From 8040d6755f2a32fac85227865c2787147ebf941d Mon Sep 17 00:00:00 2001
From: Miloslav Ciz <drummyfish@disroot.org>
Date: Wed, 15 Jan 2025 23:08:31 +0100
Subject: [PATCH] Add replay loading

---
 game.h    | 14 +++++------
 general.h | 11 +++++++++
 racing.h  | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 85 insertions(+), 13 deletions(-)

diff --git a/game.h b/game.h
index 20b2fc7..2cc9661 100644
--- a/game.h
+++ b/game.h
@@ -666,6 +666,11 @@ void LCR_gameDraw3DView(void)
   }
 }
 
+void _LCR_gameResourceCharWrite(char c)
+{ // TODO
+  printf("%c",c);
+}
+
 /**
   Helper subroutine, handles user input during main loop frame, EXCEPT for the
   driving input (that is handled in the loop itself).
@@ -791,8 +796,8 @@ void LCR_gameHandleInput(void)
 
     case LCR_GAME_STATE_RUN_FINISHED:
       if (LCR_game.keyStates[LCR_KEY_A] == 1)
-        //LCR_gameResetRun(LCR_racing.playingReplay);
-        LCR_gameResetRun(1);
+//        LCR_gameResetRun(LCR_racing.playingReplay);
+   LCR_gameResetRun(1);
 
       break;
 
@@ -858,11 +863,6 @@ void LCR_gameHandleInput(void)
       LCR_game.menu.selectedTab == 1 ? 'M' : 'R');
 }
 
-void _LCR_gameResourceCharWrite(char c)
-{
-  printf("%c",c);
-}
-
 uint8_t LCR_gameStep(uint32_t time)
 {
   uint32_t sleep = 0;
diff --git a/general.h b/general.h
index 8cce340..cf3987e 100644
--- a/general.h
+++ b/general.h
@@ -53,4 +53,15 @@ char _LCR_hexDigit(int i)
   return i < 10 ? '0' + i : ('a' - 10 + i);
 }
 
+int _LCR_hexDigitVal(char c)
+{
+  if (c >= '0' && c <= '9')
+    return c - '0';
+
+  if (c >= 'a' && c <= 'f')
+    return c - 'a' + 10;
+
+  return -1;
+}
+
 #endif // guard
diff --git a/racing.h b/racing.h
index 549d243..8f0b85f 100644
--- a/racing.h
+++ b/racing.h
@@ -16,11 +16,12 @@
   - Replay text format: first there is the name of the map terminated by ';',
     then hexadecimal hash of the map follows (exactly 8 characters), then
     blank character follows, then achieved time as a series of decimal digits
-    expressing the number of milliseconds, then a non-decimal character follows,
-    then the replay data, i.e. the series of 16 bit words in hexadecimal. The
-    blocks (but nothing else) may be preceeded or followed by blank characters.
-    All hexadecimal letters must be lowercase. The word 00000000 may optinally
-    be used to terminate the replay, the rest of the string will be ignored.
+    expressing the number of milliseconds, then the replay data, i.e. the series
+    of 16 bit words in hexadecimal, each preceded by ':'. The events (but
+    nothing else) may otherwise be preceeded or followed by other characters
+    (possible comments). All hexadecimal letters must be lowercase. The word
+    00000000 may optinally be used to terminate the replay, the rest of the
+    string will be ignored.
 */
 
 typedef int32_t LCR_GameUnit;  ///< abstract game unit
@@ -189,7 +190,7 @@ void LCR_replayOutputStr(void (*printChar)(char))
   for (int i = 0; i < LCR_replay.eventCount; ++i)
   {
     uint16_t e = LCR_replay.events[i];
-    printChar(' ');
+    printChar(':');
 
     for (int j = 0; j < 4; ++j)
     {
@@ -201,6 +202,66 @@ void LCR_replayOutputStr(void (*printChar)(char))
   printChar('\n');
 }
 
+/**
+  Reads replay from string using provided function that returns next character
+  in the string. Returns 1 on success, else 0.
+*/
+int LCR_replayLoadFromStr(char (*nextChar)(void))
+{
+  char c = ' ';
+
+  LCR_replay.eventCount = 0;
+  LCR_replay.achievedTime = 0;
+
+  do // map name
+  {
+    c = nextChar();
+
+    if (c == 0)
+      return 0;
+  } while (c != ';');
+
+  for (int i = 0; i < 8; ++i) // hash
+    if (_LCR_hexDigitVal(nextChar()) < 0)
+      return 0;
+
+  nextChar();
+
+  while (1) // time
+  {
+    c = nextChar();
+
+    if (c < '0' || c > '9')
+      break;
+
+    LCR_replay.achievedTime = LCR_replay.achievedTime * 10 + c - '0';
+  }
+
+  while (c != 0) // events
+  {
+    if (c == ':')
+    {
+      uint16_t e = 0;
+
+      for (int i = 0; i < 4; ++i)
+        e = (e << 4) | _LCR_hexDigitVal(nextChar());
+
+      if (e == 0)
+        break;
+      
+      if (LCR_replay.eventCount >= LCR_SETTING_REPLAY_MAX_SIZE)
+        return 0;
+
+      LCR_replay.events[LCR_replay.eventCount] = e;
+      LCR_replay.eventCount++;
+    }
+
+    c = nextChar();
+  }
+
+  return 1;
+}
+
 /**
   During playing of a replay returns the next input and shifts to next frame.
 */