#include "catch2/catch.hpp"

#include "TestUtils.hpp"

#include "EngineFactory.hpp"
#include "Engine.hpp"
#include "Fen.hpp"
#include "Board.hpp"

static std::unique_ptr<Engine> createEngine() {
    return EngineFactory::createEngine();
}

static void testGameEnd(const char* fen, bool isMate) {
    auto engine = createEngine();
    REQUIRE(engine != nullptr);

    auto board = Fen::createBoard(fen);
    REQUIRE(board.has_value());

    auto pv = engine->pv(board.value());

    REQUIRE(pv.isMate() == isMate);
    REQUIRE(pv.score() == 0);
    REQUIRE(pv.length() == 0);
}

static void testMove(const char *fen, const std::vector<std::string> &expectedMoves) {
    auto engine = createEngine();
    REQUIRE(engine != nullptr);

    auto board = Fen::createBoard(fen);
    REQUIRE(board.has_value());

    for (const auto &moveName : expectedMoves) {
        auto pv = engine->pv(board.value());
        Move move = *pv.begin();
        move.setScore(0);
        REQUIRE(move == Move::fromUci(moveName));
        board->makeMove(move);
    }

}

TEST_CASE("Engine detects checkmate", "[Engine][Checkmate]") {
    auto fen = GENERATE(
        // https://lichess.org/editor/4R2k/6pp/8/8/8/8/8/K7_b_-_-_0_1
        "4R2k/6pp/8/8/8/8/8/K7 b - - 0 1",
        // https://lichess.org/editor/7k/8/8/8/1bb5/8/r7/3BK3_w_-_-_0_1
        "7k/8/8/8/1bb5/8/r7/3BK3 w - - 0 1"
    );

    testGameEnd(fen, true);
}

TEST_CASE("Engine detects stalemate", "[Engine][Stalemate]") {
    auto fen = GENERATE(
        // https://lichess.org/editor/k7/p7/P7/8/8/8/8/KR6_b_-_-_0_1
        "k7/p7/P7/8/8/8/8/KR6 b - - 0 1",
        // https://lichess.org/editor/k7/8/8/6n1/r7/4K3/2q5/8_w_-_-_0_1
        "k7/8/8/6n1/r7/4K3/2q5/8 w - - 0 1"
    );

    testGameEnd(fen, false);
}

TEST_CASE("Puzzles mateIn1_simple", "[Engine][Puzzle]") {
    auto [fen, moves] = GENERATE(table<const char*, std::vector<std::string>>({
        {"2bQ1k1r/1p3p2/p4b1p/4pNp1/2q5/8/PPP2PPP/1K1RR3 b - - 3 23",{"f6d8", "d1d8"}}, // https://lichess.org/gQa01loO/black#46
        {"5rk1/ppp5/2n4p/3b2p1/6R1/P1B1P2P/1Pq5/R2Q2K1 b - - 3 29",{"c2f2"}}, // https://lichess.org/haKJxadR#57
        {"r1b1k2r/ppp2pp1/2p5/2b1q1Bp/3PP1n1/2P5/PP2BPPP/RN1Q1RK1 b kq - 0 10",{"e5h2"}},
        {"r3rk2/5ppQ/b1pp1q1p/p5n1/P1P5/2N5/1PB2PP1/R3R1K1 w - - 6 24", {"h7h8"}},
    }));
    testMove(fen, moves);
}