#include "c_Test.h"
#include "c_Digraph.h"
#include "c_KosarajuSharirSCC.h"

TEST_CASE(test_kosaraju_sharir_scc_clustering) {
    c_Digraph_t g;
    c_err_t err = c_Digraph_Init(&g, 5, NULL);
    ASSERT_INT_EQ(C_SUCCESS, err);

    /* Construct a graph topology with 2 separate SCC groups:
     * Component 1 (Loop group): 0 -> 1 -> 2 -> 0
     * Bridge link exiting out:  2 -> 3
     * Component 2 (Loop group): 3 -> 4 -> 3
     */
    c_Digraph_AddEdge(&g, 0, 1);
    c_Digraph_AddEdge(&g, 1, 2);
    c_Digraph_AddEdge(&g, 2, 0);

    c_Digraph_AddEdge(&g, 2, 3); /* Bridge connection */

    c_Digraph_AddEdge(&g, 3, 4);
    c_Digraph_AddEdge(&g, 4, 3);

    c_KosarajuSharirSCC_t scc;
    err = c_KosarajuSharirSCC_Init(&scc, &g, 0);
    ASSERT_INT_EQ(C_SUCCESS, err);

    /* Total strong connected component clusters count must equal exactly 2 */
    ASSERT_LL_EQ(2, c_KosarajuSharirSCC_GetCount(&scc));

    /* Verify cluster properties (0, 1, 2 must have the exact same group ID) */
    ASSERT_TRUE(c_KosarajuSharirSCC_StronglyConnected(&scc, 0, 1));
    ASSERT_TRUE(c_KosarajuSharirSCC_StronglyConnected(&scc, 1, 2));

    /* 3 and 4 must have the exact same group ID */
    ASSERT_TRUE(c_KosarajuSharirSCC_StronglyConnected(&scc, 3, 4));

    /* Cross verification check (0 and 3 are isolated in different clusters) */
    ASSERT_FALSE(c_KosarajuSharirSCC_StronglyConnected(&scc, 0, 3));

    c_KosarajuSharirSCC_Destroy(&scc);
    c_Digraph_Destroy(&g);
}


int main(int argc, char** argv){
    TEST_START(c_NonrecursiveDFS Component Tests);

    // Execution list configurations
    RUN_TEST(test_kosaraju_sharir_scc_clustering);

    TEST_REPORT();

    RETURN_TEST_STATUS;

    return 0;
}