|| {

			assert_eq!(

				v1::MigrateToV1::<T>::on_runtime_upgrade(),

				<T as frame_system::Config>::DbWeight::get().reads_writes(2, 2),

			);

			assert!(<v0::ReportsByKindIndex<T>>::iter_values().count() == 0);

		})

	}

	#[test]

	fn should_resubmit_deferred_offences() {

		new_test_ext().execute_with(|| {

			// given

			assert_eq!(<DeferredOffences<T>>::get().len(), 0);

			with_on_offence_fractions(|f| {

				assert_eq!(f.clone(), vec![]);

			});

			let offence_details = OffenceDetails::<

				<T as frame_system::Config>::AccountId,

				<T as Config>::IdentificationTuple,

			> {

				offender: 5,

				reporters: vec![],

			};

			// push deferred offence

			<DeferredOffences<T>>::append((

				vec![offence_details],

				vec![Perbill::from_percent(5 + 1 * 100 / 5)],

				1,

			));

			// when

			assert_eq!(

				remove_deferred_storage::<T>(),

				<T as frame_system::Config>::DbWeight::get().reads_writes(1, 1),

			);

			// then

			assert!(!<DeferredOffences<T>>::exists());

			with_on_offence_fractions(|f| {

				assert_eq!(f.clone(), vec![Perbill::from_percent(5 + 1 * 100 / 5)]);

			});

		})

	}

}