// 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.

//! Integration tests for runtime interface primitives
#![cfg(test)]

use sp_runtime_interface::*;

use sp_runtime_interface_test_wasm::{test_api::HostFunctions, wasm_binary_unwrap};
use sp_runtime_interface_test_wasm_deprecated::wasm_binary_unwrap as wasm_binary_deprecated_unwrap;

use sc_executor_common::{runtime_blob::RuntimeBlob, wasm_runtime::AllocationStats};
use sp_wasm_interface::{ExtendedHostFunctions, HostFunctions as HostFunctionsT};

use std::{
	collections::HashSet,
	sync::{Arc, Mutex},
};

type TestExternalities = sp_state_machine::TestExternalities<sp_runtime::traits::BlakeTwo256>;

fn call_wasm_method_with_result<HF: HostFunctionsT>(
	binary: &[u8],
	method: &str,
) -> (Result<TestExternalities, String>, Option<AllocationStats>) {
	let mut ext = TestExternalities::default();
	let mut ext_ext = ext.ext();

	let executor = sc_executor::WasmExecutor::<
		ExtendedHostFunctions<sp_io::SubstrateHostFunctions, HF>,
	>::new(sc_executor::WasmExecutionMethod::Interpreted, Some(8), 8, None, 2);

	let (result, allocation_stats) = executor.uncached_call_with_allocation_stats(
		RuntimeBlob::uncompress_if_needed(binary).expect("Failed to parse binary"),
		&mut ext_ext,
		false,
		method,
		&[],
	);
	let result = result
		.map_err(|e| format!("Failed to execute `{}`: {}", method, e))
		.map(|_| ext);
	(result, allocation_stats)
}

fn call_wasm_method<HF: HostFunctionsT>(binary: &[u8], method: &str) -> TestExternalities {
	call_wasm_method_with_result::<HF>(binary, method).0.unwrap()
}

#[test]
fn test_return_data() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_return_data");
}

#[test]
fn test_return_option_data() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_return_option_data");
}

#[test]
fn test_set_storage() {
	let mut ext = call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_set_storage");

	let expected = "world";
	assert_eq!(expected.as_bytes(), &ext.ext().storage("hello".as_bytes()).unwrap()[..]);
}

#[test]
fn test_return_value_into_mutable_reference() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_return_value_into_mutable_reference",
	);
}

#[test]
fn test_get_and_return_array() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_get_and_return_array");
}

#[test]
fn test_array_as_mutable_reference() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_array_as_mutable_reference");
}

#[test]
fn test_return_input_public_key() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_return_input_public_key");
}

#[test]
fn host_function_not_found() {
	let err = call_wasm_method_with_result::<()>(wasm_binary_unwrap(), "test_return_data")
		.0
		.unwrap_err();

	assert!(err.contains("Instantiation: Export "));
	assert!(err.contains(" not found"));
}

#[test]
#[should_panic(expected = "Invalid utf8 data provided")]
fn test_invalid_utf8_data_should_return_an_error() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_invalid_utf8_data_should_return_an_error",
	);
}

#[test]
fn test_overwrite_native_function_implementation() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_overwrite_native_function_implementation",
	);
}

#[test]
fn test_u128_i128_as_parameter_and_return_value() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_u128_i128_as_parameter_and_return_value",
	);
}

#[test]
fn test_vec_return_value_memory_is_freed() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_vec_return_value_memory_is_freed",
	);
}

#[test]
fn test_encoded_return_value_memory_is_freed() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_encoded_return_value_memory_is_freed",
	);
}

#[test]
fn test_array_return_value_memory_is_freed() {
	call_wasm_method::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_array_return_value_memory_is_freed",
	);
}

#[test]
fn test_versionining_with_new_host_works() {
	// We call to the new wasm binary with new host function.
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_versionning_works");

	// we call to the old wasm binary with a new host functions
	// old versions of host functions should be called and test should be ok!
	call_wasm_method::<HostFunctions>(wasm_binary_deprecated_unwrap(), "test_versionning_works");
}

#[test]
fn test_versionining_register_only() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_versionning_register_only_works");
}

#[test]
fn test_tracing() {
	use std::fmt;
	use tracing::span::Id as SpanId;
	use tracing_core::field::{Field, Visit};

	#[derive(Clone)]
	struct TracingSubscriber(Arc<Mutex<Inner>>);

	struct FieldConsumer(&'static str, Option<String>);
	impl Visit for FieldConsumer {
		fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
			if field.name() == self.0 {
				self.1 = Some(format!("{:?}", value))
			}
		}
	}

	#[derive(Default)]
	struct Inner {
		spans: HashSet<String>,
	}

	impl tracing::subscriber::Subscriber for TracingSubscriber {
		fn enabled(&self, _: &tracing::Metadata) -> bool {
			true
		}

		fn new_span(&self, span: &tracing::span::Attributes) -> tracing::Id {
			let mut inner = self.0.lock().unwrap();
			let id = SpanId::from_u64((inner.spans.len() + 1) as _);
			let mut f = FieldConsumer("name", None);
			span.record(&mut f);
			inner.spans.insert(f.1.unwrap_or_else(|| span.metadata().name().to_owned()));
			id
		}

		fn record(&self, _: &SpanId, _: &tracing::span::Record) {}

		fn record_follows_from(&self, _: &SpanId, _: &SpanId) {}

		fn event(&self, _: &tracing::Event) {}

		fn enter(&self, _: &SpanId) {}

		fn exit(&self, _: &SpanId) {}
	}

	let subscriber = TracingSubscriber(Default::default());
	let _guard = tracing::subscriber::set_default(subscriber.clone());

	// Call some method to generate a trace
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_return_data");

	let inner = subscriber.0.lock().unwrap();
	assert!(inner.spans.contains("return_input_version_1"));
}

#[test]
fn test_return_input_as_tuple() {
	call_wasm_method::<HostFunctions>(wasm_binary_unwrap(), "test_return_input_as_tuple");
}

#[test]
fn test_returning_option_bytes_from_a_host_function_is_efficient() {
	let (result, stats_vec) = call_wasm_method_with_result::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_return_option_vec",
	);
	result.unwrap();
	let (result, stats_bytes) = call_wasm_method_with_result::<HostFunctions>(
		wasm_binary_unwrap(),
		"test_return_option_bytes",
	);
	result.unwrap();

	let stats_vec = stats_vec.unwrap();
	let stats_bytes = stats_bytes.unwrap();

	// The way we currently implement marshaling of `Option<Vec<u8>>` through
	// the WASM FFI boundary from the host to the runtime requires that it is
	// marshaled through SCALE. This is quite inefficient as it requires two
	// memory allocations inside of the runtime:
	//
	//   1) the first allocation to copy the SCALE-encoded blob into the runtime;
	//   2) and another allocation for the resulting `Vec<u8>` when decoding that blob.
	//
	// Both of these allocations are are as big as the `Vec<u8>` which is being
	// passed to the runtime. This is especially bad when fetching big values
	// from storage, as it can lead to an out-of-memory situation.
	//
	// Our `Option<Bytes>` marshaling is better; it still must go through SCALE,
	// and it still requires two allocations, however since `Bytes` is zero-copy
	// only the first allocation is `Vec<u8>`-sized, and the second allocation
	// which creates the deserialized `Bytes` is tiny, and is only necessary because
	// the underlying `Bytes` buffer from which we're deserializing gets automatically
	// turned into an `Arc`.
	//
	// So this assertion tests that deserializing `Option<Bytes>` allocates less than
	// deserializing `Option<Vec<u8>>`.
	assert_eq!(stats_bytes.bytes_allocated_sum + 16 * 1024 + 8, stats_vec.bytes_allocated_sum);
}