#include "symtab.h"

#include <stdlib.h>
#include <assert.h>
#include <string.h>

#include "sv.h"

void symtab_init(struct symbol_table *symtab)
{
	assert(symtab != NULL);
	symtab->cap = 150;
	symtab->count = 0;
	symtab->entries = malloc(150);
}

void symtab_expand(struct symbol_table *symtab)
{
	assert(symtab != NULL);
	size_t newcap = symtab->cap * 2;
        void* newbuf = malloc(newcap);
	memcpy(newbuf, symtab->entries, symtab->cap);
	free(symtab->entries);
	symtab->cap = newcap;
	symtab->entries = newbuf;
}

void symtab_free(struct symbol_table *symtab)
{
	assert(symtab != NULL);
	symtab->count = 0;
	symtab->cap = 0;
	free(symtab->entries);
}

struct symlookup_result symtab_lookup(struct symbol_table *symtab,  struct string_view ent)
{
	for(size_t i = 0; i < symtab->count; i++) {
		struct symbol_entry *syment = &symtab->entries[i];

		if(ent.len != syment->name.len) continue;
		
		if(strncmp(ent.buf, syment->name.buf, ent.len) == 0) {
			return (struct symlookup_result){.ent = syment, .i = i};
		}
	}
	return (struct symlookup_result){.ent = NULL, .i = 0};
}

size_t symtab_append(struct symbol_table *symtab, struct symbol_entry syment)
{
	if(symtab->count + 1 >= symtab->cap) symtab_expand(symtab);
	symtab->entries[symtab->count++] = syment;
	return symtab->count - 1;
}