#include "pocketpy/interpreter/vm.h"
#include "pocketpy/common/memorypool.h"
#include "pocketpy/common/sstream.h"
#include "pocketpy/pocketpy.h"

static unsigned char* pk_default_import_file(const char* path) { return NULL; }

static void pk_default_stdout(const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
    vfprintf(stdout, fmt, args);
    va_end(args);
    fflush(stdout);
}

static void pk_default_stderr(const char* fmt, ...) {
    va_list args;
    va_start(args, fmt);
    vfprintf(stderr, fmt, args);
    va_end(args);
    fflush(stderr);
}

void pk_TypeInfo__ctor(pk_TypeInfo* self,
                       py_Name name,
                       py_Type base,
                       PyObject* obj,
                       const py_TValue* module,
                       bool subclass_enabled) {
    memset(self, 0, sizeof(pk_TypeInfo));

    self->name = name;
    self->base = base;

    self->self = PyVar__fromobj(obj);
    self->module = module ? *module : PY_NULL;
    self->subclass_enabled = subclass_enabled;

    c11_vector__ctor(&self->annotated_fields, sizeof(py_Name));
}

void pk_TypeInfo__dtor(pk_TypeInfo* self) { c11_vector__dtor(&self->annotated_fields); }

void pk_VM__ctor(pk_VM* self) {
    self->top_frame = NULL;

    pk_NameDict__ctor(&self->modules);
    c11_vector__ctor(&self->types, sizeof(pk_TypeInfo));

    self->StopIteration = PY_NULL;
    self->builtins = PY_NULL;
    self->main = PY_NULL;

    self->_ceval_on_step = NULL;
    self->_import_file = pk_default_import_file;
    self->_stdout = pk_default_stdout;
    self->_stderr = pk_default_stderr;

    self->last_error = NULL;
    self->last_retval = PY_NULL;

    self->__curr_class = PY_NULL;
    self->__cached_object_new = PY_NULL;
    self->__dynamic_func_decl = NULL;

    pk_ManagedHeap__ctor(&self->heap, self);
    ValueStack__ctor(&self->stack);

    self->True = (py_TValue){
        .type = tp_bool,
        .is_ptr = true,
        .extra = 1,
        ._obj = pk_ManagedHeap__gcnew(&self->heap, tp_bool, 0, 0),
    };
    self->False = (py_TValue){
        .type = tp_bool,
        .is_ptr = true,
        .extra = 0,
        ._obj = pk_ManagedHeap__gcnew(&self->heap, tp_bool, 0, 0),
    };
    self->None = (py_TValue){
        .type = tp_none_type,
        .is_ptr = true,
        ._obj = pk_ManagedHeap__gcnew(&self->heap, tp_none_type, 0, 0),
    };
    self->NotImplemented = (py_TValue){
        .type = tp_not_implemented_type,
        .is_ptr = true,
        ._obj = pk_ManagedHeap__gcnew(&self->heap, tp_not_implemented_type, 0, 0),
    };
    self->Ellipsis = (py_TValue){
        .type = tp_ellipsis,
        .is_ptr = true,
        ._obj = pk_ManagedHeap__gcnew(&self->heap, tp_ellipsis, 0, 0),
    };

    /* Init Builtin Types */
    // 0: unused
    pk_TypeInfo__ctor(c11_vector__emplace(&self->types), 0, 0, NULL, NULL, false);
#define validate(t, expr)                                                                          \
    if(t != (expr)) abort()

    validate(tp_object, pk_VM__new_type(self, "object", 0, NULL, true));
    validate(tp_type, pk_VM__new_type(self, "type", 1, NULL, false));

    validate(tp_int, pk_VM__new_type(self, "int", tp_object, NULL, false));
    validate(tp_float, pk_VM__new_type(self, "float", tp_object, NULL, false));
    validate(tp_bool, pk_VM__new_type(self, "bool", tp_object, NULL, false));
    validate(tp_str, pk_VM__new_type(self, "str", tp_object, NULL, false));

    validate(tp_list, pk_list__register());
    validate(tp_tuple, pk_VM__new_type(self, "tuple", tp_object, NULL, false));

    validate(tp_slice, pk_VM__new_type(self, "slice", tp_object, NULL, false));
    validate(tp_range, pk_VM__new_type(self, "range", tp_object, NULL, false));
    validate(tp_module, pk_VM__new_type(self, "module", tp_object, NULL, false));

    validate(tp_function, pk_VM__new_type(self, "function", tp_object, NULL, false));
    validate(tp_nativefunc, pk_VM__new_type(self, "nativefunc", tp_object, NULL, false));
    validate(tp_bound_method, pk_VM__new_type(self, "bound_method", tp_object, NULL, false));

    validate(tp_super, pk_VM__new_type(self, "super", tp_object, NULL, false));
    validate(tp_exception, pk_VM__new_type(self, "Exception", tp_object, NULL, true));
    validate(tp_bytes, pk_VM__new_type(self, "bytes", tp_object, NULL, false));
    validate(tp_mappingproxy, pk_VM__new_type(self, "mappingproxy", tp_object, NULL, false));

    validate(tp_dict, pk_VM__new_type(self, "dict", tp_object, NULL, true));
    validate(tp_property, pk_VM__new_type(self, "property", tp_object, NULL, false));
    validate(tp_star_wrapper, pk_VM__new_type(self, "star_wrapper", tp_object, NULL, false));

    validate(tp_staticmethod, pk_VM__new_type(self, "staticmethod", tp_object, NULL, false));
    validate(tp_classmethod, pk_VM__new_type(self, "classmethod", tp_object, NULL, false));

    validate(tp_none_type, pk_VM__new_type(self, "NoneType", tp_object, NULL, false));
    validate(tp_not_implemented_type,
             pk_VM__new_type(self, "NotImplementedType", tp_object, NULL, false));
    validate(tp_ellipsis, pk_VM__new_type(self, "ellipsis", tp_object, NULL, false));

    validate(tp_op_call, pk_VM__new_type(self, "__op_call", tp_object, NULL, false));
    validate(tp_op_yield, pk_VM__new_type(self, "__op_yield", tp_object, NULL, false));

    validate(tp_syntax_error, pk_VM__new_type(self, "SyntaxError", tp_exception, NULL, false));
    validate(tp_stop_iteration, pk_VM__new_type(self, "StopIteration", tp_exception, NULL, false));
#undef validate

    self->StopIteration = c11__at(pk_TypeInfo, &self->types, tp_stop_iteration)->self;
    self->builtins = *py_newmodule("builtins", NULL);

    /* Setup Public Builtin Types */
    py_Type public_types[] = {tp_object,
                              tp_type,
                              tp_int,
                              tp_float,
                              tp_bool,
                              tp_str,
                              tp_list,
                              tp_tuple,
                              tp_slice,
                              tp_range,
                              tp_bytes,
                              tp_dict,
                              tp_property,
                              tp_exception,
                              tp_stop_iteration,
                              tp_syntax_error};

    for(int i = 0; i < PK_ARRAY_COUNT(public_types); i++) {
        py_Type t = public_types[i];
        pk_TypeInfo* ti = c11__at(pk_TypeInfo, &self->types, t);
        py_setdict(&self->builtins, ti->name, &ti->self);
    }
    py_setdict(&self->builtins, py_name("NotImplemented"), &self->NotImplemented);

    /* Do Buildin Bindings*/
    pk_VM__init_builtins(self);
    self->main = *py_newmodule("__main__", NULL);
}

void pk_VM__dtor(pk_VM* self) {
    if(self->__dynamic_func_decl) { PK_DECREF(self->__dynamic_func_decl); }
    // destroy all objects
    pk_ManagedHeap__dtor(&self->heap);
    // clear frames
    // ...
    pk_NameDict__dtor(&self->modules);
    c11_vector__dtor(&self->types);
    ValueStack__clear(&self->stack);
}

void pk_VM__push_frame(pk_VM* self, Frame* frame) {
    frame->f_back = self->top_frame;
    self->top_frame = frame;
}

void pk_VM__pop_frame(pk_VM* self) {
    assert(self->top_frame);
    Frame* frame = self->top_frame;
    // reset stack pointer
    self->stack.sp = frame->p0;
    // pop frame and delete
    self->top_frame = frame->f_back;
    Frame__delete(frame);
}

py_Type pk_VM__new_type(pk_VM* self,
                        const char* name,
                        py_Type base,
                        const py_TValue* module,
                        bool subclass_enabled) {
    py_Type type = self->types.count;
    pk_TypeInfo* ti = c11_vector__emplace(&self->types);
    PyObject* typeobj = pk_ManagedHeap__gcnew(&self->heap, tp_type, -1, sizeof(py_Type));
    py_Type* value = PyObject__value(typeobj);
    *value = type;
    pk_TypeInfo__ctor(ti, py_name(name), base, typeobj, module, subclass_enabled);
    return type;
}

/****************************************/
void PyObject__delete(PyObject* self) {
    pk_TypeInfo* ti = c11__at(pk_TypeInfo, &pk_current_vm->types, self->type);
    if(ti->dtor) ti->dtor(PyObject__value(self));
    if(self->slots == -1) pk_NameDict__dtor(PyObject__dict(self));
    if(self->gc_is_large) {
        free(self);
    } else {
        PoolObject_dealloc(self);
    }
}

void pk_ManagedHeap__mark(pk_ManagedHeap* self) {
    // for(int i=0; i<self->no_gc.count; i++){
    //     PyObject* obj = c11__getitem(PyObject*, &self->no_gc, i);
    //     vm->__obj_gc_mark(obj);
    // }
    // vm->callstack.apply([vm](Frame& frame) {
    //     frame._gc_mark(vm);
    // });
    // vm->obj_gc_mark(vm->__last_exception);
    // vm->obj_gc_mark(vm->__curr_class);
    // vm->obj_gc_mark(vm->__c.error);
    // vm->__stack_gc_mark(vm->s_data.begin(), vm->s_data.end());
    // if(self->_gc_marker_ex) self->_gc_marker_ex((pkpy_VM*)vm);
}