From 767e8f08e0fc5054c9b1dad2e033116fb633b4dc Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <mclaughc@outlook.com>
Date: Thu, 26 Sep 2019 00:15:06 +1000
Subject: [PATCH] CDROM: Move pregap handling to image class

---
 src/common/cd_image.cpp | 11 ++++++-----
 src/common/cd_image.h   |  7 +++++--
 src/pse/cdrom.cpp       |  4 ++--
 3 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/common/cd_image.cpp b/src/common/cd_image.cpp
index 7841c18bc..b3cc635ea 100644
--- a/src/common/cd_image.cpp
+++ b/src/common/cd_image.cpp
@@ -11,14 +11,15 @@ CDImage::~CDImage()
     m_data_file->Release();
 }
 
-constexpr u64 CDImage::MSFToLBA(u32 minute, u32 second, u32 frame)
+constexpr u64 CDImage::MSFToLBA(u32 pregap_seconds, u32 minute, u32 second, u32 frame)
 {
-  return ZeroExtend64(minute) * FRAMES_PER_MINUTE + ZeroExtend64(second) * FRAMES_PER_SECOND + ZeroExtend64(frame);
+  return ZeroExtend64(minute) * FRAMES_PER_MINUTE + ZeroExtend64(second) * FRAMES_PER_SECOND + ZeroExtend64(frame) -
+         ZeroExtend64(pregap_seconds) * FRAMES_PER_SECOND;
 }
 
-constexpr void CDImage::LBAToMSF(u64 lba, u32* minute, u32* second, u32* frame)
+constexpr void CDImage::LBAToMSF(u32 pregap_seconds, u64 lba, u32* minute, u32* second, u32* frame)
 {
-  const u32 offset = lba % FRAMES_PER_MINUTE;
+  const u64 offset = (lba + (pregap_seconds * FRAMES_PER_SECOND) % FRAMES_PER_MINUTE);
   *minute = Truncate32(lba / FRAMES_PER_MINUTE);
   *second = Truncate32(offset / FRAMES_PER_SECOND);
   *frame = Truncate32(offset % FRAMES_PER_SECOND);
@@ -52,7 +53,7 @@ bool CDImage::Seek(u64 lba)
 
 bool CDImage::Seek(u32 minute, u32 second, u32 frame)
 {
-  return Seek(MSFToLBA(minute, second, frame));
+  return Seek(MSFToLBA(m_pregap_seconds, minute, second, frame));
 }
 
 u32 CDImage::Read(ReadMode read_mode, u64 lba, u32 sector_count, void* buffer)
diff --git a/src/common/cd_image.h b/src/common/cd_image.h
index 3bcfe1ae1..f27c78f51 100644
--- a/src/common/cd_image.h
+++ b/src/common/cd_image.h
@@ -27,8 +27,8 @@ public:
   };
 
   // Conversion helpers.
-  static constexpr u64 MSFToLBA(u32 minute, u32 second, u32 frame);
-  static constexpr void LBAToMSF(u64 lba, u32* minute, u32* second, u32* frame);
+  static constexpr u64 MSFToLBA(u32 pregap_seconds, u32 minute, u32 second, u32 frame);
+  static constexpr void LBAToMSF(u32 pregap_seconds, u64 lba, u32* minute, u32* second, u32* frame);
 
   // Accessors.
   u64 GetCurrentLBA() const { return m_current_lba; }
@@ -53,6 +53,9 @@ private:
   // TODO: Multiple data files from cue sheet
   ByteStream* m_data_file = nullptr;
 
+  // Pregap size.
+  u32 m_pregap_seconds = 2;
+
   // Current LBA/total LBAs.
   u64 m_current_lba = 0;
   u64 m_lba_count = 0;
diff --git a/src/pse/cdrom.cpp b/src/pse/cdrom.cpp
index 4853a90df..49c1d3c2a 100644
--- a/src/pse/cdrom.cpp
+++ b/src/pse/cdrom.cpp
@@ -565,7 +565,7 @@ void CDROM::ExecuteCommand()
       {
         Assert(m_setloc_dirty);
         StopReading();
-        if (!m_media || !m_media->Seek(m_setloc.minute, m_setloc.second - 2 /* pregap */, m_setloc.frame))
+        if (!m_media || !m_media->Seek(m_setloc.minute, m_setloc.second, m_setloc.frame))
         {
           Panic("Error in Setloc command");
           return;
@@ -619,7 +619,7 @@ void CDROM::ExecuteCommand()
       // TODO: Seek timing and clean up...
       if (m_setloc_dirty)
       {
-        if (!m_media || !m_media->Seek(m_setloc.minute, m_setloc.second - 2 /* pregap */, m_setloc.frame))
+        if (!m_media || !m_media->Seek(m_setloc.minute, m_setloc.second, m_setloc.frame))
         {
           Panic("Seek error");
         }