// https://github.com/frida/frida-gum/blob/bd6f95d391b198d7d87264ba56f2972efc7298ec/bindings/gumjs/gumquickscriptbackend.c#L259

const char * const package_marker = "📦\n";
const char * const delimiter_marker = "\n✄\n";
const char * const alias_marker = "↻ ";

static void r2qjs_dump_obj(JSContext *ctx, JSValueConst val);

static char *r2qjs_normalize_path(const char *root, const char *base_name, const char *name) {
	R_LOG_DEBUG ("NORMALIZE base_name=(%s) name=(%s) root=%s", base_name, name, root);
	if (r_str_startswith (name, "../")) {
	// 	return r_str_newf ("%s/%s", root, base_name + 3);
		char *newroot = strdup (root);
		const char *updir = name;
		while (r_str_startswith (updir, "../")) {
			updir = name + 3;
			const char *r = r_str_rchr (root, NULL, '/');
			if (!r) {
				break;
			}
			free (newroot); // causes an uaf
			newroot = r_str_ndup (root, r - root);
		}
		char *nr = r_str_newf ("%s/%s", newroot, updir); // base_name);
		free (newroot);
		R_LOG_DEBUG ("RELATIVE %s", nr);
		return nr;
	} else if (r_str_startswith (name, "./")) {
		if (root) {
			R_LOG_DEBUG ("HASROOT %s", root);
#if 0
			if (r_str_endswith (root, ".js")) {
				const char *r = r_str_rchr (root, NULL, '/');
				if (r) {
					// free (root); // causes an uaf
					root = r_str_ndup (root, r - root);
				}
			}
#endif
			if (r_str_startswith (name + 1, root)) {
				return strdup (name + 1);
			}
			return r_str_newf ("%s/%s", root, name + 2);
		}
		return strdup (name + 1);
	}
	// R_LOG_INFO ("normalize (%s) (%s)", base_name, name);
	return strdup (name);
}

// QuickJS releases the returned name with js_free, so it must come from js_malloc
static char *r2qjs_normalize_module_name(JSContext *ctx, const char *base_name, const char *name, void *opaque) {
	char *root = strdup (base_name);
	if (root && r_str_endswith (root, ".js")) {
		char *r = (char *)r_str_rchr (root, NULL, '/');
		if (r) {
			*r = 0;
			R_LOG_DEBUG ("USE ROOT (%s)", root);
		}
	}
	char *path = r2qjs_normalize_path (root, base_name, name);
	char *res = path? js_strdup (ctx, path): NULL;
	free (path);
	free (root);
	return res;
}

static JSModuleDef *r2qjs_load_module(JSContext *ctx, const char *module_name, void *opaque) {
	const int qjs_flags = JS_EVAL_TYPE_MODULE | JS_EVAL_FLAG_STRICT | JS_EVAL_FLAG_COMPILE_ONLY;
	R_LOG_DEBUG ("LOADING (%s)", module_name);
#if 0
	if (*module_name == '/') {
		eprintf ("RELATIVE %s\n");
		module_name = r_str_newf (".%s", module_name);
		// module_name++;
	}
#endif
	if (!strcmp (module_name, "r2papi")) {
		const char *data =  "export var R2Papi = global.R2Papi;\n"\
				    "export var R2PapiShell = global.R2PapiShell;\n"\
				    "export var NativePointer = global.NativePointer;\n"\
				    "export var EsilParser = global.EsilParser;\n"\
				    "export var EsilToken = global.EsilToken;\n"\
				    "export var r2 = global.r2;\n"\
				    "export var R = global.R;\n"\
				    ;
		JSValue val = JS_Eval (ctx, data, strlen (data), module_name,
				JS_EVAL_TYPE_MODULE | JS_EVAL_FLAG_STRICT | JS_EVAL_FLAG_COMPILE_ONLY);
		if (JS_IsException (val)) {
			JSValue e = JS_GetException (ctx);
			r2qjs_dump_obj (ctx, e);
			JS_FreeValue (ctx, e);
			return NULL;
		}
		JS_FreeValue (ctx, val);
		return JS_VALUE_GET_PTR (val);
	} else if (!strcmp (module_name, "r2pipe")) {
		const char *data =  "export function open() {\n"\
				    "  return {\n"\
				    "    cmd: r2.cmd,\n"\
				    "    cmdj: r2.cmdj,\n"\
				    "  };\n"\
				    "};\n"\
				    ;
		JSValue val = JS_Eval (ctx, data, strlen (data), module_name, qjs_flags);
		if (JS_IsException (val)) {
			JSValue e = JS_GetException (ctx);
			r2qjs_dump_obj (ctx, e);
			JS_FreeValue (ctx, e);
			return NULL;
		}
		JS_FreeValue (ctx, val);
		return JS_VALUE_GET_PTR (val);
	}
	R_LOG_DEBUG ("pop");
	HtPP *ht = opaque;
	char *data = ht? ht_pp_find (ht, module_name, NULL): NULL;
	if (data) {
#if 0
		JSModuleDef *def = JS_RunModule (ctx, "/", module_name);
		if (!def) {
			R_LOG_ERROR ("Cannot load module");
		}
		return NULL;
#else
		R_LOG_DEBUG ("MODULE %s", module_name);
		JSValue val = JS_Eval (ctx, data, strlen (data), module_name, qjs_flags);
		if (JS_IsException (val)) {
			JSValue e = JS_GetException (ctx);
			r2qjs_dump_obj (ctx, e);
			JS_FreeValue (ctx, e);
			return NULL;
		}
		JS_FreeValue (ctx, val);
		// R_LOG_INFO ("loaded (%s)", module_name);
		return JS_VALUE_GET_PTR (val);
#endif
	}
	// the loader must leave an exception behind, or QuickJS reports "[uninitialized]"
	JS_ThrowReferenceError (ctx, "could not load module '%s'", module_name);
	return NULL;
}

static void r2qjs_modules(JSContext *ctx) {
	JSRuntime *rt = JS_GetRuntime (ctx);
	JS_SetModuleLoaderFunc (rt, r2qjs_normalize_module_name, r2qjs_load_module, NULL);
}

static void free_kv_str(HtPPKv *kv) {
	free (kv->key);
	free (kv->value);
}

static int r2qjs_loader(JSContext *ctx, const char *const buffer) {
	JSRuntime *rt = JS_GetRuntime (ctx);
	if (!r_str_startswith (buffer, package_marker)) {
		return 0;
	}
	const char *ptr = buffer + strlen (package_marker);
	const char *ptr_end = buffer + strlen (buffer);
	const char *assets = strstr (ptr, delimiter_marker);
	if (!assets) {
		return -1;
	}

	HtPP *ht = ht_pp_new (NULL, free_kv_str, NULL);
	JS_SetModuleLoaderFunc (rt, r2qjs_normalize_module_name, r2qjs_load_module, ht);
	char *entry = NULL;
	char *entryfname = NULL;

	assets += strlen (delimiter_marker);
	while (ptr < ptr_end && assets < ptr_end) {
		const char * nl = strchr (ptr, '\n');
		if (!nl) {
			break;
		}
		if (r_str_nstr (ptr, alias_marker, nl - ptr)) {
			ptr = nl + 1;
			continue;
		}
		int size = atoi (ptr);
		if (size < 1) {
			break;
		}
		const char *const space = strchr (ptr, ' ');
		if (!space) {
			break;
		}
		char *filename = r_str_ndup (space + 1, nl - space - 1);
		char *data = r_str_ndup (assets, size);
		if (r_str_endswith (filename, ".js")) {
			R_LOG_DEBUG ("INSERT (%s)", filename);
			if (!entry) {
				entry = data;
				entryfname = strdup (filename);
			}
			ht_pp_insert (ht, filename, data);
		} else {
			free (data);
		}
		free (filename);
		ptr = nl + 1;
		assets += size + strlen (delimiter_marker);
	}
	if (entry) {
		R_LOG_DEBUG ("ENTRY (%s)", entryfname);
#if 0
		JSModuleDef *def = JS_RunModule (ctx, "/", entryfname);
		if (!def) {
			R_LOG_ERROR ("Cannot load module");
		}
#else
		const int qjs_flags = JS_EVAL_TYPE_GLOBAL | JS_EVAL_FLAG_STRICT | JS_EVAL_TYPE_MODULE;
		JSValue v = JS_Eval (ctx, entry, strlen (entry), entryfname, qjs_flags);
		if (JS_IsException (v)) {
			JSValue e = JS_GetException (ctx);
			r2qjs_dump_obj (ctx, e);
			JS_FreeValue (ctx, e);
		}
		JS_FreeValue (ctx, v);
#endif
	}
	free (entryfname);
	ht_pp_free (ht);
	// JS_SetModuleLoaderFunc (rt, NULL, NULL, NULL);
	JS_SetModuleLoaderFunc (rt, r2qjs_normalize_module_name, r2qjs_load_module, NULL);
	return true;
}