// widgetClass.c  -- Widget class table and dynamic registration
//
// The widgetClassTable[] is the central dispatch table for the widget
// system.  All entries start NULL and are filled at runtime by widget
// DXE registration functions (wgtBoxRegister, wgtButtonRegister, etc.).
// The loader loads each widget DXE and calls its register function
// before starting the shell.
//
// This file contains only the table and the dynamic registration API.
// All class definitions live in their respective widget .c files.

#include "widgetInternal.h"

// ============================================================
// Class table  -- indexed by WidgetTypeE
// ============================================================
//
// Every entry is NULL until the corresponding widget DXE calls its
// registration function (e.g. wgtBoxRegister sets VBox/HBox/Frame).
// Sized WGT_MAX_TYPES to accommodate both built-in widget types
// (0..WGT_TYPE_BUILTIN_COUNT-1) and dynamically registered types
// (WGT_TYPE_DYNAMIC_BASE..WGT_MAX_TYPES-1).

const WidgetClassT *widgetClassTable[WGT_MAX_TYPES];


// ============================================================
// wgtRegisterClass  -- register a dynamic widget type at runtime
// ============================================================
//
// External DXE plugins call this to add new widget types without
// modifying the core library.  Returns the assigned type ID
// (>= WGT_TYPE_DYNAMIC_BASE) so the caller can use it with
// widgetAlloc().  Returns -1 if the table is full.

int32_t wgtRegisterClass(const WidgetClassT *wclass) {
    if (!wclass) {
        return -1;
    }

    for (int32_t i = WGT_TYPE_DYNAMIC_BASE; i < WGT_MAX_TYPES; i++) {
        if (!widgetClassTable[i]) {
            widgetClassTable[i] = wclass;
            return i;
        }
    }

    return -1;
}