/*
 *  Created by Phil on 7/1/2011
 *  Copyright 2010 Two Blue Cubes Ltd. All rights reserved.
 *
 *  Distributed under the Boost Software License, Version 1.0. (See accompanying
 *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 */
#ifndef TWOBLUECUBES_CATCH_TEST_CASE_REGISTRY_IMPL_HPP_INCLUDED
#define TWOBLUECUBES_CATCH_TEST_CASE_REGISTRY_IMPL_HPP_INCLUDED

#include "catch_test_registry.hpp"
#include "catch_test_case_info.h"
#include "catch_test_spec.hpp"
#include "catch_context.h"
#include "catch_interfaces_config.h"

#include <vector>
#include <set>
#include <sstream>
#include <algorithm>


namespace Catch {

    struct RandomNumberGenerator {
        typedef std::ptrdiff_t result_type;

        result_type operator()( result_type n ) const { return std::rand() % n; }

        static constexpr result_type min() { return 0; }
        static constexpr result_type max() { return 1000000; }
        result_type operator()() const { return std::rand() % max(); }
        template<typename V>
        static void shuffle( V& vector ) {
            RandomNumberGenerator rng;
            std::shuffle( vector.begin(), vector.end(), rng );
        }
    };

    inline std::vector<TestCase> sortTests( IConfig const& config, std::vector<TestCase> const& unsortedTestCases ) {

        std::vector<TestCase> sorted = unsortedTestCases;

        switch( config.runOrder() ) {
            case RunTests::InLexicographicalOrder:
                std::sort( sorted.begin(), sorted.end() );
                break;
            case RunTests::InRandomOrder:
                {
                    seedRng( config );
                    RandomNumberGenerator::shuffle( sorted );
                }
                break;
            case RunTests::InDeclarationOrder:
                // already in declaration order
                break;
        }
        return sorted;
    }
    bool matchTest( TestCase const& testCase, TestSpec const& testSpec, IConfig const& config ) {
        return testSpec.matches( testCase ) && ( config.allowThrows() || !testCase.throws() );
    }

    void enforceNoDuplicateTestCases( std::vector<TestCase> const& functions ) {
        std::set<TestCase> seenFunctions;
        for( auto const& function : functions ) {
            auto prev = seenFunctions.insert( function );
            CATCH_ENFORCE( prev.second,
                    "error: TEST_CASE( \"" << function.name << "\" ) already defined.\n"
                    << "\tFirst seen at " << prev.first->getTestCaseInfo().lineInfo << "\n"
                    << "\tRedefined at " << function.getTestCaseInfo().lineInfo );
        }
    }

    std::vector<TestCase> filterTests( std::vector<TestCase> const& testCases, TestSpec const& testSpec, IConfig const& config ) {
        std::vector<TestCase> filtered;
        filtered.reserve( testCases.size() );
        for( auto const& testCase : testCases )
            if( matchTest( testCase, testSpec, config ) )
                filtered.push_back( testCase );
        return filtered;
    }
    std::vector<TestCase> const& getAllTestCasesSorted( IConfig const& config ) {
        return getRegistryHub().getTestCaseRegistry().getAllTestsSorted( config );
    }

    class TestRegistry : public ITestCaseRegistry {
    public:
        virtual ~TestRegistry();

        virtual void registerTest( TestCase const& testCase ) {
            std::string name = testCase.getTestCaseInfo().name;
            if( name.empty() ) {
                std::ostringstream oss;
                oss << "Anonymous test case " << ++m_unnamedCount;
                return registerTest( testCase.withName( oss.str() ) );
            }
            m_functions.push_back( testCase );
        }

        virtual std::vector<TestCase> const& getAllTests() const {
            return m_functions;
        }
        virtual std::vector<TestCase> const& getAllTestsSorted( IConfig const& config ) const {
            if( m_sortedFunctions.empty() )
                enforceNoDuplicateTestCases( m_functions );

            if(  m_currentSortOrder != config.runOrder() || m_sortedFunctions.empty() ) {
                m_sortedFunctions = sortTests( config, m_functions );
                m_currentSortOrder = config.runOrder();
            }
            return m_sortedFunctions;
        }

    private:
        std::vector<TestCase> m_functions;
        mutable RunTests::InWhatOrder m_currentSortOrder = RunTests::InDeclarationOrder;
        mutable std::vector<TestCase> m_sortedFunctions;
        size_t m_unnamedCount = 0;
        std::ios_base::Init m_ostreamInit; // Forces cout/ cerr to be initialised
    };

    TestRegistry::~TestRegistry() {}


    ///////////////////////////////////////////////////////////////////////////

    class TestInvokerAsFunction : public ITestInvoker {
        void(*m_testAsFunction)();
    public:
        TestInvokerAsFunction( void(*testAsFunction)() ) : m_testAsFunction( testAsFunction ) {}

        void invoke() const override {
            m_testAsFunction();
        }
    };

    inline std::string extractClassName( std::string const& classOrQualifiedMethodName ) {
        std::string className = classOrQualifiedMethodName;
        if( startsWith( className, '&' ) )
        {
            std::size_t lastColons = className.rfind( "::" );
            std::size_t penultimateColons = className.rfind( "::", lastColons-1 );
            if( penultimateColons == std::string::npos )
                penultimateColons = 1;
            className = className.substr( penultimateColons, lastColons-penultimateColons );
        }
        return className;
    }

    void registerTestCase
        (   ITestInvoker* testCase,
            char const* classOrQualifiedMethodName,
            NameAndDesc const& nameAndDesc,
            SourceLineInfo const& lineInfo ) {
        try {
            getMutableRegistryHub().registerTest
            (makeTestCase
            (testCase,
             extractClassName(classOrQualifiedMethodName),
             nameAndDesc.name,
             nameAndDesc.description,
             lineInfo));
        } catch (...) {
            // Do not throw when constructing global objects, instead register the exception to be processed later
            getMutableRegistryHub().registerStartupException( std::current_exception() );
        }
    }
    void registerTestCaseFunction
        (   TestFunction function,
            SourceLineInfo const& lineInfo,
            NameAndDesc const& nameAndDesc ) {
        registerTestCase( new TestInvokerAsFunction( function ), "", nameAndDesc, lineInfo );
    }

    ///////////////////////////////////////////////////////////////////////////

    AutoReg::AutoReg
        (   TestFunction function,
            SourceLineInfo const& lineInfo,
            NameAndDesc const& nameAndDesc ) {
        registerTestCaseFunction( function, lineInfo, nameAndDesc );
    }

    AutoReg::~AutoReg() {}

} // end namespace Catch


#endif // TWOBLUECUBES_CATCH_TEST_CASE_REGISTRY_IMPL_HPP_INCLUDED