#include "c_Test.h"
#include "c_EdgeWeightedDigraph.h"
#include "c_DijkstraSP.h"


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

    /* Setup paths:
     * 0 -> 1 (Weight: 5.0) [Edge ID: 0]
     * 0 -> 2 (Weight: 1.0) [Edge ID: 1]
     * 2 -> 1 (Weight: 2.0) [Edge ID: 2]
     * 1 -> 3 (Weight: 1.0) [Edge ID: 3]
     * True Shortest path from 0 to 3 is: 0 -> 2 -> 1 -> 3 (Total Weight = 4.0)
     */
    c_EdgeWeightedDigraph_AddEdge(&g, 0, 1, 5.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 0, 2, 1.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 2, 1, 2.0);
    c_EdgeWeightedDigraph_AddEdge(&g, 1, 3, 1.0);

    c_DijkstraSP_t sp;
    err = c_DijkstraSP_Init(&sp, &g, 0, &g.allocator);
    ASSERT_INT_EQ(C_SUCCESS, err);

    ASSERT_TRUE(c_DijkstraSP_HasPathTo(&sp, 3));
    ASSERT_DOUBLE_EQ_MSG(4.0, c_DijkstraSP_DistTo(&sp, 3), "Shortest distance mapping check failed");

    /* Create list to intercept path edge tokens */
    c_VertexIdList_t edge_path;
    c_VertexIdList_Init(&edge_path, 0, 0);

    /* Run the re-implemented signature format */
    err = c_DijkstraSP_PathTo(&sp, 3, &edge_path);
    ASSERT_INT_EQ(C_SUCCESS, err);

    /* Expected edge sequence size should be 3 components long */
    c_size_t path_len = (c_size_t)c_VertexIdList_GetSize(&edge_path);
    ASSERT_LL_EQ(3, path_len);

    /* Extract and verify raw edge pool identity markers sequentially */
    c_uint_t e_id = 0;

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

    c_VertexIdList_Destroy(&edge_path);
    c_DijkstraSP_Destroy(&sp);
    c_EdgeWeightedDigraph_Destroy(&g);
}


int main(void) {
    TEST_START(DijkstraSP_ShortestPath_Suite);
    RUN_TEST(test_dijkstra_path_extraction);
    TEST_REPORT();
    RETURN_TEST_STATUS;
}