/*
 * (C) Copyright 1996- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities
 * granted to it by virtue of its status as an intergovernmental organisation nor
 * does it submit to any jurisdiction.
 */


#include <algorithm>
#include <ios>
#include <memory>
#include <string>
#include <vector>

#include "eckit/testing/Test.h"
#include "eckit/utils/StringTools.h"

#include "mir/action/calc/FormulaAction.h"
#include "mir/action/plan/Action.h"
#include "mir/action/plan/ActionPlan.h"
#include "mir/api/mir_config.h"
#include "mir/data/MIRField.h"
#include "mir/input/MIRInput.h"
#include "mir/key/style/MIRStyle.h"
#include "mir/output/EmptyOutput.h"
#include "mir/param/CombinedParametrisation.h"
#include "mir/param/DefaultParametrisation.h"
#include "mir/param/SimpleParametrisation.h"
#include "mir/util/Exceptions.h"
#include "mir/util/Formula.h"
#include "mir/util/Log.h"

// define EXPECTV(a) log << "\tEXPECT(" << #a <<")" << std::endl; EXPECT(a)


namespace mir::tests::unit {


bool plan_has_action(const action::ActionPlan& plan, const action::Action& action) {
    return (plan.end() != std::find_if(plan.begin(), plan.end(), [&](const action::Action* test) {
                ASSERT(test);
                return test->sameAs(action);
            }));
}


class InputOutput : public param::SimpleParametrisation {
    const std::vector<double> grid{1, 1};

protected:
    explicit InputOutput(bool gridded) {
        gridded ? set("grid", grid).set("gridded", true) : set("truncation", 1).set("spectral", true);
    }
};


struct TestingInput : input::MIRInput, InputOutput {
    explicit TestingInput(bool gridded) : InputOutput(gridded) {}

private:
    const param::MIRParametrisation& parametrisation(size_t /*which*/) const override { return *this; }
    bool sameAs(const MIRInput& /*unused*/) const override { return false; }
    data::MIRField field() const override { NOTIMP; }
    void print(std::ostream& out) const override { InputOutput::print(out); }
    friend std::ostream& operator<<(std::ostream& s, const TestingInput& p) {
        p.print(s);
        return s;
    }
};


struct TestingOutput : InputOutput {
    explicit TestingOutput(bool gridded) : InputOutput(gridded) {}
};


CASE("FormulaAction") {
    Log::info() << std::boolalpha;
    static const param::DefaultParametrisation defaults;

    std::vector<std::string> _when{"prologue", "gridded", "spectral", "raw", "epilogue"};


    const std::string CORRECT_FORMULA("1");
    const std::string WRONG_FORMULA("0");
    const std::string CORRECT_METADATA("param=1");
    const std::string WRONG_METADATA("param=0");

    param::SimpleParametrisation p1;
    param::SimpleParametrisation p2;
    param::SimpleParametrisation p3;
    param::SimpleParametrisation p4;

    p1.set("formula", CORRECT_FORMULA).set("formula.metadata", WRONG_METADATA);
    p2.set("formula", WRONG_FORMULA).set("formula.metadata", CORRECT_METADATA);
    p3.set("formula", WRONG_FORMULA).set("formula.metadata", WRONG_METADATA);
    p4.set("formula", CORRECT_FORMULA).set("formula.metadata", CORRECT_METADATA);

    const action::FormulaAction WRONG_ACTION_1(p1);
    const action::FormulaAction WRONG_ACTION_2(p2);
    const action::FormulaAction WRONG_ACTION_3(p3);
    const action::FormulaAction CORRECT_ACTION(p4);


    std::vector<bool> inputs_gridded{true};
    if constexpr (MIR_HAVE_ATLAS) {
        inputs_gridded.push_back(false);
    }

    for (bool input_gridded : inputs_gridded) {
        TestingInput in(input_gridded);

        for (bool output_gridded : {true, false}) {
            if (input_gridded && !output_gridded) {
                // this combination isn't supported
                continue;
            }

            for (const std::string& when : _when) {

                TestingOutput user(output_gridded);
                user.set("formula." + when, CORRECT_FORMULA);
                user.set("formula." + when + ".metadata", CORRECT_METADATA);

                // test correct user formula.<when> and formula.<when>.metadata, then
                // test extra, inconsistent formula.<when>.metadata options
                bool plan_should_have_formula = when == "gridded"    ? (input_gridded || output_gridded)
                                                : when == "spectral" ? (!input_gridded || !output_gridded)
                                                                     : true;

                for (bool addWrongArguments : {false, true}) {
                    if (addWrongArguments) {
                        for (const std::string& wrongWhen : _when) {
                            if (wrongWhen != when) {
                                user.set("formula." + wrongWhen + ".metadata", WRONG_METADATA);
                            }
                        }
                        if (input_gridded && output_gridded) {
                            user.set("formula.spectral", WRONG_FORMULA);
                        }
                        if (!input_gridded && !output_gridded) {
                            user.set("formula.gridded", WRONG_FORMULA);
                        }
                    }

                    output::EmptyOutput out;

                    const param::CombinedParametrisation param(user, in, defaults);
                    std::unique_ptr<key::style::MIRStyle> style(key::style::MIRStyleFactory::build(param));

                    action::ActionPlan plan(param);
                    style->prepare(plan, out);

                    bool plan_has_this_formula   = plan_has_action(plan, CORRECT_ACTION);
                    bool plan_has_wrong_formulae = plan_has_action(plan, WRONG_ACTION_1) ||
                                                   plan_has_action(plan, WRONG_ACTION_2) ||
                                                   plan_has_action(plan, WRONG_ACTION_3);

                    static size_t c = 1;
                    Log::info() << "Test " << c++ << ":"
                                << "\n\t"
                                   "formula."
                                << when << ", formula." << when << ".metadata"
                                << "\n\t"
                                   "in:   "
                                << in
                                << "\n\t"
                                   "user: "
                                << user
                                << "\n\t"
                                   "plan: "
                                << plan
                                << "\n\t"
                                   "has "
                                << when << " formula: " << plan_has_this_formula << " (should be "
                                << plan_should_have_formula << ")" << std::endl;

                    EXPECT(plan_has_this_formula == plan_should_have_formula);
                    EXPECT(!plan_has_wrong_formulae);
                }
            }
        }
    }
};


CASE("mir::action::Area") {
    Log::info() << std::boolalpha;
    static const param::DefaultParametrisation defaults;

    auto plan_contains =
        [](const action::ActionPlan& plan, const std::string& action) {
            return std::any_of(plan.begin(), plan.end(), [&action](const action::Action* act_ptr) -> bool {
                std::ostringstream str;
                str << *act_ptr;
                return eckit::StringTools::startsWith(str.str(), action);
            });
        };

    // trigger post-processing, but avoid the same points
    param::SimpleParametrisation user;
    user.set("grid", std::vector<double>{2, 2});
    user.set("area", std::vector<double>{90, 0.1, -90, 360});

    TestingInput in(true);
    output::EmptyOutput out;

    const param::CombinedParametrisation param(user, in, defaults);
    std::unique_ptr<key::style::MIRStyle> style(key::style::MIRStyleFactory::build(param));


    SECTION("area-mode=crop for regular lat/lon") {
        user.set("area-mode", "crop");
        user.clear("rotation");

        action::ActionPlan plan(param);
        style->prepare(plan, out);
        EXPECT(plan_contains(plan, "AreaCropper"));
    }


    SECTION("area-mode=mask for regular lat/lon") {
        user.set("area-mode", "mask");
        user.clear("rotation");

        action::ActionPlan plan(param);
        style->prepare(plan, out);
        EXPECT(plan_contains(plan, "AreaMasker"));
    }


    SECTION("area-mode=crop for rotated regular lat/lon") {
        user.set("area-mode", "crop");
        user.set("rotation", std::vector<double>{-90, 0});

        action::ActionPlan plan(param);
        style->prepare(plan, out);
        EXPECT(plan_contains(plan, "AreaCropper"));
    }


    SECTION("area-mode=mask for rotated regular lat/lon") {
        user.set("area-mode", "mask");
        user.set("rotation", std::vector<double>{-90, 0});

        action::ActionPlan plan(param);
        EXPECT_THROWS_AS(style->prepare(plan, out), exception::UserError);
    }
}


}  // namespace mir::tests::unit


int main(int argc, char** argv) {
    return eckit::testing::run_tests(argc, argv);
}