#include "../objects/object.h"
#include "../frontend/parser.h"

typedef struct
{
    char *name;
    size_t value; // offset al Object en el allocator
} Variable;

typedef struct
{
    Variable vars[256];
    int count;
} Environment;

size_t env_get(Environment *env, const char *name)
{
    for (int i = 0; i < env->count; i++)
    {
        if (strcmp(env->vars[i].name, name) == 0)
        {
            return env->vars[i].value;
        }
    }

    printf("ERROR: variable '%s' no definida\n", name);
    exit(1);
}

void env_set(Environment *env, const char *name, size_t value)
{
    for (int i = 0; i < env->count; i++)
    {
        if (strcmp(env->vars[i].name, name) == 0)
        {
            env->vars[i].value = value;
            return;
        }
    }

    // No existe, añadir
    env->vars[env->count].name = (char *)name;
    env->vars[env->count].value = value;
    env->count++;
}

size_t eval(ASTNode *node, Environment *env, void *allocator) {
    switch (node->type) {
        case NODE_INT_LIT:
            return obj_new_int(allocator, node->data.int_val);
        case NODE_VAR:
            return env_get(env, node->data.string_val);
        case NODE_ASSIGN: {
            size_t val = eval(node->data.assign.value, env, allocator);
            env_set(env, node->data.assign.name, val);
            return val;
        }
        case NODE_BINOP: {
            size_t left = eval(node->data.binop.left, env, allocator);
            size_t right = eval(node->data.binop.right, env, allocator);

            // Resolver objects
            Object* l = (Object *) JLANG_RESOLVE(allocator, left);
            Object* r = (Object *) JLANG_RESOLVE(allocator, right);

            // Operar (ints por ahora)
            if (node->data.binop.op == '+'){
                return obj_new_int(allocator, l->data.int_val + r->data.int_val);
            } else if (node->data.binop.op == '-') {
                return obj_new_int(allocator, l->data.int_val - r->data.int_val);
            }
        }
        case NODE_PRINT: {
            size_t val = eval(node->data.print.expr, env, allocator);
            obj_print(allocator, val, "");
            printf("\n");
            return val;
        }        
        case NODE_BLOCK:
            for (int i=0; i< node->data.block.count; i++)
                eval(node->data.block.stmts[i], env, allocator);
            return 0;
        default:
            break;
    }
}