From caf3bb871c1a55480eef82201f458c3ac611dc65 Mon Sep 17 00:00:00 2001
From: bxaimc <bxaimc@yahoo.com>
Date: Wed, 16 May 2018 17:58:09 -0400
Subject: [PATCH] Add PSI file reading in Opus for loops in BlazBlue: Cross Tag
 Battle (Switch)

---
 src/formats.c   |  1 +
 src/meta/opus.c | 22 ++++++++++++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/formats.c b/src/formats.c
index aa893007..c0fd8336 100644
--- a/src/formats.c
+++ b/src/formats.c
@@ -250,6 +250,7 @@ static const char* extension_list[] = {
     "pos",
     "ps2stm", //fake extension for .stm (to be removed)
     "psh", // fake extension for VSV(?) Dawn of Mana needs to be checked again
+    "psi", // PSI Metadata for Opus - BlazBlue: Cross Tag Battle (Switch), Maybe others?
     "psnd",
     "psw", //fake extension for .wam
 
diff --git a/src/meta/opus.c b/src/meta/opus.c
index a120147a..60aef357 100644
--- a/src/meta/opus.c
+++ b/src/meta/opus.c
@@ -88,6 +88,7 @@ fail:
 
 /* standard Switch Opus, Nintendo header + raw data (generated by opus_test.c?) [Lego City Undercover (Switch)] */
 VGMSTREAM * init_vgmstream_opus_std(STREAMFILE *streamFile) {
+	STREAMFILE * PSIFile = NULL;
     off_t offset = 0;
     int num_samples = 0, loop_start = 0, loop_end = 0;
 
@@ -95,10 +96,23 @@ VGMSTREAM * init_vgmstream_opus_std(STREAMFILE *streamFile) {
     if (!check_extensions(streamFile,"opus,lopus"))
         goto fail;
 
-    offset = 0x00;
-    num_samples = 0;
-    loop_start = 0;
-    loop_end = 0;
+	/* BlazBlue: Cross Tag Battle (Switch) PSI Metadata for corresponding Opus */
+	/* Maybe future Arc System Works games will use this too? */
+	PSIFile = open_streamfile_by_ext(streamFile, "psi");
+
+	offset = 0x00;
+
+	if (PSIFile){
+		num_samples = read_32bitLE(0x8C, PSIFile);
+		loop_start = read_32bitLE(0x84, PSIFile);
+		loop_end = read_32bitLE(0x88, PSIFile);
+		close_streamfile(PSIFile);
+	}
+	else {
+		num_samples = 0;
+		loop_start = 0;
+		loop_end = 0;
+	}
 
     return init_vgmstream_opus(streamFile, meta_OPUS, offset, num_samples,loop_start,loop_end);
 fail: