#include "taskstub.js.h"

#include "packetstream.h"
#include "serialize.h"
#include "task.h"
#include "util.js.h"

#include <malloc.h>
#include <string.h>
#include <stdio.h>

#include "quickjs-libc.h"

#ifdef _WIN32
#include <io.h>
#include <windows.h>
#include <ws2tcpip.h>
static const int STDIN_FILENO = 0;
static const int STDOUT_FILENO = 1;
static const int STDERR_FILENO = 2;
#else
#include <unistd.h>
#endif

static JSClassID _classId;
static char _executable[1024];

typedef struct _tf_taskstub_t {
	taskid_t _id;
	JSValue _object;
	JSValue _taskObject;

	JSValue _on_exit;
	JSValue _on_error;

	tf_task_t* _owner;
	tf_packetstream_t* _stream;
	uv_process_t _process;
	bool _finalized;
} tf_taskstub_t;

void tf_taskstub_startup()
{
	static bool initialized;
	if (!initialized)
	{
		JS_NewClassID(&_classId);
		size_t size = sizeof(_executable);
		uv_exepath(_executable, &size);
		initialized = true;
	}
}

static JSValue _taskstub_activate(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_execute(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_setImports(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_getExports(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_setRequires(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_kill(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_get_on_exit(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_set_on_exit(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_get_on_error(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_set_on_error(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static JSValue _taskstub_loadFile(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv);
static void _taskstub_on_process_exit(uv_process_t* process, int64_t status, int terminationSignal);
static void _taskstub_finalizer(JSRuntime *runtime, JSValue value);

static JSValue _taskstub_create(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_task_t* parent = tf_task_get(context);
	tf_taskstub_t* stub = malloc(sizeof(tf_taskstub_t));
	memset(stub, 0, sizeof(*stub));
	stub->_stream = tf_packetstream_create();

	JSValue taskObject = JS_NewObjectClass(context, _classId);
	JS_SetOpaque(taskObject, stub);
	stub->_owner = parent;
	stub->_on_exit = JS_UNDEFINED;
	stub->_on_error = JS_UNDEFINED;
	stub->_object = JS_DupValue(context, taskObject);

	JSAtom atom = JS_NewAtom(context, "onExit");
	JS_DefinePropertyGetSet(
		context,
		taskObject,
		atom,
		JS_NewCFunction(context, _taskstub_get_on_exit, "getOnExit", 0),
		JS_NewCFunction(context, _taskstub_set_on_exit, "setOnExit", 0),
		0);
	JS_FreeAtom(context, atom);

	atom = JS_NewAtom(context, "onError");
	JS_DefinePropertyGetSet(
		context,
		taskObject,
		atom,
		JS_NewCFunction(context, _taskstub_get_on_error, "getOnError", 0),
		JS_NewCFunction(context, _taskstub_set_on_error, "setOnError", 0),
		0);
	JS_FreeAtom(context, atom);

	JS_SetPropertyStr(context, taskObject, "activate", JS_NewCFunction(context, _taskstub_activate, "activate", 0));
	JS_SetPropertyStr(context, taskObject, "execute", JS_NewCFunction(context, _taskstub_execute, "execute", 1));
	JSAtom imports = JS_NewAtom(context, "imports");
	JS_SetPropertyStr(context, taskObject, "setImports", JS_NewCFunction(context, _taskstub_setImports, "setImports", 1));
	JS_FreeAtom(context, imports);
	JS_SetPropertyStr(context, taskObject, "getExports", JS_NewCFunction(context, _taskstub_getExports, "getExports", 0));
	JS_SetPropertyStr(context, taskObject, "setRequires", JS_NewCFunction(context, _taskstub_setRequires, "setRequires", 1));
	JS_SetPropertyStr(context, taskObject, "kill", JS_NewCFunction(context, _taskstub_kill, "kill", 0));
	JS_SetPropertyStr(context, taskObject, "loadFile", JS_NewCFunction(context, _taskstub_loadFile, "loadFile", 1));

	taskid_t id = k_task_parent_id;
	if (parent)
	{
		id = tf_task_allocate_task_id(parent, (tf_taskstub_t*)stub);
	}
	stub->_id = id;

	char arg1[] = "sandbox";
	char* command_argv[] = { _executable, arg1, 0 };

	uv_pipe_t* pipe = tf_packetstream_get_pipe(stub->_stream);
	memset(pipe, 0, sizeof(*pipe));
	if (uv_pipe_init(tf_task_get_loop(parent), pipe, 1) != 0)
	{
		fprintf(stderr, "uv_pipe_init failed\n");
	}

	uv_stdio_container_t io[3];
	io[0].flags = UV_CREATE_PIPE | UV_READABLE_PIPE | UV_WRITABLE_PIPE;
	io[0].data.stream = (uv_stream_t*)pipe;
	io[1].flags = UV_INHERIT_FD;
	io[1].data.fd = STDOUT_FILENO;
	io[2].flags = UV_INHERIT_FD;
	io[2].data.fd = STDERR_FILENO;

	uv_process_options_t options = {0};
	options.args = command_argv;
	options.exit_cb = _taskstub_on_process_exit;
	options.stdio = io;
	options.stdio_count = sizeof(io) / sizeof(*io);
	options.file = command_argv[0];

	JSValue result = JS_NULL;
	stub->_process.data = stub;
	int spawn_result = uv_spawn(tf_task_get_loop(parent), &stub->_process, &options);
	if (spawn_result == 0)
	{
		tf_packetstream_set_on_receive(stub->_stream, tf_task_on_receive_packet, stub);
		tf_packetstream_start(stub->_stream);

		result = taskObject;
	}
	else
	{
		fprintf(stderr, "uv_spawn failed: %s\n", uv_strerror(spawn_result));
		JS_FreeValue(context, taskObject);
	}
	return result;
}

void _taskstub_gc_mark(JSRuntime* rt, JSValueConst value, JS_MarkFunc mark_func)
{
	tf_taskstub_t* stub = JS_GetOpaque(value, _classId);
	if (stub)
	{
		JS_MarkValue(rt, stub->_on_exit, mark_func);
		JS_MarkValue(rt, stub->_on_error, mark_func);
	}
}

JSValue tf_taskstub_register(JSContext* context)
{
	JSClassDef def = {
		.class_name = "TaskStub",
		.finalizer = &_taskstub_finalizer,
		.gc_mark = _taskstub_gc_mark,
	};
	if (JS_NewClass(JS_GetRuntime(context), _classId, &def) != 0)
	{
		fprintf(stderr, "Failed to register TaskStub class.\n");
	}
	return JS_NewCFunction2(context, _taskstub_create, "TaskStub", 0, JS_CFUNC_constructor, 0);
}

taskid_t tf_taskstub_get_id(const tf_taskstub_t* stub)
{
	return stub->_id;
}

JSValue tf_taskstub_get_task_object(const tf_taskstub_t* stub)
{
	return stub->_taskObject;
}

tf_packetstream_t* tf_taskstub_get_stream(const tf_taskstub_t* stub)
{
	return stub->_stream;
}

tf_task_t* tf_taskstub_get_owner(const tf_taskstub_t* stub)
{
	return stub->_owner;
}

tf_taskstub_t* tf_taskstub_create_parent(tf_task_t* task, uv_file file)
{
	JSValue parentObject = JS_NewObject(tf_task_get_context(task));
	tf_taskstub_t* parentStub = malloc(sizeof(tf_taskstub_t));
	memset(parentStub, 0, sizeof(tf_taskstub_t));
	parentStub->_stream = tf_packetstream_create();
	parentStub->_on_exit = JS_UNDEFINED;
	parentStub->_on_error = JS_UNDEFINED;

	parentStub->_taskObject = parentObject;
	JS_SetOpaque(parentObject, parentStub);
	parentStub->_owner = task;
	parentStub->_id = k_task_parent_id;
	parentStub->_object = JS_DupValue(tf_task_get_context(task), parentObject);

	if (uv_pipe_init(tf_task_get_loop(task), tf_packetstream_get_pipe(parentStub->_stream), 1) != 0)
	{
		fprintf(stderr, "uv_pipe_init failed\n");
	}
	tf_packetstream_set_on_receive(parentStub->_stream, tf_task_on_receive_packet, parentStub);
	if (uv_pipe_open(tf_packetstream_get_pipe(parentStub->_stream), file) != 0)
	{
		fprintf(stderr, "uv_pipe_open failed\n");
	}
	tf_packetstream_start(parentStub->_stream);

	return parentStub;
}

static void _taskstub_cleanup(tf_taskstub_t* stub)
{
	if (!stub->_process.data &&
		JS_IsUndefined(stub->_object) &&
		stub->_finalized)
	{
		free(stub);
	}
}

static void _taskstub_finalizer(JSRuntime* runtime, JSValue value)
{
	tf_taskstub_t* stub = JS_GetOpaque(value, _classId);
	stub->_on_exit = JS_UNDEFINED;
	stub->_on_error = JS_UNDEFINED;
	tf_packetstream_destroy(stub->_stream);
	stub->_stream = NULL;
	stub->_finalized = true;
	tf_task_remove_child(stub->_owner, stub);
	_taskstub_cleanup(stub);
}

static void _taskstub_on_handle_close(uv_handle_t* handle)
{
	tf_taskstub_t* stub = handle->data;
	handle->data = NULL;
	tf_task_remove_child(stub->_owner, stub);
	_taskstub_cleanup(stub);
}

static void _taskstub_on_process_exit(uv_process_t* process, int64_t status, int terminationSignal)
{
	tf_taskstub_t* stub = process->data;
	JSContext* context = tf_task_get_context(stub->_owner);
	if (!JS_IsUndefined(stub->_on_exit))
	{
		JSValue argv[] = { JS_NewInt32(context, status), JS_NewInt32(context, terminationSignal) };
		JSValue result = JS_Call(context, stub->_on_exit, JS_NULL, 2, argv);
		tf_util_report_error(context, result);
		JS_FreeValue(context, result);
		tf_task_run_jobs(stub->_owner);
		JS_FreeValue(context, argv[0]);
		JS_FreeValue(context, argv[1]);
	}
	tf_packetstream_close(stub->_stream);
	uv_close((uv_handle_t*)process, _taskstub_on_handle_close);
	tf_taskstub_destroy(stub);
}

static JSValue _taskstub_getExports(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	promiseid_t promise = tf_task_allocate_promise(stub->_owner);
	tf_task_send_promise_message(stub->_owner, (tf_taskstub_t*)stub, kGetExports, promise, JS_UNDEFINED);
	return tf_task_get_promise(stub->_owner, promise);
}

static JSValue _taskstub_setImports(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	void* buffer;
	size_t size;
	tf_serialize_store(tf_task_get(context), stub, &buffer, &size, argv[0]);
	tf_packetstream_send(stub->_stream, kSetImports, (char*)buffer, size);
	return JS_UNDEFINED;
}

static JSValue _taskstub_setRequires(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	void* buffer;
	size_t size;
	tf_serialize_store(tf_task_get(context), stub, &buffer, &size, argv[0]);
	tf_packetstream_send(stub->_stream, kSetRequires, (char*)buffer, size);
	return JS_UNDEFINED;
}

static JSValue _taskstub_loadFile(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	void* buffer;
	size_t size;
	tf_serialize_store(tf_task_get(context), stub, &buffer, &size, argv[0]);
	tf_packetstream_send(stub->_stream, kLoadFile, (char*)buffer, size);
	return JS_UNDEFINED;
}

static JSValue _taskstub_get_on_exit(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	return JS_DupValue(context, stub->_on_exit);
}

static JSValue _taskstub_set_on_exit(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	if (!JS_IsUndefined(stub->_on_exit))
	{
		JS_FreeValue(context, stub->_on_exit);
	}
	stub->_on_exit = JS_DupValue(context, argv[0]);
	return JS_UNDEFINED;
}

static JSValue _taskstub_get_on_error(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	return JS_DupValue(context, stub->_on_error);
}

static JSValue _taskstub_set_on_error(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	if (!JS_IsUndefined(stub->_on_error))
	{
		JS_FreeValue(context, stub->_on_error);
	}
	stub->_on_error = JS_DupValue(context, argv[0]);
	return JS_UNDEFINED;
}

static JSValue _taskstub_activate(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	if (stub)
	{
		tf_packetstream_send(stub->_stream, kActivate, 0, 0);
	}
	return JS_NULL;
}

static JSValue _taskstub_execute(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	promiseid_t promise = tf_task_allocate_promise(stub->_owner);
	tf_task_send_promise_message(stub->_owner, (tf_taskstub_t*)stub, kExecute, promise, argv[0]);
	return tf_task_get_promise(stub->_owner, promise);
}

static JSValue _taskstub_kill(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_taskstub_t* stub = JS_GetOpaque(this_val, _classId);
	uv_process_kill(&stub->_process, SIGTERM);
	return JS_UNDEFINED;
}

void tf_taskstub_destroy(tf_taskstub_t* stub)
{
	if (!JS_IsUndefined(stub->_object))
	{
		JSValue object = stub->_object;
		stub->_object = JS_UNDEFINED;
		JS_FreeValue(tf_task_get_context(stub->_owner), object);
	}
}

void tf_taskstub_on_error(tf_taskstub_t* stub, JSValue error)
{
	JSContext* context = tf_task_get_context(stub->_owner);
	if (!JS_IsUndefined(stub->_on_error))
	{
		JSValue result = JS_Call(context, stub->_on_error, JS_NULL, 1, &error);
		tf_util_report_error(context, result);
		JS_FreeValue(context, result);
		tf_task_run_jobs(stub->_owner);
	}
}