#include "gtest/gtest.h"
#include "storm-config.h"

#include "src/parser/PrismParser.h"
#include "src/models/sparse/Dtmc.h"
#include "src/builder/ExplicitPrismModelBuilder.h"
#include "src/utility/graph.h"
#include "src/utility/shortestPaths.cpp"

// NOTE: These result values of these tests were generated by the
//       KSP-Generator itself and checked for gross implausibility, but no
//       more than that.
//       An independent verification of the values would be really nice ...

TEST(KSPTest, dijkstra) {
    storm::prism::Program program = storm::parser::PrismParser::parse(STORM_CPP_TESTS_BASE_PATH "/functional/builder/brp-16-2.pm");
    std::shared_ptr<storm::models::sparse::Model<double>> model = storm::builder::ExplicitPrismModelBuilder<double>().translateProgram(program);

    storm::storage::sparse::state_type testState = 300;
    storm::utility::ksp::ShortestPathsGenerator<double> spg(model, testState);

    double dist = spg.computeKSP(1);
    EXPECT_DOUBLE_EQ(0.015859334652581887, dist);
}

TEST(KSPTest, singleTarget) {
    storm::prism::Program program = storm::parser::PrismParser::parse(STORM_CPP_TESTS_BASE_PATH "/functional/builder/brp-16-2.pm");
    std::shared_ptr<storm::models::sparse::Model<double>> model = storm::builder::ExplicitPrismModelBuilder<double>().translateProgram(program);

    storm::storage::sparse::state_type testState = 300;
    storm::utility::ksp::ShortestPathsGenerator<double> spg(model, testState);

    double dist = spg.computeKSP(100);
    EXPECT_DOUBLE_EQ(1.5231305000339649e-06, dist);
}

TEST(KSPTest, reentry) {
    storm::prism::Program program = storm::parser::PrismParser::parse(STORM_CPP_TESTS_BASE_PATH "/functional/builder/brp-16-2.pm");
    std::shared_ptr<storm::models::sparse::Model<double>> model = storm::builder::ExplicitPrismModelBuilder<double>().translateProgram(program);

    storm::storage::sparse::state_type testState = 300;
    storm::utility::ksp::ShortestPathsGenerator<double> spg(model, testState);

    double dist = spg.computeKSP(100);
    EXPECT_DOUBLE_EQ(1.5231305000339649e-06, dist);

    // get another distance to ensure re-entry is no problem
    double dist2 = spg.computeKSP(500);
    EXPECT_DOUBLE_EQ(3.0462610000679282e-08, dist2);
}

TEST(KSPTest, groupTarget) {
    storm::prism::Program program = storm::parser::PrismParser::parse(STORM_CPP_TESTS_BASE_PATH "/functional/builder/brp-16-2.pm");
    std::shared_ptr<storm::models::sparse::Model<double>> model = storm::builder::ExplicitPrismModelBuilder<double>().translateProgram(program);

    auto spg = storm::utility::ksp::ShortestPathsGenerator<double>(model, storm::utility::ksp::state_list_t{50, 90});

    // this path should lead to 90
    double dist1 = spg.computeKSP(8);
    EXPECT_DOUBLE_EQ(7.3796982335999988e-06, dist1);

    // this one to 50
    double dist2 = spg.computeKSP(9);
    EXPECT_DOUBLE_EQ(3.92e-06, dist2);

    // this one to 90 again
    double dist3 = spg.computeKSP(12);
    EXPECT_DOUBLE_EQ(3.6160521344640002e-06, dist3);
}