From 3697471d7f5b4316cffe758eb675f795cbca9ae5 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Fri, 1 May 2026 18:22:21 +0530
Subject: [PATCH 01/14] Added clang format

---
 .../CppLib/src/AlternatingCaseConversion.cpp  |  13 +--
 .../CppLib/src/CapitalizeWordsConversion.cpp  |   6 +-
 .../CppLib/src/ConversionResult.cpp           |  75 +++++++------
 .../CppLib/src/InvertWordsConversion.cpp      |   3 +-
 .../CppLib/src/ProcessStringDLL.cpp           | 102 +++++++++---------
 .../CppLib/src/RemoveSpacesConversion.cpp     |   3 +-
 .../CppLib/src/RemoveVowelsConversion.cpp     |   3 +-
 .../CppLib/src/SentenceCaseConversion.cpp     |   3 +-
 8 files changed, 105 insertions(+), 103 deletions(-)

diff --git a/backend/CaseConversionAPI/CppLib/src/AlternatingCaseConversion.cpp b/backend/CaseConversionAPI/CppLib/src/AlternatingCaseConversion.cpp
index e9229b7..4ddb38f 100644
--- a/backend/CaseConversionAPI/CppLib/src/AlternatingCaseConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/AlternatingCaseConversion.cpp
@@ -26,11 +26,12 @@
 /*********************************************************************/
 
 #include "AlternatingCaseConversion.hpp"
+#include "ConversionResult.hpp"
 #include "LowerCaseConversion.hpp"
 #include "UpperCaseConversion.hpp"
-#include "ConversionResult.hpp"
 
-ConversionResult AlternatingCaseConversion::convert(const std::string &input) const {
+ConversionResult
+AlternatingCaseConversion::convert(const std::string &input) const {
   LowerCaseConversion lowerConv;
   UpperCaseConversion upperConv;
 
@@ -44,17 +45,17 @@ ConversionResult AlternatingCaseConversion::convert(const std::string &input) co
 
       if (upper) {
         auto resObj = upperConv.convert(temp);
-        finalResult += resObj.get_c_str(); 
+        finalResult += resObj.get_c_str();
       } else {
         auto resObj = lowerConv.convert(temp);
-        finalResult += resObj.get_c_str(); 
+        finalResult += resObj.get_c_str();
       }
 
       upper = !upper;
     } else {
-      finalResult += c; 
+      finalResult += c;
       if (c == ' ') {
-        upper = true; 
+        upper = true;
       }
     }
   }
diff --git a/backend/CaseConversionAPI/CppLib/src/CapitalizeWordsConversion.cpp b/backend/CaseConversionAPI/CppLib/src/CapitalizeWordsConversion.cpp
index 36893bb..3075e3a 100644
--- a/backend/CaseConversionAPI/CppLib/src/CapitalizeWordsConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/CapitalizeWordsConversion.cpp
@@ -30,7 +30,8 @@
 #include "UpperCaseConversion.hpp"
 #include <sstream>
 
-ConversionResult CapitalizeWordsConversion::convert(const std::string &input) const {
+ConversionResult
+CapitalizeWordsConversion::convert(const std::string &input) const {
   LowerCaseConversion lowerConv;
   UpperCaseConversion upperConv;
 
@@ -44,7 +45,8 @@ ConversionResult CapitalizeWordsConversion::convert(const std::string &input) co
     }
 
     // Convert whole word to lowercase first
-    word = ConversionResult(lowerConv.convert(word)).get_c_str(); // Get C-string from ConversionResult
+    word = ConversionResult(lowerConv.convert(word))
+               .get_c_str(); // Get C-string from ConversionResult
 
     // Capitalize first letter using UpperCaseConversion
     std::string firstChar(1, word[0]);
diff --git a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
index d6c31d6..bdfb96a 100644
--- a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
@@ -34,80 +34,77 @@
 /* Constructor                                                       */
 /*********************************************************************/
 
-ConversionResult::ConversionResult(const char* input) {
-    if (input) {
-        data = new char[std::strlen(input) + 1];
-        std::strcpy(data, input);
-    } else {
-        data = nullptr;
-    }
+ConversionResult::ConversionResult(const char *input) {
+  if (input) {
+    data = new char[std::strlen(input) + 1];
+    std::strcpy(data, input);
+  } else {
+    data = nullptr;
+  }
 }
 
 /*********************************************************************/
 /* Destructor                                                        */
 /*********************************************************************/
 
-ConversionResult::~ConversionResult() {
-    delete[] data;
-}
+ConversionResult::~ConversionResult() { delete[] data; }
 
 /*********************************************************************/
 /* Copy Constructor                                                  */
 /*********************************************************************/
 
-ConversionResult::ConversionResult(const ConversionResult& other) {
-    if (other.data) {
-        data = new char[std::strlen(other.data) + 1];
-        std::strcpy(data, other.data);
-    } else {
-        data = nullptr;
-    }
+ConversionResult::ConversionResult(const ConversionResult &other) {
+  if (other.data) {
+    data = new char[std::strlen(other.data) + 1];
+    std::strcpy(data, other.data);
+  } else {
+    data = nullptr;
+  }
 }
 
 /*********************************************************************/
 /* Copy Assignment                                                   */
 /*********************************************************************/
 
-ConversionResult& ConversionResult::operator=(const ConversionResult& other) {
-    if (this != &other) {
-        delete[] data;
+ConversionResult &ConversionResult::operator=(const ConversionResult &other) {
+  if (this != &other) {
+    delete[] data;
 
-        if (other.data) {
-            data = new char[std::strlen(other.data) + 1];
-            std::strcpy(data, other.data);
-        } else {
-            data = nullptr;
-        }
+    if (other.data) {
+      data = new char[std::strlen(other.data) + 1];
+      std::strcpy(data, other.data);
+    } else {
+      data = nullptr;
     }
-    return *this;
+  }
+  return *this;
 }
 
 /*********************************************************************/
 /* Move Constructor                                                  */
 /*********************************************************************/
 
-ConversionResult::ConversionResult(ConversionResult&& other) noexcept
+ConversionResult::ConversionResult(ConversionResult &&other) noexcept
     : data(other.data) {
-    other.data = nullptr;
+  other.data = nullptr;
 }
 
 /*********************************************************************/
 /* Move Assignment                                                   */
 /*********************************************************************/
 
-ConversionResult& ConversionResult::operator=(ConversionResult&& other) noexcept {
-    if (this != &other) {
-        delete[] data;
-        data = other.data;
-        other.data = nullptr;
-    }
-    return *this;
+ConversionResult &
+ConversionResult::operator=(ConversionResult &&other) noexcept {
+  if (this != &other) {
+    delete[] data;
+    data = other.data;
+    other.data = nullptr;
+  }
+  return *this;
 }
 
 /*********************************************************************/
 /* Accessor                                                          */
 /*********************************************************************/
 
-const char* ConversionResult::get_c_str() const {
-    return data;
-}
\ No newline at end of file
+const char *ConversionResult::get_c_str() const { return data; }
\ No newline at end of file
diff --git a/backend/CaseConversionAPI/CppLib/src/InvertWordsConversion.cpp b/backend/CaseConversionAPI/CppLib/src/InvertWordsConversion.cpp
index dcfb5bc..26eb875 100644
--- a/backend/CaseConversionAPI/CppLib/src/InvertWordsConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/InvertWordsConversion.cpp
@@ -27,7 +27,8 @@
 #include <algorithm>
 #include <sstream>
 
-ConversionResult InvertWordsConversion::convert(const std::string &input) const {
+ConversionResult
+InvertWordsConversion::convert(const std::string &input) const {
   std::istringstream iss(input);
   std::ostringstream oss;
   std::string word;
diff --git a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
index dc6745e..b91591b 100644
--- a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
@@ -130,61 +130,59 @@ static bool mapConversionType(ConversionChoice choice, ConversionType &type) {
 
 extern "C" {
 
-API const char *processStringDLL(const char *input, int choiceInt, const char *traceId) {
-    try {
-        if (!input) return safeError("ERROR_NULL_INPUT");
-
-        size_t inputLength = std::strlen(input);
-        if (inputLength > MAX_INPUT_SIZE) {
-            return safeError("ERROR_BUFFER_OVERFLOW_LIMIT_5MB");
-        }
-
-        if (choiceInt < 0) {
-            return safeError("ERROR_NEGATIVE_CONVERSION_CHOICE");
-        }
-
-        ConversionChoice choice = static_cast<ConversionChoice>(choiceInt);
-        ConversionType type;
-
-        if (!mapConversionType(choice, type)) {
-            return safeError("ERROR_INVALID_CONVERSION_CHOICE");
-        }
-
-        Client client;
-        if (traceId) {
-            client.setTraceId(traceId);
-        }
-
-        // 1. Create the engine and execute
-        client.setStrategy(StringConversionFactory::create(type));
-        
-        // 2. Capture the result in a local scope to ensure its lifetime
-        ConversionResult result = client.execute(std::string(input));
-        const char* rawPtr = result.get_c_str();
-
-        if (!rawPtr) 
-          return safeError("ERROR_ENGINE_RETURNED_NULL");
-
-        // 3. Perform a DEEP COPY immediately into malloc'd memory
-        size_t resLen = std::strlen(rawPtr);
-        char *output = static_cast<char *>(std::malloc(resLen + 1));
-        
-        if (!output) 
-          return safeError("FATAL_ALLOCATION_FAILURE");
-
-        std::memcpy(output, rawPtr, resLen + 1);
-
-        // 4. The 'result' object will be destroyed after this return, 
-        // but 'output' is now independent on the heap.
-        return output;
-
-    } catch (...) {
-        return safeError("ERROR_INTERNAL_EXCEPTION");
+API const char *processStringDLL(const char *input, int choiceInt,
+                                 const char *traceId) {
+  try {
+    if (!input)
+      return safeError("ERROR_NULL_INPUT");
+
+    size_t inputLength = std::strlen(input);
+    if (inputLength > MAX_INPUT_SIZE) {
+      return safeError("ERROR_BUFFER_OVERFLOW_LIMIT_5MB");
     }
+
+    if (choiceInt < 0) {
+      return safeError("ERROR_NEGATIVE_CONVERSION_CHOICE");
+    }
+
+    ConversionChoice choice = static_cast<ConversionChoice>(choiceInt);
+    ConversionType type;
+
+    if (!mapConversionType(choice, type)) {
+      return safeError("ERROR_INVALID_CONVERSION_CHOICE");
+    }
+
+    Client client;
+    if (traceId) {
+      client.setTraceId(traceId);
+    }
+
+    client.setStrategy(StringConversionFactory::create(type));
+
+    ConversionResult result = client.execute(std::string(input));
+    const char *rawPtr = result.get_c_str();
+
+    if (!rawPtr)
+      return safeError("ERROR_ENGINE_RETURNED_NULL");
+
+    size_t resLen = std::strlen(rawPtr);
+    char *output = static_cast<char *>(std::malloc(resLen + 1));
+
+    if (!output)
+      return safeError("FATAL_ALLOCATION_FAILURE");
+
+    std::memcpy(output, rawPtr, resLen + 1);
+
+    return output;
+
+  } catch (...) {
+    return safeError("ERROR_INTERNAL_EXCEPTION");
+  }
 }
 
-API void freeString(char *str) { 
-    if (str) std::free(str); 
+API void freeString(char *str) {
+  if (str)
+    std::free(str);
 }
 
 } // extern "C"
\ No newline at end of file
diff --git a/backend/CaseConversionAPI/CppLib/src/RemoveSpacesConversion.cpp b/backend/CaseConversionAPI/CppLib/src/RemoveSpacesConversion.cpp
index 46e0ae6..7d15c14 100644
--- a/backend/CaseConversionAPI/CppLib/src/RemoveSpacesConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/RemoveSpacesConversion.cpp
@@ -26,7 +26,8 @@
 #include "RemoveSpacesConversion.hpp"
 #include <algorithm>
 
-ConversionResult RemoveSpacesConversion::convert(const std::string &input) const {
+ConversionResult
+RemoveSpacesConversion::convert(const std::string &input) const {
   std::string result = input;
   result.erase(std::remove(result.begin(), result.end(), ' '), result.end());
   return ConversionResult(result.c_str());
diff --git a/backend/CaseConversionAPI/CppLib/src/RemoveVowelsConversion.cpp b/backend/CaseConversionAPI/CppLib/src/RemoveVowelsConversion.cpp
index 20db859..86a3170 100644
--- a/backend/CaseConversionAPI/CppLib/src/RemoveVowelsConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/RemoveVowelsConversion.cpp
@@ -26,7 +26,8 @@
 #include "RemoveVowelsConversion.hpp"
 #include "LowerCaseConversion.hpp"
 
-ConversionResult RemoveVowelsConversion::convert(const std::string &input) const {
+ConversionResult
+RemoveVowelsConversion::convert(const std::string &input) const {
   LowerCaseConversion lowerConv;
   std::string lower = ConversionResult(lowerConv.convert(input)).get_c_str();
   std::string result;
diff --git a/backend/CaseConversionAPI/CppLib/src/SentenceCaseConversion.cpp b/backend/CaseConversionAPI/CppLib/src/SentenceCaseConversion.cpp
index 7877fb7..b26cdda 100644
--- a/backend/CaseConversionAPI/CppLib/src/SentenceCaseConversion.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/SentenceCaseConversion.cpp
@@ -29,7 +29,8 @@
 #include "LowerCaseConversion.hpp"
 #include "UpperCaseConversion.hpp"
 
-ConversionResult SentenceCaseConversion::convert(const std::string &input) const {
+ConversionResult
+SentenceCaseConversion::convert(const std::string &input) const {
   if (input.empty()) {
     return ConversionResult(input.c_str());
   }

From cdc482fb096853ee8eaa83759e61560f133b4797 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Fri, 1 May 2026 18:44:26 +0530
Subject: [PATCH 02/14] refactor: replace insecure strcpy with memcpy in
 ConversionResult

Optimized RAII ownership model for M2 architecture and resolved clang-analyzer security violations (CWE-119).
---
 .../CppLib/src/ConversionResult.cpp           | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
index bdfb96a..9bd6623 100644
--- a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
@@ -37,7 +37,8 @@
 ConversionResult::ConversionResult(const char *input) {
   if (input) {
     data = new char[std::strlen(input) + 1];
-    std::strcpy(data, input);
+    size_t length = std::strlen(input);
+    std::memcpy(data, input, length + 1);
   } else {
     data = nullptr;
   }
@@ -55,8 +56,9 @@ ConversionResult::~ConversionResult() { delete[] data; }
 
 ConversionResult::ConversionResult(const ConversionResult &other) {
   if (other.data) {
-    data = new char[std::strlen(other.data) + 1];
-    std::strcpy(data, other.data);
+    size_t length = std::strlen(other.data);
+    data = new char[length + 1];
+    std::memcpy(data, other.data, length + 1);
   } else {
     data = nullptr;
   }
@@ -68,14 +70,16 @@ ConversionResult::ConversionResult(const ConversionResult &other) {
 
 ConversionResult &ConversionResult::operator=(const ConversionResult &other) {
   if (this != &other) {
-    delete[] data;
-
+    char* new_data = nullptr;
     if (other.data) {
-      data = new char[std::strlen(other.data) + 1];
-      std::strcpy(data, other.data);
-    } else {
-      data = nullptr;
+      size_t length = std::strlen(other.data);
+      new_data = new char[length + 1];
+      std::memcpy(new_data, other.data, length + 1);
     }
+    
+    // Clean up old data and assign new
+    delete[] data;
+    data = new_data;
   }
   return *this;
 }

From bef2df6ec4df833dd7eff2369fdb94268c2b5c20 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Fri, 1 May 2026 18:48:32 +0530
Subject: [PATCH 03/14] refactor: replace insecure strcpy with memcpy in
 ConversionResult

Optimized RAII ownership model for M2 architecture and resolved clang-analyzer security violations (CWE-119).
---
 backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
index 9bd6623..919182a 100644
--- a/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ConversionResult.cpp
@@ -70,13 +70,13 @@ ConversionResult::ConversionResult(const ConversionResult &other) {
 
 ConversionResult &ConversionResult::operator=(const ConversionResult &other) {
   if (this != &other) {
-    char* new_data = nullptr;
+    char *new_data = nullptr;
     if (other.data) {
       size_t length = std::strlen(other.data);
       new_data = new char[length + 1];
       std::memcpy(new_data, other.data, length + 1);
     }
-    
+
     // Clean up old data and assign new
     delete[] data;
     data = new_data;

From 53f45e0f416a38e9b2eaef13fa835459f78a4277 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Sun, 3 May 2026 03:06:20 +0530
Subject: [PATCH 04/14] All three OS build

---
 .../CaseConversionAPI/CppLib/CMakeLists.txt   |   4 +-
 .../CppLib/Scripts/orchestrate-native.md      | 106 ++++++++++++++++++
 .../CppLib/Scripts/orchestrate-native.sh      |  98 ++++++++++++----
 3 files changed, 187 insertions(+), 21 deletions(-)
 create mode 100644 backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.md

diff --git a/backend/CaseConversionAPI/CppLib/CMakeLists.txt b/backend/CaseConversionAPI/CppLib/CMakeLists.txt
index e1bfd28..b51cd8e 100644
--- a/backend/CaseConversionAPI/CppLib/CMakeLists.txt
+++ b/backend/CaseConversionAPI/CppLib/CMakeLists.txt
@@ -1,6 +1,8 @@
 cmake_minimum_required(VERSION 3.14)
 
-cmake_policy(SET CMP0135 NEW)
+if(POLICY CMP0135)
+  cmake_policy(SET CMP0135 NEW)
+endif()
 
 # Add this near the top, after project()
 if(CMAKE_BUILD_TYPE STREQUAL "Debug" OR NOT CMAKE_BUILD_TYPE)
diff --git a/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.md b/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.md
new file mode 100644
index 0000000..f9ae92b
--- /dev/null
+++ b/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.md
@@ -0,0 +1,106 @@
+# C++ Core Orchestration Guide (Monorepo)
+
+This guide provides the end-to-end instructions for building, optimizing, and testing the high-performance C++ engine across different environments using the orchestrate-native.sh script.
+
+## 1. macOS (Local / Native)
+
+Targeting Apple M2 Silicon for maximum performance.
+
+### Setup
+
+1. Install Tooling: Ensure you have CMake and the Apple Command Line Tools.
+
+```Bash
+brew install cmake
+xcode-select --install
+```
+
+2. Permissions: Make the script executable.
+
+```Bash
+chmod +x backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh
+```
+
+Run
+
+Run directly from the project root:
+
+```Bash
+./backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh macos-latest
+```
+
+### The Fix: Purge the Cache
+
+You must delete the existing build artifacts before switching environments. Run this in your Mac terminal:
+
+```Bash
+# 1. Clear the corrupted cache
+rm -rf backend/CaseConversionAPI/CppLib/build/*
+
+# 2. Run the script again
+./backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh macos-latest
+```
+
+## 2. Linux (Docker)
+
+Targeting a clean Ubuntu environment for cloud-native validation.
+
+Setup (Initial Login)
+
+Build the Environment:
+
+```Bash
+docker build -t cpp-linux-env -f - <<EOF .
+FROM ubuntu:22.04
+RUN apt-get update && apt-get install -y build-essential cmake git
+WORKDIR /app
+EOF
+```
+
+### Mount & Enter (Login)
+
+```Bash
+docker rm -f cpp-dev
+docker run -it --rm --name cpp-dev -v "$(pwd)":/app cpp-linux-env /bin/bash
+```
+
+### Run
+
+Inside the Docker shell:
+
+```Bash
+./backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh ubuntu-latest
+```
+
+## 3. Windows (Docker Cross-Build)
+
+Targeting Windows verification from your Mac using MinGW or MSVC.
+
+Setup
+
+To compile Windows binaries without leaving your Mac, use a specialized Docker container:
+
+Create Windows-Toolchain Image:
+
+Clear the Windows artifacts:
+
+```Bash
+rm -rf backend/CaseConversionAPI/CppLib/build/*
+```
+
+```Bash
+docker build -t cpp-win-env -f - . <<EOF
+FROM ubuntu:22.04
+RUN apt-get update && apt-get install -y build-essential cmake mingw-w64 make
+WORKDIR /app
+EOF
+```
+
+Run
+
+Run as a "one-shot" command from the project root:
+
+```Bash
+docker run --rm -v "$(pwd)":/app cpp-win-env \
+/bin/bash ./backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh windows-latest
+```
diff --git a/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh b/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh
index eef316b..d603b41 100755
--- a/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh
+++ b/backend/CaseConversionAPI/CppLib/Scripts/orchestrate-native.sh
@@ -1,9 +1,9 @@
 #!/bin/bash
 #*********************************************************************/
-#  Utility Script - C++ Core Orchestration (Monorepo)                */
+#  Utility Script - C++ Core Orchestration (Monorepo)                 */
 #                                                                    */
-# Purpose   : Configures, builds, and executes C++ logic & tests.    */
-# Location  : backend/CaseConversionAPI/CppLib/Scripts/run.sh        */
+# Purpose   : Configures, builds, and executes C++ logic & tests.     */
+# Location  : backend/CaseConversionAPI/CppLib/Scripts/run.sh         */
 #                                                                    */
 # Revision History:                                                  */
 # ------------------------------------------------------------------ */
@@ -12,44 +12,102 @@
 # 1.0        2026-04-14  Nitish Singh    Initial C++ Run Script      */
 # 1.1        2026-04-15  Nitish Singh    Updated for /backend path   */
 # 1.2        2026-04-16  Nitish Singh    Added Dynamic Path Sync     */
+# 1.3        2026-05-02  Nitish Singh    Added Matrix OS Support     */
 #*********************************************************************/
 
-set -e
+set -euo pipefail
 
 # -------------------------------
-# 1. Path Synchronization
+# 1. Argument Handling (Matrix OS)
 # -------------------------------
-# Get the absolute path to this script's folder
-SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
+if [ "$#" -ne 1 ]; then
+  echo "Usage: $0 <matrix-os>"
+  echo "Example: $0 macos-latest | ubuntu-latest | windows-latest"
+  exit 1
+fi
+
+OS_TARGET=$(echo "$1" | tr '[:upper:]' '[:lower:]')
+echo "Targeting Matrix OS: $OS_TARGET"
 
-# Target the CppLib root (one level up from Scripts/)
+# -------------------------------
+# 2. Path Synchronization
+# -------------------------------
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
 CPP_ROOT="$SCRIPT_DIR/.."
 cd "$CPP_ROOT"
 
 # -------------------------------
-# 2. Compilation Layer
+# 3. OS-Specific Configuration
+# -------------------------------
+# Initialize CMAKE_ARGS as an array to handle spaces safely
+CMAKE_ARGS=("-DCMAKE_BUILD_TYPE=Release")
+
+if [[ "$OS_TARGET" == *"macos"* ]]; then
+  echo "Setting up Apple Silicon / macOS optimization..."
+  CMAKE_ARGS+=("-DARCH_ARM64=ON" "-DUSE_PCORES=ON")
+  
+elif [[ "$OS_TARGET" == *"ubuntu"* || "$OS_TARGET" == *"linux"* ]]; then
+  echo "Setting up Linux / GCC optimization..."
+  CMAKE_ARGS+=("-DCMAKE_CXX_FLAGS=-O3 -march=native" "-G" "Unix Makefiles")
+
+elif [[ "$OS_TARGET" == *"windows"* ]]; then
+  # Check if we are inside the Docker container (where MinGW lives)
+  if command -v x86_64-w64-mingw32-gcc &> /dev/null; then
+    echo "Setting up MinGW / Windows cross-compilation..."
+    CMAKE_ARGS+=("-G" "Unix Makefiles")
+    CMAKE_ARGS+=("-DCMAKE_SYSTEM_NAME=Windows")
+    CMAKE_ARGS+=("-DCMAKE_C_COMPILER=x86_64-w64-mingw32-gcc")
+    CMAKE_ARGS+=("-DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-g++")
+  else
+    echo "Setting up MSVC / Windows optimization..."
+    CMAKE_ARGS+=("-G" "Visual Studio 17 2022" "-A" "x64")
+  fi  
+
+else
+  echo "Warning: Unrecognized OS target. Using generic build flags."
+fi 
+# -------------------------------
+# 4. Compilation Layer
 # -------------------------------
-echo "===== Configuring & Building C++ Core ====="
+echo "===== Configuring & Building C++ Core ($OS_TARGET) ====="
 
-# Create build directory relative to CppLib root
 mkdir -p build
 cd build
 
-# Configure and Build
-cmake .. -DCMAKE_BUILD_TYPE=Release
-cmake --build . --config Release --parallel
+# Use the array expansion syntax to preserve argument boundaries
+cmake .. "${CMAKE_ARGS[@]}"
+
+# Detect available cores for max performance
+NUM_CORES=$(nproc 2>/dev/null || sysctl -n hw.ncpu || echo 1)
+echo "Utilizing $NUM_CORES cores for parallel build..."
+
+cmake --build . --config Release --parallel "$NUM_CORES"
 
 # -------------------------------
-# 3. Execution Layer
+# 5. Execution Layer
 # -------------------------------
-echo -e "\n===== Running Core Tests ====="
-# This is the primary validation for your C++ logic
-./runTests
+# Skip execution if we are cross-compiling Windows binaries on a Linux host
+if [[ "$OS_TARGET" == *"windows"* ]] && [[ "$(uname)" == "Linux" ]]; then
+    echo -e "\n[Notice] Windows binary built successfully. Skipping execution on Linux host."
+else
+    echo -e "\n===== Running Core Tests ====="
+    
+    if [ -f "./runTests" ]; then
+        ./runTests
+    elif [ -f "./runTests.exe" ]; then
+        ./runTests.exe
+    elif [ -f "./Release/runTests.exe" ]; then
+        ./Release/runTests.exe
+    else
+        echo "Error: Test binary not found. Checking directory: $(pwd)"
+        ls -R
+        exit 1
+    fi
+fi
 
 # -------------------------------
-# 4. Workspace Restoration
+# 6. Workspace Restoration
 # -------------------------------
-# Return to the monorepo root
 cd ../../../..
 
 echo -e "\n===== Completed. Back in project root: $(pwd) ====="
\ No newline at end of file

From 31299e8202fee3f18e0843830afa42b6a44bcfb7 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Sun, 3 May 2026 04:22:03 +0530
Subject: [PATCH 05/14] style: fix clang-format violations in ProcessStringDLL

---
 backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
index b91591b..d728a3d 100644
--- a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
@@ -181,8 +181,9 @@ API const char *processStringDLL(const char *input, int choiceInt,
 }
 
 API void freeString(char *str) {
-  if (str)
+  if (str) {
     std::free(str);
+  }
 }
 
 } // extern "C"
\ No newline at end of file

From 5f1ca0d32cfa007c646d982e65d11d1dbd9a702f Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Sun, 3 May 2026 22:16:48 +0530
Subject: [PATCH 06/14] ci: add automated GitHub Actions cache cleanup workflow

---
 .github/workflows/cleanup-cache.yml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index 3047fc3..91be4aa 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -25,6 +25,10 @@ on:
     - cron: '0 0 * * *' # Daily at midnight UTC
   workflow_dispatch: {}
 
+permissions:
+  actions: write    # Required to delete caches
+  contents: read   # Required to read repository metadata
+
 jobs:
   cleanup:
     runs-on: ubuntu-latest

From 3a8ebd707e1dcff58041b14c8749c441891f423b Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Sun, 3 May 2026 22:35:01 +0530
Subject: [PATCH 07/14] ci: add automated GitHub Actions cache cleanup workflow

---
 .github/workflows/cleanup-cache.yml | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index 91be4aa..9717b08 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -25,45 +25,46 @@ on:
     - cron: '0 0 * * *' # Daily at midnight UTC
   workflow_dispatch: {}
 
+# Global permissions to fix "Exit Code 4" and CodeQL alerts
 permissions:
-  actions: write    # Required to delete caches
-  contents: read   # Required to read repository metadata
+  actions: write    # Crucial: Allows the 'gh' CLI to delete caches
+  contents: read   # Standard: Allows reading repo metadata
 
 jobs:
   cleanup:
     runs-on: ubuntu-latest
 
     steps:
-      # ------------------------------------------------------------
-      # Install GitHub CLI Cache Extension
-      # ------------------------------------------------------------
       - name: Install Cache Extension
         run: |
           gh extension install actions/gh-actions-cache
 
-      # ------------------------------------------------------------
-      # Cleanup Stale Caches (>7 days old)
-      # ------------------------------------------------------------
       - name: Delete Old Caches
         env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GH_TOKEN: ${{ secrets.SECRET_GITHUB_TOKEN }}
         run: |
           REPO=${{ github.repository }}
 
-          echo "Fetching cache list..."
+          echo "Fetching cache list for $REPO..."
+          # Fetch the list of caches
           gh actions-cache list -R $REPO --limit 1000 > caches.txt
 
           while read -r line; do
+            # Extract Cache Key and Last Used Timestamp
             KEY=$(echo $line | awk '{print $1}')
             LAST_USED=$(echo $line | awk '{print $3" "$4}')
 
+            # Convert to Timestamps
             LAST_USED_TS=$(date -d "$LAST_USED" +%s || echo 0)
             NOW_TS=$(date +%s)
 
+            # Calculate Age in Days
             AGE=$(( (NOW_TS - LAST_USED_TS) / 86400 ))
 
             if [ "$AGE" -gt 7 ]; then
-              echo "Deleting cache: $KEY (Age: $AGE days)"
+              echo "Deleting stale cache: $KEY (Age: $AGE days)"
               gh actions-cache delete "$KEY" -R $REPO --confirm
+            else
+              echo "Skipping active cache: $KEY (Age: $AGE days)"
             fi
           done < caches.txt
\ No newline at end of file

From 3105952773e70eb7be5763c15aca4494217ddf79 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 01:00:15 +0530
Subject: [PATCH 08/14] Resolves CodeQL missing-workflow-permissions alert by
 defining an explicit permissions block. This fixes the authorization failure
 (exit code 4) encountered when the GitHub CLI attempts to prune stale
 artifacts.

---
 .github/workflows/cleanup-cache.yml |  5 ++-
 ITERATIONS/README.md                | 49 +++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index 9717b08..a67fe61 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -25,10 +25,9 @@ on:
     - cron: '0 0 * * *' # Daily at midnight UTC
   workflow_dispatch: {}
 
-# Global permissions to fix "Exit Code 4" and CodeQL alerts
 permissions:
-  actions: write    # Crucial: Allows the 'gh' CLI to delete caches
-  contents: read   # Standard: Allows reading repo metadata
+  actions: write    
+  contents: read  
 
 jobs:
   cleanup:
diff --git a/ITERATIONS/README.md b/ITERATIONS/README.md
index c2ff28c..05be4eb 100644
--- a/ITERATIONS/README.md
+++ b/ITERATIONS/README.md
@@ -88,3 +88,52 @@ docker run --rm -i \
   -v $(pwd):/results \
   grafana/k6 run --summary-export=/results/result.json - <writeFile.js
 ```
+
+---
+
+## Real-World Capacity Analysis (1.5M Stress Test)
+
+Based on the final endurance run using 100 Virtual Users (VUs) and 1.5 Million iterations, we can calculate the sustained real-world capacity of the engine.
+
+### The "Concurrent User" Calculation
+
+To translate raw Requests Per Second (RPS) into Real Human Users, we apply the industry-standard "Think Time" model. We assume a typical user interacts with the application once every 5 seconds.
+
+| Metric               | Value         | Description                                   |
+|--------------------- |-------------- |-----------------------------------------------|
+| Peak Throughput      | 7,067 RPS     | Sustained rate over 1.5M requests             |
+| Think Time           | 5 Seconds     | Average delay between user actions            |
+| Calculated Capacity  | ~35,335 Users | Total concurrent users supported              |
+
+#### Performance Scaling Curve: VUs vs. Throughput (RPS)
+
+```text
+RPS (Throughput)
+  ^
+  |          (B) Peak Efficiency (7,242 RPS)
+  |               /----------\
+  |              /            \
+  |             /              \ (C) Contention/Saturation (7,067 RPS)
+  |            /                \--------------------
+  |           /
+  |    (A)   /
+  |         /
+  |        /
+  |  -----/
+  +------------------------------------------------------------> VUs (Concurrency)
+     1      4      8              20             100
+```
+
+---
+
+### Key Takeaways for 1.5M / 100 VUs
+
+- Massive Concurrency: Even when the system is under extreme artificial pressure (100 VUs fighting for 8 physical cores), the engine maintains a throughput that can support over 35,000 active humans simultaneously.
+
+- Infrastructure Efficiency: Processing 1.5 million requests with zero failures on a fanless MacBook Air M2 demonstrates that the native C++ core eliminates the overhead typically associated with high-frequency string processing in managed languages.
+
+- Hardware Saturation: The jump in p95 latency to 41ms (from 2.66ms at lower loads) indicates that while the CPU is fully saturated, the system remains highly responsive for web standards—95% of users still experience "sub-50ms" response times.
+
+### Final Verdict
+
+This engine, running on consumer-grade Apple Silicon, is capable of powering a Tier-1 Web Service backend. It provides the throughput of a distributed cluster within a single, highly optimized polyglot process.

From 457bd6c3100c962f52eb80a6e25be656e22eecd3 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 11:23:33 +0530
Subject: [PATCH 09/14] ci: finalize cache cleanup workflow with correct
 permissions and token scope

---
 .github/workflows/cleanup-cache.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index a67fe61..a2962c6 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -40,7 +40,8 @@ jobs:
 
       - name: Delete Old Caches
         env:
-          GH_TOKEN: ${{ secrets.SECRET_GITHUB_TOKEN }}
+          # Change SECRET_GITHUB_TOKEN to GITHUB_TOKEN
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
           REPO=${{ github.repository }}
 

From 4d6c7634499b1ccdc42800b04d63f34b7370e23d Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 11:28:12 +0530
Subject: [PATCH 10/14] ci: finalize cache cleanup workflow

---
 .github/workflows/cleanup-cache.yml | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index a2962c6..8ff046c 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -32,6 +32,8 @@ permissions:
 jobs:
   cleanup:
     runs-on: ubuntu-latest
+    env:
+      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
     steps:
       - name: Install Cache Extension
@@ -39,26 +41,18 @@ jobs:
           gh extension install actions/gh-actions-cache
 
       - name: Delete Old Caches
-        env:
-          # Change SECRET_GITHUB_TOKEN to GITHUB_TOKEN
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
           REPO=${{ github.repository }}
-
           echo "Fetching cache list for $REPO..."
-          # Fetch the list of caches
+          
           gh actions-cache list -R $REPO --limit 1000 > caches.txt
 
           while read -r line; do
-            # Extract Cache Key and Last Used Timestamp
             KEY=$(echo $line | awk '{print $1}')
             LAST_USED=$(echo $line | awk '{print $3" "$4}')
 
-            # Convert to Timestamps
             LAST_USED_TS=$(date -d "$LAST_USED" +%s || echo 0)
             NOW_TS=$(date +%s)
-
-            # Calculate Age in Days
             AGE=$(( (NOW_TS - LAST_USED_TS) / 86400 ))
 
             if [ "$AGE" -gt 7 ]; then

From d3456b2b593a2a8b1baf35c27b6705cef0f1c62e Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 15:08:27 +0530
Subject: [PATCH 11/14] ci: finalize cache cleanup workflow

---
 .github/workflows/cleanup-cache.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index 8ff046c..507e9b9 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -45,7 +45,7 @@ jobs:
           REPO=${{ github.repository }}
           echo "Fetching cache list for $REPO..."
           
-          gh actions-cache list -R $REPO --limit 1000 > caches.txt
+          gh actions-cache list -R $REPO --limit 100 > caches.txt
 
           while read -r line; do
             KEY=$(echo $line | awk '{print $1}')

From a3f32613a24b007c7d110a970c84cd49830b53b0 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 15:27:09 +0530
Subject: [PATCH 12/14] ci: finalize cache cleanup workflow

---
 .github/workflows/cleanup-cache.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
index 507e9b9..922b331 100644
--- a/.github/workflows/cleanup-cache.yml
+++ b/.github/workflows/cleanup-cache.yml
@@ -22,7 +22,7 @@ name: Cache Cleanup
 
 on:
   schedule:
-    - cron: '0 0 * * *' # Daily at midnight UTC
+    - cron: '30 18 * * *' # Midnight IST (18:30 UTC)
   workflow_dispatch: {}
 
 permissions:

From b1d7aa86fc486231b279d1222fb2ad4c62f59c75 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 16:44:02 +0530
Subject: [PATCH 13/14] Minor DLL changes

---
 .../CppLib/include/ProcessStringDLL.hpp         |  2 +-
 .../CppLib/src/ProcessStringDLL.cpp             | 17 ++++++++++-------
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/backend/CaseConversionAPI/CppLib/include/ProcessStringDLL.hpp b/backend/CaseConversionAPI/CppLib/include/ProcessStringDLL.hpp
index 97b2dc8..1456b92 100644
--- a/backend/CaseConversionAPI/CppLib/include/ProcessStringDLL.hpp
+++ b/backend/CaseConversionAPI/CppLib/include/ProcessStringDLL.hpp
@@ -47,7 +47,7 @@ extern "C" {
 #endif
 
 /**
- * @brief COnverts input string based on choice and returns a newly allocated
+ * @brief Converts input string based on choice and returns a newly allocated
  * C-string.
  *
  * @param input  C-string input.
diff --git a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
index d728a3d..e8d8e1b 100644
--- a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
@@ -78,7 +78,7 @@ static const char *safeError(const char *msg) {
 // Conversion Mapping (Internal - C++ only)
 //===================================================================
 
-static bool mapConversionType(ConversionChoice choice, ConversionType &type) {
+static bool mapConversionType(ConversionChoice choice, ConversionType &type) noexcept{
   switch (choice) {
   case ConversionChoice::Alternating:
     type = ConversionType::Alternating;
@@ -133,9 +133,10 @@ extern "C" {
 API const char *processStringDLL(const char *input, int choiceInt,
                                  const char *traceId) {
   try {
-    if (!input)
+    if (!input) {
       return safeError("ERROR_NULL_INPUT");
-
+    }
+      
     size_t inputLength = std::strlen(input);
     if (inputLength > MAX_INPUT_SIZE) {
       return safeError("ERROR_BUFFER_OVERFLOW_LIMIT_5MB");
@@ -162,15 +163,17 @@ API const char *processStringDLL(const char *input, int choiceInt,
     ConversionResult result = client.execute(std::string(input));
     const char *rawPtr = result.get_c_str();
 
-    if (!rawPtr)
+    if (!rawPtr) {
       return safeError("ERROR_ENGINE_RETURNED_NULL");
-
+    }
+      
     size_t resLen = std::strlen(rawPtr);
     char *output = static_cast<char *>(std::malloc(resLen + 1));
 
-    if (!output)
+    if (!output) {
       return safeError("FATAL_ALLOCATION_FAILURE");
-
+    }
+      
     std::memcpy(output, rawPtr, resLen + 1);
 
     return output;

From 8a643126f2ab3526b911f45a2e223938b1eae4a6 Mon Sep 17 00:00:00 2001
From: Nitish Singh <93253740+nitishhsinghhh@users.noreply.github.com>
Date: Mon, 4 May 2026 18:13:22 +0530
Subject: [PATCH 14/14] Resolved merge conflicts for handover

---
 .../CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp    | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
index e8d8e1b..0e69ac5 100644
--- a/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
+++ b/backend/CaseConversionAPI/CppLib/src/ProcessStringDLL.cpp
@@ -78,7 +78,8 @@ static const char *safeError(const char *msg) {
 // Conversion Mapping (Internal - C++ only)
 //===================================================================
 
-static bool mapConversionType(ConversionChoice choice, ConversionType &type) noexcept{
+static bool mapConversionType(ConversionChoice choice,
+                              ConversionType &type) noexcept {
   switch (choice) {
   case ConversionChoice::Alternating:
     type = ConversionType::Alternating;
@@ -136,7 +137,7 @@ API const char *processStringDLL(const char *input, int choiceInt,
     if (!input) {
       return safeError("ERROR_NULL_INPUT");
     }
-      
+
     size_t inputLength = std::strlen(input);
     if (inputLength > MAX_INPUT_SIZE) {
       return safeError("ERROR_BUFFER_OVERFLOW_LIMIT_5MB");
@@ -166,14 +167,14 @@ API const char *processStringDLL(const char *input, int choiceInt,
     if (!rawPtr) {
       return safeError("ERROR_ENGINE_RETURNED_NULL");
     }
-      
+
     size_t resLen = std::strlen(rawPtr);
     char *output = static_cast<char *>(std::malloc(resLen + 1));
 
     if (!output) {
       return safeError("FATAL_ALLOCATION_FAILURE");
     }
-      
+
     std::memcpy(output, rawPtr, resLen + 1);
 
     return output;