#include "c_Test.h"
#include "c_Digraph.h"
#include "c_NonrecursiveTopological.h"
#include "c_VertexIdList.h"

TEST_CASE(test_nonrecursive_topological_sort) {
    c_Digraph_t g;
    c_Digraph_Init(&g, 4, NULL);

    /* Construct a simple dependency layout DAG:
     * 0 -> 1 -> 3
     * 0 -> 2 -> 3
     */
    c_Digraph_AddEdge(&g, 0, 1);
    c_Digraph_AddEdge(&g, 1, 3);
    c_Digraph_AddEdge(&g, 0, 2);
    c_Digraph_AddEdge(&g, 2, 3);

    c_NonrecursiveTopological_t topo;
    c_err_t err = c_NonrecursiveTopological_Init(&topo, &g, 0);
    ASSERT_INT_EQ(C_SUCCESS, err);
    ASSERT_TRUE(c_NonrecursiveTopological_HasOrder(&topo));

    c_VertexIdList_t result;
    c_VertexIdList_Init(&result, 0, 0);

    err = c_NonrecursiveTopological_GetOrder(&topo, &result);
    ASSERT_INT_EQ(C_SUCCESS, err);
    ASSERT_INT_EQ(4, c_VertexIdList_GetSize(&result));

    /* Verify basic topological layout constraints:
     * 1. 0 must always appear first (no incoming dependencies).
     * 2. 3 must always appear last (depends on everyone else).
     */
    c_uint_t first_v = 0, last_v = 0;
    c_VertexIdList_Get(&result, 0, &first_v);
    c_VertexIdList_Get(&result, 3, &last_v);

    ASSERT_LL_EQ(0, first_v);
    ASSERT_LL_EQ(3, last_v);

    c_VertexIdList_Destroy(&result);
    c_NonrecursiveTopological_Destroy(&topo);
    c_Digraph_Destroy(&g);
}

int main(int argc, char** argv){

    TEST_START(Component Tests);

    // Execution list configurations
    RUN_TEST(test_nonrecursive_topological_sort);

    TEST_REPORT();

    RETURN_TEST_STATUS;
}