//------------------------------------------------------------------------------
/*
    This file is part of clio: https://github.com/XRPLF/clio
    Copyright (c) 2023, the clio developers.

    Permission to use, copy, modify, and distribute this software for any
    purpose with or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.

    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================

#include "rpc/Counters.hpp"
#include "rpc/JS.hpp"
#include "rpc/WorkQueue.hpp"
#include "util/MockPrometheus.hpp"
#include "util/prometheus/Counter.hpp"
#include "util/prometheus/Histogram.hpp"

#include <boost/json/object.hpp>
#include <boost/json/value_to.hpp>
#include <gmock/gmock.h>
#include <gtest/gtest.h>
#include <xrpl/protocol/jss.h>

#include <chrono>
#include <cstdint>
#include <string>

using namespace rpc;

using util::prometheus::CounterInt;
using util::prometheus::WithMockPrometheus;
using util::prometheus::WithPrometheus;

struct RPCCountersBaseTest {
    struct WorkQueueMock : Reportable {
        MOCK_METHOD(boost::json::object, report, (), (const, override));
    };
    testing::StrictMock<WorkQueueMock> workQueueMock;
};

struct RPCCountersTest : WithPrometheus, RPCCountersBaseTest {
    Counters counters{workQueueMock};
};

TEST_F(RPCCountersTest, CheckThatCountersAddUp)
{
    for (auto i = 0u; i < 512u; ++i) {
        counters.rpcErrored("error");
        counters.rpcComplete("complete", std::chrono::milliseconds{1u});
        counters.rpcForwarded("forward");
        counters.rpcFailedToForward("failedToForward");
        counters.rpcFailed("failed");
        counters.onTooBusy();
        counters.onNotReady();
        counters.onBadSyntax();
        counters.onUnknownCommand();
        counters.onInternalError();
    }

    EXPECT_CALL(workQueueMock, report);
    auto const report = counters.report();
    auto const& rpc = report.at(JS(rpc)).as_object();

    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("error").as_object().at(JS(started))), "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("error").as_object().at(JS(finished))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("error").as_object().at(JS(errored))), "512"
    );
    EXPECT_EQ(boost::json::value_to<std::string>(rpc.at("error").as_object().at("forwarded")), "0");
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("error").as_object().at("failed_forward")), "0"
    );
    EXPECT_EQ(boost::json::value_to<std::string>(rpc.at("error").as_object().at(JS(failed))), "0");

    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at(JS(started))), "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at(JS(finished))), "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at(JS(errored))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at("forwarded")), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at("failed_forward")), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at(JS(failed))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("complete").as_object().at(JS(duration_us))),
        "512000"
    );  // 1000 per call

    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at(JS(started))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at(JS(finished))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at(JS(errored))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at("forwarded")), "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at("failed_forward")), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("forward").as_object().at(JS(failed))), "0"
    );

    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at(JS(started))), "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at(JS(finished))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at(JS(errored))), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at("forwarded")), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at("failed_forward")), "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failed").as_object().at(JS(failed))), "512"
    );

    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failedToForward").as_object().at(JS(started))),
        "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failedToForward").as_object().at(JS(finished))),
        "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failedToForward").as_object().at(JS(errored))),
        "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failedToForward").as_object().at("forwarded")),
        "0"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(
            rpc.at("failedToForward").as_object().at("failed_forward")
        ),
        "512"
    );
    EXPECT_EQ(
        boost::json::value_to<std::string>(rpc.at("failedToForward").as_object().at(JS(failed))),
        "0"
    );

    EXPECT_EQ(boost::json::value_to<std::string>(report.at("too_busy_errors")), "512");
    EXPECT_EQ(boost::json::value_to<std::string>(report.at("not_ready_errors")), "512");
    EXPECT_EQ(boost::json::value_to<std::string>(report.at("bad_syntax_errors")), "512");
    EXPECT_EQ(boost::json::value_to<std::string>(report.at("unknown_command_errors")), "512");
    EXPECT_EQ(boost::json::value_to<std::string>(report.at("internal_errors")), "512");
}

struct RPCCountersMockPrometheusTests : WithMockPrometheus, RPCCountersBaseTest {
    Counters counters{workQueueMock};
};

TEST_F(RPCCountersMockPrometheusTests, rpcFailed)
{
    auto& startedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"started\"}");
    auto& failedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"failed\"}");
    EXPECT_CALL(startedMock, add(1));
    EXPECT_CALL(failedMock, add(1));
    counters.rpcFailed("test");
}

TEST_F(RPCCountersMockPrometheusTests, rpcErrored)
{
    auto& startedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"started\"}");
    auto& erroredMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"errored\"}");
    EXPECT_CALL(startedMock, add(1));
    EXPECT_CALL(erroredMock, add(1));
    counters.rpcErrored("test");
}

TEST_F(RPCCountersMockPrometheusTests, rpcComplete)
{
    auto& startedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"started\"}");
    auto& finishedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"finished\"}");
    auto& durationMock = makeMock<CounterInt>("rpc_method_duration_us", "{method=\"test\"}");
    EXPECT_CALL(startedMock, add(1));
    EXPECT_CALL(finishedMock, add(1));
    EXPECT_CALL(durationMock, add(123));
    counters.rpcComplete("test", std::chrono::microseconds(123));
}

TEST_F(RPCCountersMockPrometheusTests, rpcForwarded)
{
    auto& forwardedMock =
        makeMock<CounterInt>("rpc_method_total_number", "{method=\"test\",status=\"forwarded\"}");
    EXPECT_CALL(forwardedMock, add(1));
    counters.rpcForwarded("test");
}

TEST_F(RPCCountersMockPrometheusTests, rpcFailedToForwarded)
{
    auto& failedForwardMock = makeMock<CounterInt>(
        "rpc_method_total_number", "{method=\"test\",status=\"failed_forward\"}"
    );
    EXPECT_CALL(failedForwardMock, add(1));
    counters.rpcFailedToForward("test");
}

TEST_F(RPCCountersMockPrometheusTests, onTooBusy)
{
    auto& tooBusyMock = makeMock<CounterInt>("rpc_error_total_number", "{error_type=\"too_busy\"}");
    EXPECT_CALL(tooBusyMock, add(1));
    counters.onTooBusy();
}

TEST_F(RPCCountersMockPrometheusTests, onNotReady)
{
    auto& notReadyMock =
        makeMock<CounterInt>("rpc_error_total_number", "{error_type=\"not_ready\"}");
    EXPECT_CALL(notReadyMock, add(1));
    counters.onNotReady();
}

TEST_F(RPCCountersMockPrometheusTests, onBadSyntax)
{
    auto& badSyntaxMock =
        makeMock<CounterInt>("rpc_error_total_number", "{error_type=\"bad_syntax\"}");
    EXPECT_CALL(badSyntaxMock, add(1));
    counters.onBadSyntax();
}

TEST_F(RPCCountersMockPrometheusTests, onUnknownCommand)
{
    auto& unknownCommandMock =
        makeMock<CounterInt>("rpc_error_total_number", "{error_type=\"unknown_command\"}");
    EXPECT_CALL(unknownCommandMock, add(1));
    counters.onUnknownCommand();
}

TEST_F(RPCCountersMockPrometheusTests, onInternalError)
{
    auto& internalErrorMock =
        makeMock<CounterInt>("rpc_error_total_number", "{error_type=\"internal_error\"}");
    EXPECT_CALL(internalErrorMock, add(1));
    counters.onInternalError();
}

struct RPCCountersMockPrometheusRecotdLedgerRequestTest : RPCCountersMockPrometheusTests {
    testing::StrictMock<util::prometheus::MockHistogramImpl<int64_t>>& ageLedgersHistogramMock =
        makeMock<util::prometheus::HistogramInt>("rpc_requested_ledger_age_histogram", "");
};

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, currentLedger)
{
    // "current" is not tracked in the histogram (it's not a historical ledger lookup)
    // No mock expectations needed
    boost::json::object params;
    params["ledger_index"] = "current";
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, validateLedger)
{
    EXPECT_CALL(ageLedgersHistogramMock, observe(0));

    boost::json::object params;
    params["ledger_index"] = "validated";
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, validatedDefaultLedger)
{
    EXPECT_CALL(ageLedgersHistogramMock, observe(0));

    boost::json::object const params;
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, specificLedger)
{
    auto& ageLedgersHistogramMock =
        makeMock<util::prometheus::HistogramInt>("rpc_requested_ledger_age_histogram", "");

    EXPECT_CALL(ageLedgersHistogramMock, observe(100));  // age is 1000 - 900 = 100

    boost::json::object params;
    params["ledger_index"] = 900;
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, stringNumberLedger)
{
    EXPECT_CALL(ageLedgersHistogramMock, observe(50));  // 1000 - 950 = 50 ledgers

    boost::json::object params;
    params["ledger_index"] = "950";
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, zeroAgeLedger)
{
    auto& ageLedgersHistogramMock =
        makeMock<util::prometheus::HistogramInt>("rpc_requested_ledger_age_histogram", "");

    EXPECT_CALL(ageLedgersHistogramMock, observe(0));  // 1000 - 1000 = 0 ledgers

    boost::json::object params;
    params["ledger_index"] = 1000;  // Same as current
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, ledgerHashRequest)
{
    auto& ledgerHashCounterMock = makeMock<CounterInt>("rpc_ledger_hash_requests_total_number", "");

    EXPECT_CALL(ledgerHashCounterMock, add(1));

    boost::json::object params;
    params["ledger_hash"] = "ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789";
    counters.recordLedgerRequest(params, 1000);
}

TEST_F(RPCCountersMockPrometheusRecotdLedgerRequestTest, ledgerHashWithIndexIgnoresIndex)
{
    auto& ledgerHashCounterMock = makeMock<CounterInt>("rpc_ledger_hash_requests_total_number", "");

    // When both ledger_hash and ledger_index are present, only ledger_hash counter should be
    // incremented
    EXPECT_CALL(ledgerHashCounterMock, add(1));
    // No histogram call should be made

    boost::json::object params;
    params["ledger_hash"] = "ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789";
    params["ledger_index"] = 900;  // This should be ignored
    counters.recordLedgerRequest(params, 1000);
}