From acbbb8354aabe6ec841e0472764935145295a9fe Mon Sep 17 00:00:00 2001
From: Jean Pierre Cimalando <jp-dev@inbox.ru>
Date: Sun, 3 May 2020 15:08:05 +0200
Subject: [PATCH] Add categorization of opcodes

---
 src/sfizz/Opcode.cpp | 31 +++++++++++++++++++++++++++++++
 src/sfizz/Opcode.h   | 19 +++++++++++++++++++
 tests/OpcodeT.cpp    | 10 ++++++++++
 3 files changed, 60 insertions(+)

diff --git a/src/sfizz/Opcode.cpp b/src/sfizz/Opcode.cpp
index fbe8bcc5..7451fa3d 100644
--- a/src/sfizz/Opcode.cpp
+++ b/src/sfizz/Opcode.cpp
@@ -6,11 +6,14 @@
 
 #include "Opcode.h"
 #include "StringViewHelpers.h"
+#include "absl/strings/ascii.h"
+#include "absl/strings/match.h"
 #include <cctype>
 
 sfz::Opcode::Opcode(absl::string_view inputOpcode, absl::string_view inputValue)
     : opcode(trim(inputOpcode))
     , value(trim(inputValue))
+    , category(identifyCategory(inputOpcode))
 {
     size_t nextCharIndex { 0 };
     int parameterPosition { 0 };
@@ -34,3 +37,31 @@ sfz::Opcode::Opcode(absl::string_view inputOpcode, absl::string_view inputValue)
     if (nextCharIndex != opcode.npos)
         lettersOnlyHash = hashNoAmpersand(opcode.substr(nextCharIndex), lettersOnlyHash);
 }
+
+static absl::string_view extractBackInteger(absl::string_view opcodeName)
+{
+    size_t n = opcodeName.size();
+    size_t i = n;
+    while (i > 0 && absl::ascii_isdigit(opcodeName[i - 1])) --i;
+    return opcodeName.substr(i);
+}
+
+sfz::OpcodeCategory sfz::Opcode::identifyCategory(absl::string_view name)
+{
+    sfz::OpcodeCategory category = kOpcodeNormal;
+
+    if (!name.empty() && absl::ascii_isdigit(name.back())) {
+        absl::string_view part = name;
+        part.remove_suffix(extractBackInteger(name).size());
+        if (absl::EndsWith(part, "_oncc") || absl::EndsWith(part, "_cc"))
+            category = kOpcodeOnCcN;
+        else if (absl::EndsWith(part, "_curvecc"))
+            category = kOpcodeCurveCcN;
+        else if (absl::EndsWith(part, "_stepcc"))
+            category = kOpcodeStepCcN;
+        else if (absl::EndsWith(part, "_smoothcc"))
+            category = kOpcodeSmoothCcN;
+    }
+
+    return category;
+}
diff --git a/src/sfizz/Opcode.h b/src/sfizz/Opcode.h
index 492cfb1e..25d2f931 100644
--- a/src/sfizz/Opcode.h
+++ b/src/sfizz/Opcode.h
@@ -20,6 +20,22 @@
 #include "absl/strings/numbers.h"
 
 namespace sfz {
+/**
+ * @brief A category which an opcode may belong to.
+ */
+enum OpcodeCategory {
+    //! An ordinary opcode
+    kOpcodeNormal,
+    //! A region opcode which matches *_onccN or *_ccN
+    kOpcodeOnCcN,
+    //! A region opcode which matches *_curveccN
+    kOpcodeCurveCcN,
+    //! A region opcode which matches *_stepccN
+    kOpcodeStepCcN,
+    //! A region opcode which matches *_smoothccN
+    kOpcodeSmoothCcN,
+};
+
 /**
  * @brief Opcode description class. The class parses the parameters
  * of the opcode on construction.
@@ -33,6 +49,9 @@ struct Opcode {
     uint64_t lettersOnlyHash { Fnv1aBasis };
     // This is to handle the integer parameters of some opcodes
     std::vector<uint16_t> parameters;
+    OpcodeCategory category;
+private:
+    static OpcodeCategory identifyCategory(absl::string_view name);
     LEAK_DETECTOR(Opcode);
 };
 
diff --git a/tests/OpcodeT.cpp b/tests/OpcodeT.cpp
index ffbb07ab..6a0123cf 100644
--- a/tests/OpcodeT.cpp
+++ b/tests/OpcodeT.cpp
@@ -138,3 +138,13 @@ TEST_CASE("[Opcode] Note values")
     REQUIRE(noteValue);
     REQUIRE(*noteValue == 61);
 }
+
+TEST_CASE("[Opcode] Categories")
+{
+    REQUIRE(sfz::Opcode("sample", "").category == sfz::kOpcodeNormal);
+    REQUIRE(sfz::Opcode("amplitude_oncc11", "").category == sfz::kOpcodeOnCcN);
+    REQUIRE(sfz::Opcode("cutoff_cc22", "").category == sfz::kOpcodeOnCcN);
+    REQUIRE(sfz::Opcode("lfo01_pitch_curvecc33", "").category == sfz::kOpcodeCurveCcN);
+    REQUIRE(sfz::Opcode("pan_stepcc44", "").category == sfz::kOpcodeStepCcN);
+    REQUIRE(sfz::Opcode("noise_level_smoothcc55", "").category == sfz::kOpcodeSmoothCcN);
+}