From 956335e844324a398a0c6a21c5d04d85c2f7999e Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Wed, 17 Apr 2024 15:00:14 +0300
Subject: [PATCH] Kernel: Implement AML WhileOp

---
 kernel/include/kernel/ACPI/AML/While.h | 65 ++++++++++++++++++++++++++
 kernel/kernel/ACPI/AML/Node.cpp        |  3 ++
 2 files changed, 68 insertions(+)
 create mode 100644 kernel/include/kernel/ACPI/AML/While.h

diff --git a/kernel/include/kernel/ACPI/AML/While.h b/kernel/include/kernel/ACPI/AML/While.h
new file mode 100644
index 00000000..19c0bf3b
--- /dev/null
+++ b/kernel/include/kernel/ACPI/AML/While.h
@@ -0,0 +1,65 @@
+#pragma once
+
+#include <kernel/ACPI/AML/Node.h>
+#include <kernel/ACPI/AML/ParseContext.h>
+#include <kernel/ACPI/AML/Pkg.h>
+
+namespace Kernel::ACPI::AML
+{
+
+	struct While
+	{
+		static ParseResult parse(ParseContext& context)
+		{
+			ASSERT(context.aml_data.size() >= 1);
+			ASSERT(static_cast<Byte>(context.aml_data[0]) == Byte::WhileOp);
+			context.aml_data = context.aml_data.slice(1);
+
+			auto while_pkg = AML::parse_pkg(context.aml_data);
+			if (!while_pkg.has_value())
+				return ParseResult::Failure;
+
+			auto outer_aml_data = context.aml_data;
+
+			bool breaked = false;
+			while (!breaked)
+			{
+				context.aml_data = while_pkg.value();
+
+				auto predicate_result = AML::parse_object(context);
+				if (!predicate_result.success())
+					return ParseResult::Failure;
+				auto predicate = predicate_result.node() ? predicate_result.node()->as_integer() : BAN::Optional<uint64_t>();
+				if (!predicate.has_value())
+				{
+					AML_ERROR("While predicate is not an integer");
+					return ParseResult::Failure;
+				}
+
+				if (!predicate.value())
+					break;
+
+				while (context.aml_data.size() > 0)
+				{
+					// NOTE: we can just parse BreakOp here, since this is the only legal place for BreakOp
+					if (static_cast<AML::Byte>(context.aml_data[0]) == AML::Byte::BreakOp)
+					{
+						context.aml_data = context.aml_data.slice(1);
+						breaked = true;
+						break;
+					}
+					auto object_result = AML::parse_object(context);
+					if (object_result.returned())
+						return ParseResult(ParseResult::Result::Returned, object_result.node());
+					if (!object_result.success())
+						return ParseResult::Failure;
+				}
+			}
+
+			context.aml_data = outer_aml_data;
+
+			return ParseResult::Success;
+		}
+	};
+
+}
diff --git a/kernel/kernel/ACPI/AML/Node.cpp b/kernel/kernel/ACPI/AML/Node.cpp
index 227399e7..640cb00a 100644
--- a/kernel/kernel/ACPI/AML/Node.cpp
+++ b/kernel/kernel/ACPI/AML/Node.cpp
@@ -21,6 +21,7 @@
 #include <kernel/ACPI/AML/String.h>
 #include <kernel/ACPI/AML/ThermalZone.h>
 #include <kernel/ACPI/AML/Utils.h>
+#include <kernel/ACPI/AML/While.h>
 
 namespace Kernel::ACPI
 {
@@ -163,6 +164,8 @@ namespace Kernel::ACPI
 				return AML::Scope::parse(context);
 			case AML::Byte::IfOp:
 				return AML::IfElse::parse(context);
+			case AML::Byte::WhileOp:
+				return AML::While::parse(context);
 			case AML::Byte::StoreOp:
 				return AML::Store::parse(context);
 			case AML::Byte::DerefOfOp: