From 1177ef6f8d8ee382c8446a18bd1ac35aef209305 Mon Sep 17 00:00:00 2001
From: David Given <dg@cowlark.com>
Date: Tue, 3 Aug 2021 22:31:33 +0200
Subject: [PATCH] Allow the LDBS data rate and recording mode to be specified,
 or (crudely) guessed if not.

---
 lib/imagewriter/imagewriter.proto  | 24 +++++++++++++++++++++++-
 lib/imagewriter/ldbsimagewriter.cc | 22 +++++++++++++++++++---
 2 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/lib/imagewriter/imagewriter.proto b/lib/imagewriter/imagewriter.proto
index 6561b431..6585e026 100644
--- a/lib/imagewriter/imagewriter.proto
+++ b/lib/imagewriter/imagewriter.proto
@@ -4,7 +4,29 @@ import "lib/imagereader/imagereader.proto";
 import "lib/common.proto";
 
 message D64OutputProto {}
-message LDBSOutputProto {}
+
+message LDBSOutputProto {
+	enum DataRate {
+		RATE_HD = 0;
+		RATE_DD = 1;
+		RATE_SD = 2;
+		RATE_ED = 3;
+		RATE_GUESS = -1;
+	}
+
+	enum RecordingMode {
+		RECMODE_MFM = 0;
+		RECMODE_FM = 1;
+		RECMODE_GCR_MAC = 0x12;
+		RECMODE_GCR_PRODOS = 0x14;
+		RECMODE_GCR_LISA = 0x22;
+		RECMODE_GUESS = -1;
+	}
+
+	optional DataRate data_rate = 1 [default=RATE_GUESS, (help) = "data rate to use in LDBS file"];
+	optional RecordingMode recording_mode = 2 [default=RECMODE_GUESS, (help) = "recording mode to use in LDBS file"];
+}
+
 message DiskCopyOutputProto {}
 message NsiOutputProto {}
 
diff --git a/lib/imagewriter/ldbsimagewriter.cc b/lib/imagewriter/ldbsimagewriter.cc
index 71ed390b..89923a37 100644
--- a/lib/imagewriter/ldbsimagewriter.cc
+++ b/lib/imagewriter/ldbsimagewriter.cc
@@ -23,7 +23,7 @@ public:
 
 		const Geometry geometry = image.getGeometry();
 
-		std::cout << fmt::format("writing {} tracks, {} sides, {} sectors, {} bytes per sector",
+		std::cout << fmt::format("LDBS: writing {} tracks, {} sides, {} sectors, {} bytes per sector",
 						geometry.numTracks, geometry.numSides, geometry.numSectors,
 						geometry.sectorSize)
 				<< std::endl;
@@ -33,6 +33,22 @@ public:
         int trackDirectorySize = 0;
         trackDirectoryWriter.write_le16(0);
 
+		LDBSOutputProto::DataRate dataRate = _config.ldbs().data_rate();
+		if (dataRate == LDBSOutputProto::RATE_GUESS)
+		{
+			dataRate = (geometry.numSectors > 10) ? LDBSOutputProto::RATE_HD : LDBSOutputProto::RATE_DD;
+			if (geometry.sectorSize <= 256)
+				dataRate = LDBSOutputProto::RATE_SD;
+			std::cout << fmt::format("LDBS: guessing data rate as {}\n", LDBSOutputProto::DataRate_Name(dataRate));
+		}
+
+		LDBSOutputProto::RecordingMode recordingMode = _config.ldbs().recording_mode();
+		if (recordingMode == LDBSOutputProto::RECMODE_GUESS)
+		{
+			recordingMode = LDBSOutputProto::RECMODE_MFM;
+			std::cout << fmt::format("LDBS: guessing recording mode as {}\n", LDBSOutputProto::RecordingMode_Name(recordingMode));
+		}
+
 		for (int track = 0; track < geometry.numTracks; track++)
 		{
 			for (int side = 0; side < geometry.numSides; side++)
@@ -51,8 +67,8 @@ public:
                 trackHeaderWriter.write_le16(0x000C); /* offset of sector sideers */
                 trackHeaderWriter.write_le16(0x0012); /* length of each sector descriptor */
                 trackHeaderWriter.write_le16(actualSectors);
-                trackHeaderWriter.write_8(0); /* data rate unknown */
-                trackHeaderWriter.write_8(0); /* recording mode unknown */
+                trackHeaderWriter.write_8(dataRate);
+                trackHeaderWriter.write_8(recordingMode);
                 trackHeaderWriter.write_8(0); /* format gap length */
                 trackHeaderWriter.write_8(0); /* filler byte */
                 trackHeaderWriter.write_le16(0); /* approximate track length */