from libc.string cimport memcpy


cdef int begin_entity(State* s, label) except -1:
    s.j += 1
    s.ents[s.j].start = s.i
    s.ents[s.j].tag = label
    s.ents[s.j].end = s.i + 1


cdef int end_entity(State* s) except -1:
    s.ents[s.j].end = s.i + 1


cdef State* init_state(Pool mem, int sent_length) except NULL:
    s = <State*>mem.alloc(1, sizeof(State))
    s.ents = <Entity*>mem.alloc(sent_length, sizeof(Entity))
    s.tags = <int*>mem.alloc(sent_length, sizeof(int))
    s.length = sent_length


cdef bint entity_is_open(State *s) except -1:
    return s.ents[s.j].start != 0


cdef int entity_is_sunk(State *s, Move* golds) except -1:
    if not entity_is_open(s):
        return False
    raise StandardError
    #cdef Entity* ent = &s.ents[s.j]
    #cdef Move* gold = &golds[ent.start]
    #if gold.action != BEGIN and gold.action != UNIT:
    #    return True
    #elif gold.label != ent.label:
    #    return True
    #else:
    #    return False


cdef int copy_state(Pool mem, State* dest, State* source) except -1:
    '''Copy state source into state dest.'''
    if source.length > dest.length:
        dest.ents = <Entity*>mem.realloc(dest.ents, source.length * sizeof(Entity))
        dest.tags = <int*>mem.realloc(dest.tags, source.length * sizeof(int))
    memcpy(dest.ents, source.ents, source.length * sizeof(Entity))
    memcpy(dest.tags, source.tags, source.length * sizeof(int))
    dest.length = source.length
    dest.i = source.i
    dest.j = source.j
    dest.curr = source.curr


cdef int is_done(State* s) except -1:
    return s.i >= s.length and not entity_is_open(s)