From a3e55c20c83f933f7619cac9dd6538487fd8846c Mon Sep 17 00:00:00 2001
From: Steve Ayerhart <steve@ayerh.art>
Date: Tue, 31 Mar 2020 09:54:05 -0500
Subject: [PATCH] wip

---
 extra/flac/decoder/decoder.factor | 25 +++++++++++++++--------
 extra/flac/format/format.factor   | 34 +++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 9 deletions(-)

diff --git a/extra/flac/decoder/decoder.factor b/extra/flac/decoder/decoder.factor
index b5a628027b..5474921339 100644
--- a/extra/flac/decoder/decoder.factor
+++ b/extra/flac/decoder/decoder.factor
@@ -140,9 +140,14 @@ ERROR: invalid-subframe-sync ;
     } cond <flac-subframe-type> ;
 
 
-: read-constant-subframe ( bps -- data )
-    8 / read ;
+: read-constant-subframe ( subframe-header frame-header -- data )
+    >>bits-per-sample 8 / read swap drop ;
 
+: read-fixed-subframe ( predictive-order -- subframe )
+    drop 9 ;
+
+: read-lpc-subframe ( predictive-order -- subframe )
+    drop 9 ;
 
 :: decode-subframe-header ( bitstream -- subframe )
     1 bitstream read-bit 1 = [ invalid-subframe-sync ] when
@@ -153,14 +158,16 @@ ERROR: invalid-subframe-sync ;
 ! TODO: actually decode based on subframe type
 ! TODO: handle wasted bits assuming 1 byte for now :/
 : read-subframe ( frame-header -- subframe )
-    1 read bitstreams:<msb0-bit-reader> decode-subframe-header dup
+    [
+        1 read bitstreams:<msb0-bit-reader> decode-subframe-header dup
+    ] dip swap
     subframe-type>>
     {
-        { subframe-type-constant [ swap bits-per-sample>> read-constant-subframe ] }
-        { subframe-type-verbatim [ drop "VERBATIM TODO" . B{ } ] }
-        { subframe-type-fixed [ drop "FIXED TODO" . B{ } ] }
-        { subframe-type-lpc [ drop "LPC TODO" . B{ } ] }
-    } case 
+        { subframe-type-constant [ "1" ] }
+        { subframe-type-verbatim [ drop drop B{ } ] }
+        { subframe-type-fixed [ drop drop B{ } ] }
+        { subframe-type-lpc [ drop drop B{ } ] }
+    } case
     flac-subframe boa ;
 
 : read-subframes ( frame-header -- seq )
@@ -178,7 +185,7 @@ ERROR: invalid-subframe-sync ;
     read-frame-footer
     flac-frame boa ;
 
-: decode-file ( filename -- something )
+: read-flac-file ( filename -- something )
     binary
     [
         read-flac-magic [ not-a-flac-file ] unless
diff --git a/extra/flac/format/format.factor b/extra/flac/format/format.factor
index d6eac54e81..e3d860fb37 100644
--- a/extra/flac/format/format.factor
+++ b/extra/flac/format/format.factor
@@ -4,6 +4,20 @@ USING: alien.syntax math byte-arrays sequences ;
 
 IN: flac.format
 
+CONSTANT: MIN-BLOCK-SIZE 16
+CONSTANT: MAX-BLOCK-SIZE 65535
+CONSTANT: MAX-SAMPLE-SIZE: 4608
+CONSTANT: MAX-CHANNELS 8
+CONSTANT: MIN-BITS-PER-SAMPLE 4
+CONSTANT: MAX-BITS-PER-SAMPLE 32 ! The value is ((2^16) - 1) * 10
+CONSTANT: MAX-LPC-ORDER 32
+CONSTANT: MAX-LPC-ORDER-48000HZ 12
+CONSTANT: MIN-QLP-COEFF-PRECISION 5
+CONSTANT: MAX-QLP-COEEF-PRECISION 15
+CONSTANT: MAX-FIXED-ORDER 4
+CONSTANT: MAX-RICE-PARTITION-ORDER 15
+
+
 ENUM: flac-frame-number-type
     frame-number-type-frame
     frame-number-type-sample ;
@@ -63,6 +77,26 @@ ENUM: flac-entropy-coding-method
     entropy-coding-partioned-rice
     entropy-coding-partioned-rice2 ;
 
+TUPLE: partition
+    { encoding-parameter integer }
+    { partitions sequence } ;
+
+TUPLE: residual
+    method
+    { partition partition }
+
+TUPLE: subframe-constant
+    { value integer } ;
+
+TUPLE: subframe-verbatim
+    { data byte-array } ;
+
+TUPLE: subframe-fixed
+     entropy-coding-method
+    { order integer }
+    { warmup integer }
+    residual ;
+
 TUPLE: flac-frame-footer
     { crc integer } ;