From 75789de56d474699d4faf9121d1bf3906513af16 Mon Sep 17 00:00:00 2001
From: Keir Fraser <keir.xen@gmail.com>
Date: Thu, 19 Oct 2023 12:05:53 +0100
Subject: [PATCH] Kryoflux, SCP: Allow number of revolutions to be specified in
 output

eg gw convert a.ipf a.scp::revs=3
---
 src/greaseweazle/flux.py           | 30 ++++++++++++++++++++++++++++++
 src/greaseweazle/image/kryoflux.py | 21 ++++++++++++++++++++-
 src/greaseweazle/image/scp.py      | 19 ++++++++++++++++++-
 3 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/src/greaseweazle/flux.py b/src/greaseweazle/flux.py
index a581955b..1575fcd0 100644
--- a/src/greaseweazle/flux.py
+++ b/src/greaseweazle/flux.py
@@ -85,6 +85,36 @@ def cue_at_index(self) -> None:
         self.index_cued = True
 
 
+    def set_nr_revs(self, revs:int) -> None:
+
+        self.cue_at_index()
+        error.check(self.index_list,
+                    'Need at least one revolution to adjust # revolutions')
+
+        if len(self.index_list) > revs:
+            self.index_list = self.index_list[:revs]
+            to_index = sum(self.index_list)
+            for i in range(len(self.list)):
+                to_index -= self.list[i]
+                if to_index < 0:
+                    self.list = self.list[:i]
+                    break
+
+        while len(self.index_list) < revs:
+            nr = min(revs - len(self.index_list), len(self.index_list))
+            to_index = sum(self.index_list[:nr])
+            l = self.list
+            for i in range(len(l)):
+                to_index -= l[i]
+                if to_index < 0:
+                    to_index += l[i]
+                    l = l[:i]
+                    break
+            if self.list:
+                self.list = l + [to_index + self.list[0]] + self.list[1:]
+            self.index_list = self.index_list[:nr] + self.index_list
+
+
     def flux_for_writeout(self, cue_at_index) -> WriteoutFlux:
 
         # Splice at index unless we know better.
diff --git a/src/greaseweazle/image/kryoflux.py b/src/greaseweazle/image/kryoflux.py
index 2461fba9..cf9c2874 100644
--- a/src/greaseweazle/image/kryoflux.py
+++ b/src/greaseweazle/image/kryoflux.py
@@ -5,6 +5,8 @@
 # This is free and unencumbered software released into the public domain.
 # See the file COPYING for more details, or visit <http://unlicense.org>.
 
+from typing import Optional
+
 import struct, re, math, os, datetime
 import itertools as it
 
@@ -34,12 +36,14 @@ class OOB:
 class KFOpts(ImageOpts):
     """sck: Sample clock to use for flux timings.
     Suffix 'm' for MHz. For example: sck=72m
+    revs: Number of revolutions to output per track.
     """
 
-    w_settings = [ 'sck' ]
+    w_settings = [ 'sck', 'revs' ]
 
     def __init__(self) -> None:
         self._sck: float = def_sck
+        self._revs: Optional[int] = None
 
     @property
     def sck(self) -> float:
@@ -55,6 +59,18 @@ def sck(self, sck: str):
         except ValueError:
             raise error.Fatal("Kryoflux: Bad sck value: '%s'\n" % sck)
 
+    @property
+    def revs(self) -> Optional[int]:
+        return self._revs
+    @revs.setter
+    def revs(self, revs: str) -> None:
+        try:
+            self._revs = int(revs)
+            if self._revs < 1:
+                raise ValueError
+        except ValueError:
+            raise error.Fatal("Kryoflux: Invalid revs: '%s'" % revs)
+
 
 class KryoFlux(Image):
 
@@ -230,6 +246,9 @@ def emit(f):
         # So let's give it what it wants.
         flux.cue_at_index()
 
+        if self.opts.revs is not None:
+            flux.set_nr_revs(self.opts.revs)
+
         factor = sck / flux.sample_freq
         dat = bytearray()
 
diff --git a/src/greaseweazle/image/scp.py b/src/greaseweazle/image/scp.py
index b06ab98b..0d0ab454 100644
--- a/src/greaseweazle/image/scp.py
+++ b/src/greaseweazle/image/scp.py
@@ -71,13 +71,15 @@ class SCPHeaderFlags(IntFlag):
 class SCPOpts(ImageOpts):
     """legacy_ss: Set to True to generate (incorrect) legacy single-sided
     SCP image.
+    revs: Number of revolutions to output per track.
     """
 
-    w_settings = [ 'disktype', 'legacy_ss' ]
+    w_settings = [ 'disktype', 'legacy_ss', 'revs' ]
 
     def __init__(self) -> None:
         self.legacy_ss = False
         self._disktype = 0x80 # Other
+        self._revs: Optional[int] = None
 
     @property
     def disktype(self) -> int:
@@ -95,6 +97,18 @@ def disktype(self, disktype):
                 raise error.Fatal("Bad SCP disktype: '%s'\n" % disktype
                                   + 'Valid types:\n' + util.columnify(l))
 
+    @property
+    def revs(self) -> Optional[int]:
+        return self._revs
+    @revs.setter
+    def revs(self, revs: str) -> None:
+        try:
+            self._revs = int(revs)
+            if self._revs < 1:
+                raise ValueError
+        except ValueError:
+            raise error.Fatal("Kryoflux: Invalid revs: '%s'" % revs)
+
 
 class SCPTrack:
 
@@ -279,6 +293,9 @@ def emit_track(self, cyl: int, side: int, track) -> None:
         # what they want.
         flux.cue_at_index()
 
+        if self.opts.revs is not None:
+            flux.set_nr_revs(self.opts.revs)
+
         if not flux.index_cued:
             self.index_cued = False