#include "c_Test.h"
#include "c_EdgeWeightedDigraph.h"
#include "c_AcyclicLP.h"
#include "c_VertexIdList.h"

TEST_CASE(test_acyclic_longest_paths_dag) {
    c_EdgeWeightedDigraph_t g;
    c_err_t err = c_EdgeWeightedDigraph_Init(&g, 4, NULL);
    ASSERT_INT_EQ(C_SUCCESS, err);

    /*
     * Construct a valid DAG layout to measure longest path selection capabilities:
     * 0 -> 1 (Weight: 2.0) [Edge 0]
     * 0 -> 2 (Weight: 1.0) [Edge 1]
     * 1 -> 2 (Weight: 5.0) [Edge 2] -> Path 0->1->2 total is 2.0 + 5.0 = 7.0 (Longer than direct 0->2 edge)
     * 2 -> 3 (Weight: 3.0) [Edge 3] -> Path 0->1->2->3 total is 7.0 + 3.0 = 10.0
     */
    c_EdgeWeightedDigraph_AddEdge(&g, 0, 1, 2.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 0, 2, 1.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 1, 2, 5.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 2, 3, 3.0);

    c_AcyclicLP_t lp;
    err = c_AcyclicLP_Init(&lp, &g, 0, &g.allocator);
    ASSERT_INT_EQ(C_SUCCESS, err);

    /* Verify longest path evaluation weights values */
    ASSERT_TRUE(c_AcyclicLP_HasPathTo(&lp, 3));
    ASSERT_DOUBLE_EQ_MSG(7.0, c_AcyclicLP_DistTo(&lp, 2), "Critical intermediate length calculation mismatch");
    ASSERT_DOUBLE_EQ_MSG(10.0, c_AcyclicLP_DistTo(&lp, 3), "DAG critical terminal timeline calculation wrong");

    /* Reconstruct edge sequence arrays elements */
    c_VertexIdList_t edge_path;
    c_VertexIdList_Init(&edge_path, 0, 0);

    err = c_AcyclicLP_PathTo(&lp, 3, &edge_path);
    ASSERT_INT_EQ(C_SUCCESS, err);
    ASSERT_LL_EQ(3, (c_size_t)c_VertexIdList_GetSize(&edge_path));

    c_uint_t e_id = 0;
    c_VertexIdList_Get(&edge_path, 0, &e_id); ASSERT_LL_EQ(0, e_id); /* Edge 0 (0->1) */
    c_VertexIdList_Get(&edge_path, 1, &e_id); ASSERT_LL_EQ(2, e_id); /* Edge 2 (1->2) */
    c_VertexIdList_Get(&edge_path, 2, &e_id); ASSERT_LL_EQ(3, e_id); /* Edge 3 (2->3) */

    c_VertexIdList_Destroy(&edge_path);
    c_AcyclicLP_Destroy(&lp);
    c_EdgeWeightedDigraph_Destroy(&g);
}

int main(void) {
    TEST_START(AcyclicLP_DAG_Maximization_Suite);
    RUN_TEST(test_acyclic_longest_paths_dag);
    TEST_REPORT();
    RETURN_TEST_STATUS;
}