#include "util.js.h"

#include "mem.h"
#include "task.h"
#include "trace.h"

#include <base64c.h>
#include <picohttpparser.h>
#include <quickjs-libc.h>
#include <uv.h>

#include <string.h>

static JSValue _util_utf8_encode(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	size_t length = 0;
	const char* value = JS_ToCStringLen(context, &length, argv[0]);
	JSValue arrayBuffer = JS_NewArrayBufferCopy(context, (const uint8_t*)value, length);
	JSValue global = JS_GetGlobalObject(context);
	JSValue constructor = JS_GetPropertyStr(context, global, "Uint8Array");
	JS_FreeValue(context, global);
	JSValue typedArray = JS_CallConstructor(context, constructor, 1, &arrayBuffer);
	JS_FreeValue(context, constructor);
	JS_FreeValue(context, arrayBuffer);
	JS_FreeCString(context, value);
	return typedArray;
}

static JSValue _util_utf8_decode(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_NULL;
	size_t length;
	if (JS_IsString(argv[0]))
	{
		result = JS_DupValue(context, argv[0]);
	}
	else
	{
		uint8_t* array = tf_util_try_get_array_buffer(context, &length, argv[0]);
		if (array)
		{
			result = JS_NewStringLen(context, (const char*)array, length);
		}
		else
		{
			size_t offset;
			size_t element_size;
			JSValue buffer = tf_util_try_get_typed_array_buffer(context, argv[0], &offset, &length, &element_size);
			size_t size;
			if (!JS_IsException(buffer))
			{
				array = tf_util_try_get_array_buffer(context, &size, buffer);
				if (array)
				{
					result = JS_NewStringLen(context, (const char*)array, size);
				}
			}
			JS_FreeValue(context, buffer);
		}
	}
	return result;
}

JSValue tf_util_utf8_decode(JSContext* context, JSValue value)
{
	return _util_utf8_decode(context, JS_NULL, 1, &value);
}

static JSValue _util_base64_encode(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	size_t length = 0;
	const char* value = JS_ToCStringLen(context, &length, argv[0]);
	char* encoded = tf_malloc(length * 4);

	int r = base64c_encode((const uint8_t*)value, length, (uint8_t*)encoded, length * 4);
	if (r >= 0)
	{
		result = JS_NewStringLen(context, encoded, r);
	}

	tf_free(encoded);
	JS_FreeCString(context, value);
	return result;
}

static JSValue _util_base64_decode(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	size_t length = 0;
	const char* value = JS_ToCStringLen(context, &length, argv[0]);
	char* encoded = tf_malloc(length);

	int r = base64c_decode((const uint8_t*)value, length, (uint8_t*)encoded, length);
	if (r >= 0)
	{
		result = JS_NewStringLen(context, encoded, r);
	}

	tf_free(encoded);
	JS_FreeCString(context, value);
	return result;
}

uint8_t* tf_util_try_get_array_buffer(JSContext* context, size_t* psize, JSValueConst obj)
{
	uint8_t* result = JS_GetArrayBuffer(context, psize, obj);
	JS_FreeValue(context, JS_GetException(context));
	return result;
}

JSValue tf_util_try_get_typed_array_buffer(JSContext* context, JSValueConst obj, size_t* pbyte_offset, size_t* pbyte_length, size_t* pbytes_per_element)
{
	JSValue result = JS_GetTypedArrayBuffer(context, obj, pbyte_offset, pbyte_length, pbytes_per_element);
	JS_FreeValue(context, JS_GetException(context));
	return result;
}

JSValue _util_print(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_task_t* task = JS_GetContextOpaque(context);
	if (task)
	{
		printf("Task[%p:%s]>", task, tf_task_get_name(task));
		tf_task_print(task, argc, argv);
	}
	for (int i = 0; i < argc; ++i)
	{
		if (JS_IsNull(argv[i]))
		{
			printf(" null");
		}
		else
		{
			const char* value = JS_ToCString(context, argv[i]);
			printf(" %s", value);
			JS_FreeCString(context, value);
		}
	}
	printf("\n");
	return JS_NULL;
}

bool tf_util_report_error(JSContext* context, JSValue value)
{
	bool is_error = false;
	if (JS_IsError(context, value))
	{
		const char* string = JS_ToCString(context, value);
		printf("ERROR: %s\n", string);
		JS_FreeCString(context, string);

		JSValue stack = JS_GetPropertyStr(context, value, "stack");
		if (!JS_IsUndefined(stack))
		{
			const char* stack_str = JS_ToCString(context, stack);
			printf("%s\n", stack_str);
			JS_FreeCString(context, stack_str);
		}
		JS_FreeValue(context, stack);

		tf_task_t* task = tf_task_get(context);
		if (!task || !tf_task_send_error_to_parent(task, value))
		{
			js_std_dump_error(context);
		}
		is_error = true;
	}
	else if (JS_IsException(value))
	{
		tf_task_t* task = tf_task_get(context);
		if (!task || !tf_task_send_error_to_parent(task, value))
		{
			js_std_dump_error(context);
		}
		is_error = true;
	}
	return is_error;
}

typedef struct _timeout_t {
	tf_task_t* _task;
	JSValue _callback;
} timeout_t;

static void _handle_closed(uv_handle_t* handle)
{
	tf_free(handle);
}

static void _util_timeoutCallback(uv_timer_t* handle)
{
	timeout_t* timeout = handle->data;
	tf_trace_begin(tf_task_get_trace(timeout->_task), "_util_timeoutCallback");
	JSContext* context = tf_task_get_context(timeout->_task);
	JSValue result = JS_Call(
		context,
		timeout->_callback,
		JS_NULL,
		0,
		NULL);
	tf_util_report_error(context, result);
	JS_FreeValue(context, result);
	JS_FreeValue(context, timeout->_callback);
	tf_trace_end(tf_task_get_trace(timeout->_task));
	tf_free(timeout);
	uv_close((uv_handle_t*)handle, _handle_closed);
}

static JSValue _util_setTimeout(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	tf_task_t* task = JS_GetContextOpaque(context);

	timeout_t* timeout = tf_malloc(sizeof(timeout_t));
	*timeout = (timeout_t)
	{
		._task = task,
		._callback = JS_DupValue(context, argv[0]),
	};

	uv_timer_t* timer = tf_malloc(sizeof(uv_timer_t));
	memset(timer, 0, sizeof(uv_timer_t));
	uv_timer_init(tf_task_get_loop(task), timer);
	timer->data = timeout;

	int64_t duration;
	JS_ToInt64(context, &duration, argv[1]);
	uv_timer_start(timer, _util_timeoutCallback, duration, 0);
	return JS_NULL;
}

static JSValue _util_parseHttp(JSContext* context, JSValueConst this_val, int argc, JSValueConst* argv)
{
	JSValue result = JS_UNDEFINED;
	const char* method = NULL;
	size_t method_length = 0;
	const char* path = NULL;
	size_t path_length = 0;
	int minor_version = 0;
	struct phr_header headers[100];
	size_t header_count = sizeof(headers) / sizeof(*headers);
	int previous_length = 0;
	JS_ToInt32(context, &previous_length, argv[1]);

	JSValue buffer = JS_UNDEFINED;
	size_t length;
	uint8_t* array = tf_util_try_get_array_buffer(context, &length, argv[0]);
	if (!array)
	{
		size_t offset;
		size_t element_size;
		buffer = tf_util_try_get_typed_array_buffer(context, argv[0], &offset, &length, &element_size);
		if (!JS_IsException(buffer))
		{
			array = tf_util_try_get_array_buffer(context, &length, buffer);
		}
	}

	if (array)
	{
		int parse_result = phr_parse_request((const char*)array, length, &method, &method_length, &path, &path_length, &minor_version, headers, &header_count, 0);
		if (parse_result > 0)
		{
			result = JS_NewObject(context);
			JS_SetPropertyStr(context, result, "bytes_parsed", JS_NewInt32(context, parse_result));
			JS_SetPropertyStr(context, result, "minor_version", JS_NewInt32(context, minor_version));
			JS_SetPropertyStr(context, result, "method", JS_NewStringLen(context, method, method_length));
			JS_SetPropertyStr(context, result, "path", JS_NewStringLen(context, path, path_length));
			JSValue header_object = JS_NewObject(context);
			for (int i = 0; i < (int)header_count; i++)
			{
				char name[256];
				snprintf(name, sizeof(name), "%.*s", (int)headers[i].name_len, headers[i].name);
				JS_SetPropertyStr(context, header_object, name, JS_NewStringLen(context, headers[i].value, headers[i].value_len));
			}
			JS_SetPropertyStr(context, result, "headers", header_object);
		}
		else
		{
			result = JS_NewInt32(context, parse_result);
		}
	}
	else
	{
		result = JS_ThrowTypeError(context, "Could not convert argument to array.");
	}

	JS_FreeValue(context, buffer);

	return result;

}

void tf_util_register(JSContext* context)
{
	JSValue global = JS_GetGlobalObject(context);
	JS_SetPropertyStr(context, global, "utf8Decode", JS_NewCFunction(context, _util_utf8_decode, "utf8Decode", 1));
	JS_SetPropertyStr(context, global, "utf8Encode", JS_NewCFunction(context, _util_utf8_encode, "utf8Encode", 1));
	JS_SetPropertyStr(context, global, "base64Decode", JS_NewCFunction(context, _util_base64_decode, "base64Decode", 1));
	JS_SetPropertyStr(context, global, "base64Encode", JS_NewCFunction(context, _util_base64_encode, "base64Encode", 1));
	JS_SetPropertyStr(context, global, "print", JS_NewCFunction(context, _util_print, "print", 1));
	JS_SetPropertyStr(context, global, "setTimeout", JS_NewCFunction(context, _util_setTimeout, "setTimeout", 2));
	JS_SetPropertyStr(context, global, "parseHttp", JS_NewCFunction(context, _util_parseHttp, "parseHttp", 2));
	JS_FreeValue(context, global);
}

int tf_util_get_length(JSContext* context, JSValue value)
{
	JSValue length = JS_GetPropertyStr(context, value, "length");
	int result = 0;
	JS_ToInt32(context, &result, length);
	JS_FreeValue(context, length);
	return result;
}

int tf_util_insert_index(const void* key, const void* base, size_t count, size_t size, int (*compare)(const void*, const void*))
{
	int lower = 0;
	int upper = count;
	while (lower < upper && lower < (int)count)
	{
		int guess = (lower + upper) / 2;
		int result = compare(key, ((char*)base) + size * guess);
		if (result < 0)
		{
			upper = guess;
		}
		else if (result > 0)
		{
			lower = guess + 1;
		}
		else
		{
			return guess;
		}
	};
	return lower;
}