#include <c_TransitiveClosure.h>

c_err_t c_TransitiveClosure_Init(c_TransitiveClosure_t* self, c_Digraph_t* graph, c_Allocator_t* allocator) {
    if (!self || !graph) return C_ERR_PARAM;

    self->allocator = allocator ? *allocator : c_DefaultAllocator;
    self->V = graph->V;
    self->dfs_matrix = NULL;

    if (self->V == 0) return C_SUCCESS;

    /* 1. Allocate an array of non-recursive DFS structures */
    self->dfs_matrix = (c_NonrecursiveDirectedDFS_t*)c_Allocator_Calloc(
        &self->allocator,
        self->V,
        sizeof(c_NonrecursiveDirectedDFS_t)
    );
    if (!self->dfs_matrix) return C_ERR_NOMEM;

    /* 2. Run a non-recursive DFS starting from each individual vertex */
    for (c_size_t v = 0; v < self->V; ++v) {
        c_err_t err = c_NonrecursiveDirectedDFS_Init(&self->dfs_matrix[v], graph, v, allocator);

        if (err != C_SUCCESS) {
            /* Clean up previously initialized instances to avoid memory leaks if OOM occurs mid-way */
            for (c_size_t i = 0; i < v; ++i) {
                c_NonrecursiveDirectedDFS_Destroy(&self->dfs_matrix[i]);
            }
            c_Allocator_Free(&self->allocator, self->dfs_matrix);
            self->dfs_matrix = NULL;
            self->V = 0;
            return err;
        }
    }

    return C_SUCCESS;
}

void c_TransitiveClosure_Destroy(c_TransitiveClosure_t* self) {
    if (!self) return;

    if (self->dfs_matrix) {
        /* Deallocate every independent tracking instance matrix block */
        for (c_size_t i = 0; i < self->V; ++i) {
            c_NonrecursiveDirectedDFS_Destroy(&self->dfs_matrix[i]);
        }
        c_Allocator_Free(&self->allocator, self->dfs_matrix);
        self->dfs_matrix = NULL;
    }
    self->V = 0;
}