/* Copyright (c) 2020 Contrast Security, Inc.  See
 * https://www.contrastsecurity.com/enduser-terms-0317a for more details. */

#include "cs__scope.h"
#include <ruby.h>

VALUE in_given_scope(const VALUE object, const char *scope) {
    VALUE level;
    level = rb_iv_get(object, scope);
    if (NUM2INT(level) > 0) {
        return Qtrue;
    }
    return Qfalse;
}

void enter_given_scope(const VALUE object, const char *scope) {
    int level = NUM2INT(rb_iv_get(object, scope));
    rb_iv_set(object, scope, INT2NUM(level + 1));
}

void exit_given_scope(const VALUE object, const char *scope) {
    int level = NUM2INT(rb_iv_get(object, scope));
    rb_iv_set(object, scope, INT2NUM(level - 1));
}

VALUE in_contrast_scope(const VALUE self) {
    return in_given_scope(self, ivar_contrast_scope);
}

VALUE enter_contrast_scope(const VALUE self) {
    enter_given_scope(self, ivar_contrast_scope);
    return Qnil;
}

VALUE exit_contrast_scope(const VALUE self) {
    exit_given_scope(self, ivar_contrast_scope);
    return Qnil;
}

VALUE run_in_scope(const VALUE self) {
    enter_contrast_scope(self);
    rb_ensure(rb_yield, Qundef, exit_contrast_scope, self);
    return Qnil;
}

VALUE enter_scope_for(const VALUE self, const VALUE scope_symbol) {
    enter_contrast_scope(self);

    return Qnil;
}

VALUE exit_scope_for(const VALUE self, const VALUE scope_symbol) {
    exit_contrast_scope(self);

    return Qnil;
}

VALUE initialize(const VALUE self) {
    rb_iv_set(self, ivar_contrast_scope, rbzero);

    return self;
}

VALUE deep_clone(const VALUE self) {
    VALUE new_scope = rb_funcall(scope_class, rb_sym_new, 0);
    rb_iv_set(new_scope, ivar_contrast_scope,
              rb_iv_get(self, ivar_contrast_scope));
    return new_scope;
}

void Init_cs__scope(void) {
    rb_sym_new = rb_intern("new");
    VALUE contrast = rb_define_module("Contrast");
    VALUE agent = rb_define_module_under(contrast, "Agent");
    scope_class = rb_define_class_under(agent, "Scope", rb_cObject);
    rb_define_method(scope_class, "initialize", initialize, 0);

    ivar_contrast_scope = "@contrast_scope";

    rb_define_const(scope_class, "CONTRAST_SCOPE",
                    ID2SYM(rb_intern("contrast")));
    CONTRAST_SCOPE = rb_const_get(scope_class, rb_intern("CONTRAST_SCOPE"));

    rb_define_method(scope_class, "in_contrast_scope?", in_contrast_scope, 0);

    rb_define_method(scope_class, "enter_contrast_scope", enter_contrast_scope,
                     0);
    rb_define_method(scope_class, "exit_contrast_scope", exit_contrast_scope,
                     0);

    rb_define_method(scope_class, "run_in_scope", run_in_scope, 0);
    rb_define_method(scope_class, "enter_scope_for", enter_scope_for, 1);
    rb_define_method(scope_class, "exit_scope_for", exit_scope_for, 1);

    rb_define_method(scope_class, "deep_clone", deep_clone, 0);
}