From f0a4d1d8ec9e373e443dcaeb24110df457f70a3b Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Fri, 13 Jan 2023 21:54:59 -0500
Subject: [PATCH] Wire up did-page notifications.

---
 Machines/MSX/MSX.cpp               | 12 ++++++++++--
 Machines/MSX/MemorySlotHandler.cpp |  6 +++---
 Machines/MSX/MemorySlotHandler.hpp |  8 +++++++-
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/Machines/MSX/MSX.cpp b/Machines/MSX/MSX.cpp
index 43e910c8b..f1d0ce280 100644
--- a/Machines/MSX/MSX.cpp
+++ b/Machines/MSX/MSX.cpp
@@ -142,7 +142,8 @@ class ConcreteMachine:
 	public MachineTypes::JoystickMachine,
 	public Configurable::Device,
 	public ClockingHint::Observer,
-	public Activity::Source {
+	public Activity::Source,
+	public MSX::MemorySlotChangeHandler {
 	private:
 		static constexpr int RAMMemorySlot = 3;
 		static constexpr int RAMMemorySubSlot = 0;
@@ -163,7 +164,8 @@ class ConcreteMachine:
 			speaker_(mixer_),
 			tape_player_(3579545 * 2),
 			i8255_port_handler_(*this, audio_toggle_, tape_player_),
-			ay_port_handler_(tape_player_) {
+			ay_port_handler_(tape_player_),
+			memory_slots_{{*this}, {*this}, {*this}, {*this}} {
 			set_clock_rate(3579545);
 			clear_all_keys();
 
@@ -424,6 +426,10 @@ class ConcreteMachine:
 			update_paging();
 		}
 
+		void did_page() final {
+			update_paging();
+		}
+
 		void update_paging() {
 			uint8_t primary = primary_slots_;
 
@@ -826,6 +832,8 @@ class ConcreteMachine:
 		/// Optionally attaches non-default logic to any of the four things selectable
 		/// via the primary slot register.
 		struct MemorySlot: public MSX::MemorySlot {
+			using MSX::MemorySlot::MemorySlot;
+
 			HalfCycles cycles_since_update;
 			std::unique_ptr<MemorySlotHandler> handler;
 		};
diff --git a/Machines/MSX/MemorySlotHandler.cpp b/Machines/MSX/MemorySlotHandler.cpp
index 28f160af1..6e5f503ae 100644
--- a/Machines/MSX/MemorySlotHandler.cpp
+++ b/Machines/MSX/MemorySlotHandler.cpp
@@ -12,7 +12,7 @@
 
 using namespace MSX;
 
-MemorySlot::MemorySlot() {
+MemorySlot::MemorySlot(MemorySlotChangeHandler &handler) : handler_(handler) {
 	for(int subslot = 0; subslot < 4; subslot++) {
 		for(int region = 0; region < 8; region++) {
 			read_pointers_[subslot][region] = unmapped.data();
@@ -73,7 +73,7 @@ void MemorySlot::map(int subslot, std::size_t source_address, uint16_t destinati
 		source_address += 8192;
 	}
 
-	// TODO: need to indicate that mapping changed.
+	handler_.did_page();
 }
 
 void MemorySlot::unmap(int subslot, uint16_t destination_address, std::size_t length) {
@@ -85,7 +85,7 @@ void MemorySlot::unmap(int subslot, uint16_t destination_address, std::size_t le
 		read_pointers_[subslot][(destination_address >> 13) + c] = nullptr;
 	}
 
-	// TODO: need to indicate that mapping changed.
+	handler_.did_page();
 }
 
 template void MemorySlot::map<MSX::MemorySlot::AccessType::Read>(int subslot, std::size_t source_address, uint16_t destination_address, std::size_t length);
diff --git a/Machines/MSX/MemorySlotHandler.hpp b/Machines/MSX/MemorySlotHandler.hpp
index d20cba8a9..cac6ed032 100644
--- a/Machines/MSX/MemorySlotHandler.hpp
+++ b/Machines/MSX/MemorySlotHandler.hpp
@@ -30,9 +30,13 @@
 */
 namespace MSX {
 
+struct MemorySlotChangeHandler {
+	virtual void did_page() = 0;
+};
+
 class MemorySlot {
 	public:
-		MemorySlot();
+		MemorySlot(MemorySlotChangeHandler &);
 
 		/// Attempts to write the argument as the secondary paging selection.
 		void set_secondary_paging(uint8_t);
@@ -89,6 +93,8 @@ class MemorySlot {
 		uint8_t *write_pointers_[4][8];
 		uint8_t secondary_paging_ = 0;
 
+		MemorySlotChangeHandler &handler_;
+
 		using MemoryChunk = std::array<uint8_t, 8192>;
 		inline static MemoryChunk unmapped{0xff};
 		inline static MemoryChunk scratch;