#ifndef INCLUDED_C_KOSARAJUSHARIRSCC_H
#define INCLUDED_C_KOSARAJUSHARIRSCC_H

#ifndef INCLUDED_C_DIGRAPH_H
#include <c_Digraph.h>
#endif /*INCLUDED_C_DIGRAPH_H*/

#ifndef INCLUDED_C_VERTEXIDLIST_H
#include <c_VertexIdList.h>
#endif /*INCLUDED_C_VERTEXIDLIST_H*/


/* ------------------------------------------------------------------------------------------------------------------ */
/*  */

typedef struct {
    c_bool_t*          marked;      /* Visited tracking array (size of graph->V) */
    c_size_t*          id;          /* id[v] = component identifier containing v (0 to count-1) */
    c_size_t           count;       /* Total number of strongly connected components discovered */
    c_size_t           V;
    c_Allocator_t      allocator;   /* Deep copy of the user-provided allocator */
} c_KosarajuSharirSCC_t;

/* ------------------------------------------------------------------------------------------------------------------ */
/*  */

/**
 * @brief Computes strongly connected components for the specified digraph.
 * @param allocator Explicit allocator context used to allocate internal arrays
 */
c_err_t c_KosarajuSharirSCC_Init(c_KosarajuSharirSCC_t* self, c_Digraph_t* graph, c_Allocator_t* allocator);

/**
 * @brief Releases internal tracking buffers
 */
void c_KosarajuSharirSCC_Destroy(c_KosarajuSharirSCC_t* self);

/**
 * @brief Are vertices 'v' and 'w' strongly connected (belong to the same SCC)?
 */
C_STATIC_FORCE_INLINE
c_bool_t c_KosarajuSharirSCC_StronglyConnected(c_KosarajuSharirSCC_t* self, c_size_t v, c_size_t w) {
    if (!self || !self->id || v >= self->V || w >= self->V) return C_FALSE;
    return self->id[v] == self->id[w];
}

/**
 * @brief Returns the component id containing vertex 'v'
 * @return Component integer ID (0 to count-1), or C_SIZE_MAX on boundary check failures
 */
C_STATIC_FORCE_INLINE
c_size_t c_KosarajuSharirSCC_GetId(c_KosarajuSharirSCC_t* self, c_size_t v) {
    if (!self || !self->id || v >= self->V) return C_SIZE_MAX;
    return self->id[v];
}

/**
 * @brief Returns the total number of strongly connected components
 */
C_STATIC_FORCE_INLINE
c_size_t c_KosarajuSharirSCC_GetCount(c_KosarajuSharirSCC_t* self) {
    return self ? self->count : 0;
}

#endif /*INCLUDED_C_KOSARAJUSHARIRSCC_H*/