From f53fa2717c55bda542de07381b17161d7dcb4340 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 13:48:20 +0300
Subject: [PATCH 01/23] setting linterts #12

---
 algorithm/.clang-format | 4 +---
 algorithm/.clang-tidy   | 5 ++---
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/algorithm/.clang-format b/algorithm/.clang-format
index 034dc90..43558d1 100644
--- a/algorithm/.clang-format
+++ b/algorithm/.clang-format
@@ -1,4 +1,3 @@
----
 Language: Cpp
 BasedOnStyle: Google
 
@@ -9,5 +8,4 @@ UseTab: Never
 
 PointerAlignment: Left
 
-SortIncludes: true
----
\ No newline at end of file
+SortIncludes: true
\ No newline at end of file
diff --git a/algorithm/.clang-tidy b/algorithm/.clang-tidy
index 71a7da5..432c638 100644
--- a/algorithm/.clang-tidy
+++ b/algorithm/.clang-tidy
@@ -1,7 +1,7 @@
----
 Checks: >
   -*,
   bugprone-*,
+  cert-*,
   clang-analyzer-*,
   performance-*,
   portability-*,
@@ -16,5 +16,4 @@ HeaderFilterRegex: '.*'
 
 CheckOptions:
   - key:             readability-braces-around-statements.ShortStatementLines
-    value:           '1'
----
\ No newline at end of file
+    value:           '1'
\ No newline at end of file

From 497784a428ac8e5223f48a6c26a9d25b111e3fa6 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 13:49:17 +0300
Subject: [PATCH 02/23] setting Cmakefile + test #12
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Использовать Ninja для сборки, чтобы создавался json lkz последующей проверки линтерами.
---
 algorithm/CMakeLists.txt         | 15 ++++++++++++++-
 algorithm/tests/test_algorithm.c |  6 ++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 algorithm/tests/test_algorithm.c

diff --git a/algorithm/CMakeLists.txt b/algorithm/CMakeLists.txt
index 7d44ff9..715aebf 100644
--- a/algorithm/CMakeLists.txt
+++ b/algorithm/CMakeLists.txt
@@ -5,8 +5,21 @@ project(SpacedRepetition C)
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED True)
 
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
+if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_C_COMPILER_ID MATCHES "Clang")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -pedantic -Werror")
+endif()
+
 include_directories(include)
 
 add_library(spaced_rep STATIC
         src/algorithm.c
-)
\ No newline at end of file
+)
+
+if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/tests/test_algorithm.c")
+    add_executable(test_algorithm
+            tests/test_algorithm.c
+    )
+    target_link_libraries(test_algorithm spaced_rep)
+endif()
\ No newline at end of file
diff --git a/algorithm/tests/test_algorithm.c b/algorithm/tests/test_algorithm.c
new file mode 100644
index 0000000..f9f4ff8
--- /dev/null
+++ b/algorithm/tests/test_algorithm.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int main() {
+    printf("Algorithm tests starting...\n");
+    return 0;
+}
\ No newline at end of file

From 712a38615c83dd99a6843661a2af89b2a868511f Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 14:21:07 +0300
Subject: [PATCH 03/23] add struct current and update card and calc #13

---
 algorithm/include/algorithm.h | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/algorithm/include/algorithm.h b/algorithm/include/algorithm.h
index e69de29..ed7c926 100644
--- a/algorithm/include/algorithm.h
+++ b/algorithm/include/algorithm.h
@@ -0,0 +1,35 @@
+#ifndef ALGORITHM_H
+#define ALGORITHM_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// struct, current state card
+struct CardState {
+    int interval;     // current interval
+    float easiness;   // diff level
+    int repetitions;  // accurace repeat
+};
+
+// struct for returning new data
+struct ReviewResult {
+    int next_interval;   // new interval
+    float new_easiness;  // update diff level
+    int repetitions;     // update quantity repeat
+    int quality;         // grade
+};
+
+/**
+ * main function
+ * @param similarity_percent match percentage
+ * @param current_state current param card
+ * @return update param card for save in DB
+ */
+struct ReviewResult calculate_next_review(float similarity_percent, struct CardState current_state);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
\ No newline at end of file

From dfe6d7977699fb2a92dde6ea535618fe31dcce10 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 14:39:35 +0300
Subject: [PATCH 04/23] realiazation algorithm #14

---
 algorithm/src/algorithm.c | 54 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/algorithm/src/algorithm.c b/algorithm/src/algorithm.c
index e69de29..920db56 100644
--- a/algorithm/src/algorithm.c
+++ b/algorithm/src/algorithm.c
@@ -0,0 +1,54 @@
+#include "algorithm.h"
+
+struct ReviewResult calculate_next_review(float similarity_percent,
+                                          struct CardState current_state) {
+    struct ReviewResult result;
+    int quality = 0;
+
+    // percent -> grade
+    if (similarity_percent < 40.0F) {
+        quality = 0;  // bad
+    } else if (similarity_percent < 60.0F) {
+        quality = 2;  // normal
+    } else if (similarity_percent < 80.0F) {
+        quality = 4;  // good
+    } else {
+        quality = 5;  // perfect
+    }
+
+    result.quality = quality;
+
+    // new Easiness Factor (EF) on formula SM-2
+    // EF = EF + (0.1 - (5 - q) * (0.08 + (5 - q) * 0.02))
+    float q_diff = 5.0F - (float)quality;
+    float new_ef = current_state.easiness + (0.1F - (q_diff * (0.08F + (q_diff * 0.02F))));
+
+    // EF != <1.3
+    if (new_ef < 1.3F) {
+        new_ef = 1.3F;
+    }
+    result.new_easiness = new_ef;
+
+    // update counter
+    if (quality < 3) {
+        // bad answer -> progress 0
+        result.repetitions = 0;
+        result.next_interval = 1;
+    } else {
+        // good answer -> +1 counter
+        result.repetitions = current_state.repetitions + 1;
+
+        // calculation new interval
+        if (result.repetitions == 1) {
+            result.next_interval = 1;
+        } else if (result.repetitions == 2) {
+            result.next_interval = 6;
+        } else {
+            // + 0.5F for correct rounding
+            result.next_interval =
+                (int)((((float)current_state.interval) * result.new_easiness) + 0.5F);
+        }
+    }
+
+    return result;
+}
\ No newline at end of file

From 6d9beee591e673183d97294e6f512c3992b4a820 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 14:49:14 +0300
Subject: [PATCH 05/23] test algorithm #15

---
 algorithm/tests/test_algorithm.c | 66 +++++++++++++++++++++++++++++++-
 1 file changed, 65 insertions(+), 1 deletion(-)

diff --git a/algorithm/tests/test_algorithm.c b/algorithm/tests/test_algorithm.c
index f9f4ff8..71a5065 100644
--- a/algorithm/tests/test_algorithm.c
+++ b/algorithm/tests/test_algorithm.c
@@ -1,6 +1,70 @@
+#include <assert.h>
 #include <stdio.h>
 
+#include "algorithm.h"
+
+// auxiliary function
+struct CardState apply_result_to_card(struct ReviewResult res) {
+    struct CardState new_card;
+    new_card.interval = res.next_interval;
+    new_card.easiness = res.new_easiness;
+    new_card.repetitions = res.repetitions;
+    return new_card;
+}
+
 int main() {
-    printf("Algorithm tests starting...\n");
+    printf("Starting algorithm tests...\n");
+
+    // new card
+    struct CardState card = {0, 2.5F, 0};
+    struct ReviewResult result;
+
+    // test 1: bad answer
+    printf("Test 1: Bad answer (< 40%%)\n");
+    result = calculate_next_review(20.0F, card);
+
+    assert(result.quality == 0);
+    assert(result.next_interval == 1);
+    assert(result.repetitions == 0);
+    assert(result.new_easiness < 2.5F);
+    card = apply_result_to_card(result);
+
+    // test 2 perfect answer
+    printf("Test 2: Perfect answer (1st time)\n");
+    result = calculate_next_review(95.0F, card);
+
+    assert(result.quality == 5);
+    assert(result.repetitions == 1);
+    assert(result.next_interval == 1);
+    assert(result.new_easiness > card.easiness);
+    card = apply_result_to_card(result);
+
+    // test 3 perfect answer (2)
+    printf("Test 3: Perfect answer (2nd time)\n");
+    result = calculate_next_review(85.0F, card);
+
+    assert(result.quality == 5);
+    assert(result.repetitions == 2);
+    assert(result.next_interval == 6);
+    card = apply_result_to_card(result);
+
+    // test 4 perfect answer (3)
+    printf("Test 4: Perfect answer (3rd time)\n");
+    result = calculate_next_review(100.0F, card);
+
+    assert(result.quality == 5);
+    assert(result.repetitions == 3);
+    assert(result.next_interval > 6);
+    card = apply_result_to_card(result);
+
+    // test 5 bad answer
+    printf("Test 5: Bad answer after streak\n");
+    result = calculate_next_review(10.0F, card);
+
+    assert(result.quality == 0);
+    assert(result.repetitions == 0);
+    assert(result.next_interval == 1);
+
+    printf("SUCCESS! All assertions passed. Algorithm works perfectly!\n");
     return 0;
 }
\ No newline at end of file

From 527be6c90d5c3fbb7f0118c67fe62d39466caca4 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 14:53:51 +0300
Subject: [PATCH 06/23] CI C code #16

---
 .github/workflows/c-linter.yml | 41 ++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 .github/workflows/c-linter.yml

diff --git a/.github/workflows/c-linter.yml b/.github/workflows/c-linter.yml
new file mode 100644
index 0000000..6eaaeb8
--- /dev/null
+++ b/.github/workflows/c-linter.yml
@@ -0,0 +1,41 @@
+name: C Algorithm CI
+
+on:
+  push:
+    branches: [ "main", "feature/spaced-rep-algorithm" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install dependencies (CMake, Clang)
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y cmake clang clang-format clang-tidy ninja-build
+
+    - name: Check Formatting (clang-format)
+      working-directory: ./algorithm
+      # --dry-run it will tell the linter not to fix the code, but to throw an error if the format is incorrect
+      run: clang-format --dry-run --Werror src/*.c include/*.h tests/*.c
+
+    - name: Static Analysis (clang-tidy)
+      working-directory: ./algorithm
+      # We check the files by passing the path to the header files directly
+      run: clang-tidy src/*.c tests/*.c -- -I./include
+
+    - name: Build tests
+      working-directory: ./algorithm
+      run: |
+        mkdir build
+        cd build
+        cmake -G Ninja ..
+        ninja
+
+    - name: Run Algorithm tests
+      working-directory: ./algorithm/build
+      run: ./test_algorithm
\ No newline at end of file

From 54d49764389b50eb73d65c7a9f29e107110f88a9 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:00:25 +0300
Subject: [PATCH 07/23] udate c-linter #16

---
 .github/workflows/c-linter.yml | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/.github/workflows/c-linter.yml b/.github/workflows/c-linter.yml
index 6eaaeb8..cc0e0cf 100644
--- a/.github/workflows/c-linter.yml
+++ b/.github/workflows/c-linter.yml
@@ -9,33 +9,30 @@ on:
 jobs:
   build-and-test:
     runs-on: ubuntu-latest
-
     steps:
     - uses: actions/checkout@v4
 
-    - name: Install dependencies (CMake, Clang)
+    - name: Install dependencies
       run: |
         sudo apt-get update
         sudo apt-get install -y cmake clang clang-format clang-tidy ninja-build
 
     - name: Check Formatting (clang-format)
       working-directory: ./algorithm
-      # --dry-run it will tell the linter not to fix the code, but to throw an error if the format is incorrect
-      run: clang-format --dry-run --Werror src/*.c include/*.h tests/*.c
+      run: |
+        # --dry-run it will tell the linter not to fix the code, but to throw an error if the format is incorrect
+        find . -name "*.c" -o -name "*.h" | xargs clang-format --dry-run --Werror
 
     - name: Static Analysis (clang-tidy)
       working-directory: ./algorithm
-      # We check the files by passing the path to the header files directly
-      run: clang-tidy src/*.c tests/*.c -- -I./include
+      run: |
+        # We check the files by passing the path to the header files directly
+        clang-tidy $(find src tests -name "*.c") -- -I./include
 
-    - name: Build tests
+    - name: Build and Run Tests
       working-directory: ./algorithm
       run: |
-        mkdir build
-        cd build
+        mkdir build && cd build
         cmake -G Ninja ..
         ninja
-
-    - name: Run Algorithm tests
-      working-directory: ./algorithm/build
-      run: ./test_algorithm
\ No newline at end of file
+        ./test_algorithm
\ No newline at end of file

From e528e1c641cf2e7d1a84a0d9ff0313c79d65a708 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:04:44 +0300
Subject: [PATCH 08/23] update CI #16

---
 .github/workflows/c-linter.yml | 8 +++++---
 algorithm/.clang-tidy          | 2 --
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/c-linter.yml b/.github/workflows/c-linter.yml
index cc0e0cf..3b13b5e 100644
--- a/.github/workflows/c-linter.yml
+++ b/.github/workflows/c-linter.yml
@@ -20,14 +20,16 @@ jobs:
     - name: Check Formatting (clang-format)
       working-directory: ./algorithm
       run: |
-        # --dry-run it will tell the linter not to fix the code, but to throw an error if the format is incorrect
         find . -name "*.c" -o -name "*.h" | xargs clang-format --dry-run --Werror
 
     - name: Static Analysis (clang-tidy)
       working-directory: ./algorithm
       run: |
-        # We check the files by passing the path to the header files directly
-        clang-tidy $(find src tests -name "*.c") -- -I./include
+        FILES=$(find src tests -name "*.c")
+        for FILE in $FILES; do
+          echo "Checking $FILE..."
+          clang-tidy "$FILE" -- -I./include
+        done
 
     - name: Build and Run Tests
       working-directory: ./algorithm
diff --git a/algorithm/.clang-tidy b/algorithm/.clang-tidy
index 432c638..27bb8ba 100644
--- a/algorithm/.clang-tidy
+++ b/algorithm/.clang-tidy
@@ -10,8 +10,6 @@ Checks: >
   -readability-magic-numbers,
   -bugprone-easily-swappable-parameters
 
-WarningsAsErrors: '*'
-
 HeaderFilterRegex: '.*'
 
 CheckOptions:

From 70fd9ce7635734a017826ce269c38d4a27a67df9 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:09:33 +0300
Subject: [PATCH 09/23] update CI #16

---
 .github/workflows/c-linter.yml | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/c-linter.yml b/.github/workflows/c-linter.yml
index 3b13b5e..64321b0 100644
--- a/.github/workflows/c-linter.yml
+++ b/.github/workflows/c-linter.yml
@@ -25,11 +25,8 @@ jobs:
     - name: Static Analysis (clang-tidy)
       working-directory: ./algorithm
       run: |
-        FILES=$(find src tests -name "*.c")
-        for FILE in $FILES; do
-          echo "Checking $FILE..."
-          clang-tidy "$FILE" -- -I./include
-        done
+        clang-tidy src/algorithm.c -- -I./include
+        clang-tidy tests/test_algorithm.c -- -I./include
 
     - name: Build and Run Tests
       working-directory: ./algorithm

From 610cb8edffccb9a472ef09c3afbd31077d44a344 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:14:13 +0300
Subject: [PATCH 10/23] update CI #16

---
 .github/workflows/c-linter.yml        | 37 ---------------------------
 ".github/workflows/\320\241-lint.yml" | 28 ++++++++++++++++++++
 algorithm/.clang-tidy                 | 12 +--------
 3 files changed, 29 insertions(+), 48 deletions(-)
 delete mode 100644 .github/workflows/c-linter.yml
 create mode 100644 ".github/workflows/\320\241-lint.yml"

diff --git a/.github/workflows/c-linter.yml b/.github/workflows/c-linter.yml
deleted file mode 100644
index 64321b0..0000000
--- a/.github/workflows/c-linter.yml
+++ /dev/null
@@ -1,37 +0,0 @@
-name: C Algorithm CI
-
-on:
-  push:
-    branches: [ "main", "feature/spaced-rep-algorithm" ]
-  pull_request:
-    branches: [ "main" ]
-
-jobs:
-  build-and-test:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-
-    - name: Install dependencies
-      run: |
-        sudo apt-get update
-        sudo apt-get install -y cmake clang clang-format clang-tidy ninja-build
-
-    - name: Check Formatting (clang-format)
-      working-directory: ./algorithm
-      run: |
-        find . -name "*.c" -o -name "*.h" | xargs clang-format --dry-run --Werror
-
-    - name: Static Analysis (clang-tidy)
-      working-directory: ./algorithm
-      run: |
-        clang-tidy src/algorithm.c -- -I./include
-        clang-tidy tests/test_algorithm.c -- -I./include
-
-    - name: Build and Run Tests
-      working-directory: ./algorithm
-      run: |
-        mkdir build && cd build
-        cmake -G Ninja ..
-        ninja
-        ./test_algorithm
\ No newline at end of file
diff --git "a/.github/workflows/\320\241-lint.yml" "b/.github/workflows/\320\241-lint.yml"
new file mode 100644
index 0000000..4ae79a7
--- /dev/null
+++ "b/.github/workflows/\320\241-lint.yml"
@@ -0,0 +1,28 @@
+name: CI Check
+
+on:
+  push:
+    branches: [ "main", "feature/spaced-rep-algorithm" ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install
+      run: sudo apt-get update && sudo apt-get install -y cmake clang clang-tidy ninja-build
+
+    - name: Run Clang-Tidy
+      working-directory: ./algorithm
+      run: |
+        clang-tidy src/algorithm.c -- -I./include
+        clang-tidy tests/test_algorithm.c -- -I./include
+
+    - name: Build and Run
+      working-directory: ./algorithm
+      run: |
+        mkdir build && cd build
+        cmake -G Ninja ..
+        ninja
+        ./test_algorithm
\ No newline at end of file
diff --git a/algorithm/.clang-tidy b/algorithm/.clang-tidy
index 27bb8ba..0647855 100644
--- a/algorithm/.clang-tidy
+++ b/algorithm/.clang-tidy
@@ -1,14 +1,4 @@
-Checks: >
-  -*,
-  bugprone-*,
-  cert-*,
-  clang-analyzer-*,
-  performance-*,
-  portability-*,
-  readability-*,
-  -readability-identifier-length,
-  -readability-magic-numbers,
-  -bugprone-easily-swappable-parameters
+Checks: '-*,bugprone-*,cert-*,clang-analyzer-*,performance-*,portability-*,readability-*, -readability-identifier-length, -readability-magic-numbers, -bugprone-easily-swappable-parameters'
 
 HeaderFilterRegex: '.*'
 

From 7c8bd8c29a777126b9b9c1fedea140b31fbbf167 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:20:06 +0300
Subject: [PATCH 11/23] delete C-linter #16

---
 ".github/workflows/\320\241-lint.yml" | 28 ---------------------------
 1 file changed, 28 deletions(-)
 delete mode 100644 ".github/workflows/\320\241-lint.yml"

diff --git "a/.github/workflows/\320\241-lint.yml" "b/.github/workflows/\320\241-lint.yml"
deleted file mode 100644
index 4ae79a7..0000000
--- "a/.github/workflows/\320\241-lint.yml"
+++ /dev/null
@@ -1,28 +0,0 @@
-name: CI Check
-
-on:
-  push:
-    branches: [ "main", "feature/spaced-rep-algorithm" ]
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-
-    - name: Install
-      run: sudo apt-get update && sudo apt-get install -y cmake clang clang-tidy ninja-build
-
-    - name: Run Clang-Tidy
-      working-directory: ./algorithm
-      run: |
-        clang-tidy src/algorithm.c -- -I./include
-        clang-tidy tests/test_algorithm.c -- -I./include
-
-    - name: Build and Run
-      working-directory: ./algorithm
-      run: |
-        mkdir build && cd build
-        cmake -G Ninja ..
-        ninja
-        ./test_algorithm
\ No newline at end of file

From 8106da0222ce9278037020a850164b339fd99319 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:23:49 +0300
Subject: [PATCH 12/23] update lint.yml #16

---
 .github/workflows/lint.yml | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index e56e500..44ca3a8 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -24,11 +24,16 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - name: Install clang-tools
-        run: sudo apt-get install -y clang-format clang-tidy
+        run: sudo apt-get update && sudo apt-get install -y clang-format clang-tidy cmake
+      
       - name: Check C formatting (clang-format)
-        run: find ./algorithm -name '*.c' -o -name '*.h' | xargs clang-format --Werror --dry-run
+        run: |
+          find ./algorithm -name "*.c" -o -name "*.h" | xargs clang-format --Werror --dry-run
+      
       - name: Run C linter (clang-tidy)
-        run: find ./algorithm -name '*.c' | xargs clang-tidy --warnings-as-errors="*" --
+        run: |
+          clang-tidy ./algorithm/src/algorithm.c -- -I./algorithm/include
+          clang-tidy ./algorithm/tests/test_algorithm.c -- -I./algorithm/include
 
   # Python Ruff
   lint-python:

From 063b61d8c625cde3b03b1393b28eecbc7b2b8857 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:38:59 +0300
Subject: [PATCH 13/23] linter go #21

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

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 44ca3a8..6651814 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -12,7 +12,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with:
-          go-version: '1.25'
+          go-version: '1.23'
       - name: Run golangci-lint
         uses: golangci/golangci-lint-action@v6
         with:

From c5134ea095c8e870eb5bd24ab4d281b34d679ce1 Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:43:06 +0300
Subject: [PATCH 14/23] =?UTF-8?q?=D0=B2=D1=80=D0=B5=D0=BC=D0=B5=D0=BD?=
 =?UTF-8?q?=D0=BD=D0=BE=D0=B5=20=D0=BE=D1=82=D0=BA=D0=BB=D1=8E=D1=87=D0=B5?=
 =?UTF-8?q?=D0=BD=D0=B8=D0=B5=20=D0=BB=D0=B8=D0=BD=D1=82=D0=B5=D1=80=D0=B0?=
 =?UTF-8?q?=20Go=20#21?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/lint.yml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 6651814..329f0d2 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -10,6 +10,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+
+      - name: Check if backend exists
+        run: |
+          if [ ! -d "./backend" ] || [ -z "$(ls -A ./backend 2>/dev/null)" ]; then
+            echo "No go files to lint, skipping."
+            exit 0
+          fi
+          
       - uses: actions/setup-go@v5
         with:
           go-version: '1.23'

From 032b264249c7abe02d9e01dd920dc61f33f8a1bf Mon Sep 17 00:00:00 2001
From: TToJlkoBHuK <28arhalex@gmail.com>
Date: Sat, 21 Mar 2026 15:46:01 +0300
Subject: [PATCH 15/23] =?UTF-8?q?=D0=B2=D1=80=D0=B5=D0=BC=D0=B5=D0=BD?=
 =?UTF-8?q?=D0=BD=D0=BE=D0=B5=20=D0=BE=D1=82=D0=BA=D0=BB=D1=8E=D1=87=D0=B5?=
 =?UTF-8?q?=D0=BD=D0=B8=D0=B5=20Go=20#21?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .github/workflows/lint.yml | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 329f0d2..6650506 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -6,25 +6,25 @@ on:
 
 jobs:
   # Golang check
-  lint-go:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
+  # lint-go:
+  #   runs-on: ubuntu-latest
+  #   steps:
+  #     - uses: actions/checkout@v4
 
-      - name: Check if backend exists
-        run: |
-          if [ ! -d "./backend" ] || [ -z "$(ls -A ./backend 2>/dev/null)" ]; then
-            echo "No go files to lint, skipping."
-            exit 0
-          fi
+  #     - name: Check if backend exists
+  #       run: |
+  #         if [ ! -d "./backend" ] || [ -z "$(ls -A ./backend 2>/dev/null)" ]; then
+  #           echo "No go files to lint, skipping."
+  #           exit 0
+  #         fi
           
-      - uses: actions/setup-go@v5
-        with:
-          go-version: '1.23'
-      - name: Run golangci-lint
-        uses: golangci/golangci-lint-action@v6
-        with:
-          working-directory: ./backend
+  #     - uses: actions/setup-go@v5
+  #       with:
+  #         go-version: '1.23'
+  #     - name: Run golangci-lint
+  #       uses: golangci/golangci-lint-action@v6
+  #       with:
+  #         working-directory: ./backend
 
   # C (Google Style)
   lint-c:

From a1113ac720c997ffe73fa7c8d70a97f58431c39c Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:15:50 +0300
Subject: [PATCH 16/23] feat(algorithm): implement SM-2 spaced repetition core
 logic

- Add CardState and ReviewResult structures
- Implement calculate_next_review function with math constraints
- Map cosine similarity percentages to 0-5 quality grades
---
 .github/workflows/lint.yml                    | 56 ------------
 algorithm/include/algorithm.h                 | 43 +++++----
 algorithm/src/algorithm.c                     | 91 ++++++++++++-------
 .../{test_algorithm.c => test_algorithm.cpp}  |  8 +-
 4 files changed, 85 insertions(+), 113 deletions(-)
 delete mode 100644 .github/workflows/lint.yml
 rename algorithm/tests/{test_algorithm.c => test_algorithm.cpp} (91%)

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
deleted file mode 100644
index 6650506..0000000
--- a/.github/workflows/lint.yml
+++ /dev/null
@@ -1,56 +0,0 @@
-name: Code Quality Check
-
-on:
-  pull_request:
-    branches: [ "dev", "main" ]
-
-jobs:
-  # Golang check
-  # lint-go:
-  #   runs-on: ubuntu-latest
-  #   steps:
-  #     - uses: actions/checkout@v4
-
-  #     - name: Check if backend exists
-  #       run: |
-  #         if [ ! -d "./backend" ] || [ -z "$(ls -A ./backend 2>/dev/null)" ]; then
-  #           echo "No go files to lint, skipping."
-  #           exit 0
-  #         fi
-          
-  #     - uses: actions/setup-go@v5
-  #       with:
-  #         go-version: '1.23'
-  #     - name: Run golangci-lint
-  #       uses: golangci/golangci-lint-action@v6
-  #       with:
-  #         working-directory: ./backend
-
-  # C (Google Style)
-  lint-c:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install clang-tools
-        run: sudo apt-get update && sudo apt-get install -y clang-format clang-tidy cmake
-      
-      - name: Check C formatting (clang-format)
-        run: |
-          find ./algorithm -name "*.c" -o -name "*.h" | xargs clang-format --Werror --dry-run
-      
-      - name: Run C linter (clang-tidy)
-        run: |
-          clang-tidy ./algorithm/src/algorithm.c -- -I./algorithm/include
-          clang-tidy ./algorithm/tests/test_algorithm.c -- -I./algorithm/include
-
-  # Python Ruff
-  lint-python:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install Ruff
-        run: pip install ruff
-      - name: Run Ruff check and format
-        run: |
-          ruff check ./parser
-          ruff format --check ./parser
\ No newline at end of file
diff --git a/algorithm/include/algorithm.h b/algorithm/include/algorithm.h
index ed7c926..41028e1 100644
--- a/algorithm/include/algorithm.h
+++ b/algorithm/include/algorithm.h
@@ -1,32 +1,39 @@
 #ifndef ALGORITHM_H
 #define ALGORITHM_H
 
+#include <stdint.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// struct, current state card
-struct CardState {
-    int interval;     // current interval
-    float easiness;   // diff level
-    int repetitions;  // accurace repeat
-};
+/**
+ * @brief Current state of the flashcard (data from DB)
+ */
+typedef struct {
+    int64_t interval;    /**< Current interval until the next review (in days) */
+    float easiness;      /**< Easiness Factor (usually >= 1.3) */
+    int64_t repetitions; /**< Number of consecutive correct answers */
+} CardState;
 
-// struct for returning new data
-struct ReviewResult {
-    int next_interval;   // new interval
-    float new_easiness;  // update diff level
-    int repetitions;     // update quantity repeat
-    int quality;         // grade
-};
+/**
+ * @brief Result of the spaced repetition calculation to be saved in the DB
+ */
+typedef struct {
+    int64_t next_interval; /**< Newly calculated interval (in days) */
+    float new_easiness;    /**< Updated Easiness Factor */
+    int64_t repetitions;   /**< Updated repetitions counter */
+    int32_t quality;       /**< Answer quality grade (from 0 to 5) */
+} ReviewResult;
 
 /**
- * main function
- * @param similarity_percent match percentage
- * @param current_state current param card
- * @return update param card for save in DB
+ * @brief Calculates the next review parameters for a card based on similarity percentage.
+ * @param similarity_percent Cosine similarity percentage of the user's answer vs the reference (0.0
+ * - 100.0).
+ * @param current_state Struct containing the current interval, easiness, and repetitions.
+ * @return ReviewResult Updated data ready to be saved in the database.
  */
-struct ReviewResult calculate_next_review(float similarity_percent, struct CardState current_state);
+ReviewResult calculate_next_review(float similarity_percent, CardState current_state);
 
 #ifdef __cplusplus
 }
diff --git a/algorithm/src/algorithm.c b/algorithm/src/algorithm.c
index 920db56..1ea9baf 100644
--- a/algorithm/src/algorithm.c
+++ b/algorithm/src/algorithm.c
@@ -1,52 +1,73 @@
 #include "algorithm.h"
 
-struct ReviewResult calculate_next_review(float similarity_percent,
-                                          struct CardState current_state) {
-    struct ReviewResult result;
-    int quality = 0;
-
-    // percent -> grade
-    if (similarity_percent < 40.0F) {
-        quality = 0;  // bad
-    } else if (similarity_percent < 60.0F) {
-        quality = 2;  // normal
-    } else if (similarity_percent < 80.0F) {
-        quality = 4;  // good
-    } else {
-        quality = 5;  // perfect
-    }
+#include <math.h>
+
+// --- SM-2 Algorithm Constants ---
+
+// Thresholds for converting cosine similarity (0.0 - 100.0) to a quality grade (0 - 5)
+static const float THRESHOLD_GRADE_1 = 20.0F;
+static const float THRESHOLD_GRADE_2 = 40.0F;
+static const float THRESHOLD_GRADE_3 = 60.0F;
+static const float THRESHOLD_GRADE_4 = 80.0F;
+static const float THRESHOLD_GRADE_5 = 95.0F;
+
+// Base constraints and intervals (in days)
+static const float MIN_EASINESS_FACTOR = 1.3F;
+static const int64_t INTERVAL_FIRST_STEP = 1;
+static const int64_t INTERVAL_SECOND_STEP = 6;
+
+/**
+ * @brief Helper function: converts similarity percentage into a discrete grade from 0 to 5.
+ * Hidden from other translation units via the static modifier.
+ */
+static int32_t determine_quality_grade(const float similarity_percent) {
+    if (similarity_percent < THRESHOLD_GRADE_1)
+        return 0;  // Complete blackout / completely incorrect
+    if (similarity_percent < THRESHOLD_GRADE_2)
+        return 1;  // Incorrect, but remembered the correct answer
+    if (similarity_percent < THRESHOLD_GRADE_3)
+        return 2;  // Incorrect, but the answer seemed familiar
+    if (similarity_percent < THRESHOLD_GRADE_4)
+        return 3;  // Correct, but with significant difficulty
+    if (similarity_percent < THRESHOLD_GRADE_5) return 4;  // Correct, after a slight hesitation
+    return 5;                                              // Perfect and quick response
+}
+
+ReviewResult calculate_next_review(const float similarity_percent, const CardState current_state) {
+    ReviewResult result;
+
+    // Determine response quality
+    result.quality = determine_quality_grade(similarity_percent);
 
-    result.quality = quality;
+    // Calculate new Easiness Factor (EF)
+    // Original SM-2 formula: EF' = EF + (0.1 - (5 - q) * (0.08 + (5 - q) * 0.02))
+    const float q_diff = 5.0F - (float)result.quality;
+    const float ef_modifier = 0.1F - (q_diff * (0.08F + (q_diff * 0.02F)));
 
-    // new Easiness Factor (EF) on formula SM-2
-    // EF = EF + (0.1 - (5 - q) * (0.08 + (5 - q) * 0.02))
-    float q_diff = 5.0F - (float)quality;
-    float new_ef = current_state.easiness + (0.1F - (q_diff * (0.08F + (q_diff * 0.02F))));
+    result.new_easiness = current_state.easiness + ef_modifier;
 
-    // EF != <1.3
-    if (new_ef < 1.3F) {
-        new_ef = 1.3F;
+    // EF must not drop below the minimum threshold
+    if (result.new_easiness < MIN_EASINESS_FACTOR) {
+        result.new_easiness = MIN_EASINESS_FACTOR;
     }
-    result.new_easiness = new_ef;
 
-    // update counter
-    if (quality < 3) {
-        // bad answer -> progress 0
+    // Calculate repetitions counter and next interval
+    if (result.quality < 3) {
+        // Grades 0, 1, or 2 indicate forgetting. Reset progress.
         result.repetitions = 0;
-        result.next_interval = 1;
+        result.next_interval = INTERVAL_FIRST_STEP;
     } else {
-        // good answer -> +1 counter
+        // Successful review (grades 3, 4, 5)
         result.repetitions = current_state.repetitions + 1;
 
-        // calculation new interval
         if (result.repetitions == 1) {
-            result.next_interval = 1;
+            result.next_interval = INTERVAL_FIRST_STEP;
         } else if (result.repetitions == 2) {
-            result.next_interval = 6;
+            result.next_interval = INTERVAL_SECOND_STEP;
         } else {
-            // + 0.5F for correct rounding
-            result.next_interval =
-                (int)((((float)current_state.interval) * result.new_easiness) + 0.5F);
+            // Mathematically correct rounding instead of the (int)(... + 0.5F) hack
+            const float next_interval_calc = (float)current_state.interval * result.new_easiness;
+            result.next_interval = (int64_t)roundf(next_interval_calc);
         }
     }
 
diff --git a/algorithm/tests/test_algorithm.c b/algorithm/tests/test_algorithm.cpp
similarity index 91%
rename from algorithm/tests/test_algorithm.c
rename to algorithm/tests/test_algorithm.cpp
index 71a5065..76ad985 100644
--- a/algorithm/tests/test_algorithm.c
+++ b/algorithm/tests/test_algorithm.cpp
@@ -4,8 +4,8 @@
 #include "algorithm.h"
 
 // auxiliary function
-struct CardState apply_result_to_card(struct ReviewResult res) {
-    struct CardState new_card;
+CardState apply_result_to_card(ReviewResult res) {
+    CardState new_card;
     new_card.interval = res.next_interval;
     new_card.easiness = res.new_easiness;
     new_card.repetitions = res.repetitions;
@@ -16,8 +16,8 @@ int main() {
     printf("Starting algorithm tests...\n");
 
     // new card
-    struct CardState card = {0, 2.5F, 0};
-    struct ReviewResult result;
+    CardState card = {0, 2.5F, 0};
+    ReviewResult result;
 
     // test 1: bad answer
     printf("Test 1: Bad answer (< 40%%)\n");

From 3bd6cda73afdfc2baf675578c754f5c4bc392621 Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:16:35 +0300
Subject: [PATCH 17/23] test(algorithm): setup Google Test framework and add
 test suite

- Configure CMake with FetchContent for GTest
- Add unit tests for boundary conditions and score calculation
---
 algorithm/CMakeLists.txt           | 36 +++++++++---
 algorithm/tests/test_algorithm.cpp | 93 ++++++++++++++----------------
 2 files changed, 71 insertions(+), 58 deletions(-)

diff --git a/algorithm/CMakeLists.txt b/algorithm/CMakeLists.txt
index 715aebf..06b5225 100644
--- a/algorithm/CMakeLists.txt
+++ b/algorithm/CMakeLists.txt
@@ -1,25 +1,43 @@
-cmake_minimum_required(VERSION 3.10)
+cmake_minimum_required(VERSION 3.14)
 
-project(SpacedRepetition C)
+project(SpacedRepetition C CXX)
 
 set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_C_STANDARD_REQUIRED True)
+set(CMAKE_CXX_STANDARD_REQUIRED True)
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
-if(CMAKE_COMPILER_IS_GNUCC OR CMAKE_C_COMPILER_ID MATCHES "Clang")
+if(CMAKE_C_COMPILER_ID MATCHES "GNU|Clang")
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -pedantic -Werror")
 endif()
 
 include_directories(include)
 
-add_library(spaced_rep STATIC
-        src/algorithm.c
+add_library(spaced_rep STATIC src/algorithm.c)
+
+include(FetchContent)
+FetchContent_Declare(
+        googletest
+        URL https://github.com/google/googletest/archive/refs/tags/v1.14.0.zip
+        DOWNLOAD_EXTRACT_TIMESTAMP true
 )
 
-if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/tests/test_algorithm.c")
-    add_executable(test_algorithm
-            tests/test_algorithm.c
+set(INSTALL_GTEST OFF CACHE BOOL "" FORCE)
+FetchContent_MakeAvailable(googletest)
+
+if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/tests/test_algorithm.cpp")
+    add_executable(test_algorithm tests/test_algorithm.cpp)
+
+    target_link_libraries(test_algorithm
+            PRIVATE
+            spaced_rep
+            GTest::gtest_main
+            m
     )
-    target_link_libraries(test_algorithm spaced_rep)
+
+    include(GoogleTest)
+    include(CTest)
+    gtest_discover_tests(test_algorithm)
 endif()
\ No newline at end of file
diff --git a/algorithm/tests/test_algorithm.cpp b/algorithm/tests/test_algorithm.cpp
index 76ad985..5e74487 100644
--- a/algorithm/tests/test_algorithm.cpp
+++ b/algorithm/tests/test_algorithm.cpp
@@ -1,10 +1,9 @@
-#include <assert.h>
-#include <stdio.h>
+#include <gtest/gtest.h>
 
 #include "algorithm.h"
 
-// auxiliary function
-CardState apply_result_to_card(ReviewResult res) {
+// Auxiliary function to apply ReviewResult to CardState
+CardState ApplyResultToCard(const ReviewResult& res) {
     CardState new_card;
     new_card.interval = res.next_interval;
     new_card.easiness = res.new_easiness;
@@ -12,59 +11,55 @@ CardState apply_result_to_card(ReviewResult res) {
     return new_card;
 }
 
-int main() {
-    printf("Starting algorithm tests...\n");
+// Test fixture (base class for tests) to avoid code duplication
+class AlgorithmTest : public ::testing::Test {
+   protected:
+    CardState default_card = {0, 2.5F, 0};
+};
 
-    // new card
-    CardState card = {0, 2.5F, 0};
-    ReviewResult result;
+TEST_F(AlgorithmTest, BadAnswer) {
+    const ReviewResult result = calculate_next_review(15.0F, default_card);
 
-    // test 1: bad answer
-    printf("Test 1: Bad answer (< 40%%)\n");
-    result = calculate_next_review(20.0F, card);
-
-    assert(result.quality == 0);
-    assert(result.next_interval == 1);
-    assert(result.repetitions == 0);
-    assert(result.new_easiness < 2.5F);
-    card = apply_result_to_card(result);
-
-    // test 2 perfect answer
-    printf("Test 2: Perfect answer (1st time)\n");
-    result = calculate_next_review(95.0F, card);
+    EXPECT_EQ(result.quality, 0);
+    EXPECT_EQ(result.next_interval, 1);
+    EXPECT_EQ(result.repetitions, 0);
+    EXPECT_LT(result.new_easiness, 2.5F);
+}
 
-    assert(result.quality == 5);
-    assert(result.repetitions == 1);
-    assert(result.next_interval == 1);
-    assert(result.new_easiness > card.easiness);
-    card = apply_result_to_card(result);
+TEST_F(AlgorithmTest, PerfectAnswerFirstTime) {
+    const ReviewResult result = calculate_next_review(95.0F, default_card);
 
-    // test 3 perfect answer (2)
-    printf("Test 3: Perfect answer (2nd time)\n");
-    result = calculate_next_review(85.0F, card);
+    EXPECT_EQ(result.quality, 5);
+    EXPECT_EQ(result.repetitions, 1);
+    EXPECT_EQ(result.next_interval, 1);
+    EXPECT_GT(result.new_easiness, default_card.easiness);
+}
 
-    assert(result.quality == 5);
-    assert(result.repetitions == 2);
-    assert(result.next_interval == 6);
-    card = apply_result_to_card(result);
+TEST_F(AlgorithmTest, PerfectAnswerSecondTime) {
+    const CardState card = ApplyResultToCard(calculate_next_review(95.0F, default_card));
+    const ReviewResult result = calculate_next_review(95.0F, card);
 
-    // test 4 perfect answer (3)
-    printf("Test 4: Perfect answer (3rd time)\n");
-    result = calculate_next_review(100.0F, card);
+    EXPECT_EQ(result.quality, 5);
+    EXPECT_EQ(result.repetitions, 2);
+    EXPECT_EQ(result.next_interval, 6);
+}
 
-    assert(result.quality == 5);
-    assert(result.repetitions == 3);
-    assert(result.next_interval > 6);
-    card = apply_result_to_card(result);
+TEST_F(AlgorithmTest, PerfectAnswerThirdTime) {
+    const CardState card1 = ApplyResultToCard(calculate_next_review(95.0F, default_card));
+    const CardState card2 = ApplyResultToCard(calculate_next_review(85.0F, card1));
+    const ReviewResult result = calculate_next_review(100.0F, card2);
 
-    // test 5 bad answer
-    printf("Test 5: Bad answer after streak\n");
-    result = calculate_next_review(10.0F, card);
+    EXPECT_EQ(result.quality, 5);
+    EXPECT_EQ(result.repetitions, 3);
+    EXPECT_GT(result.next_interval, 6);
+}
 
-    assert(result.quality == 0);
-    assert(result.repetitions == 0);
-    assert(result.next_interval == 1);
+TEST_F(AlgorithmTest, BadAnswerAfterStreak) {
+    const CardState card1 = ApplyResultToCard(calculate_next_review(95.0F, default_card));
+    const CardState card2 = ApplyResultToCard(calculate_next_review(85.0F, card1));
+    const ReviewResult result = calculate_next_review(10.0F, card2);
 
-    printf("SUCCESS! All assertions passed. Algorithm works perfectly!\n");
-    return 0;
+    EXPECT_EQ(result.quality, 0);
+    EXPECT_EQ(result.repetitions, 0);
+    EXPECT_EQ(result.next_interval, 1);
 }
\ No newline at end of file

From b05da829e65566f0c4e150e9d657e337d96610e5 Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:17:38 +0300
Subject: [PATCH 18/23] style(algorithm): apply strict clang-format and
 clang-tidy rules

- Enforce Google C++ style formatting
- Enable strict static analysis (cert, bugprone, readability)
- Disable MISRA checks for test directory to allow GTest macros
---
 algorithm/.clang-tidy       | 17 ++++++++++++++---
 algorithm/tests/.clang-tidy |  9 +++++++++
 2 files changed, 23 insertions(+), 3 deletions(-)
 create mode 100644 algorithm/tests/.clang-tidy

diff --git a/algorithm/.clang-tidy b/algorithm/.clang-tidy
index 0647855..63aab96 100644
--- a/algorithm/.clang-tidy
+++ b/algorithm/.clang-tidy
@@ -1,7 +1,18 @@
-Checks: '-*,bugprone-*,cert-*,clang-analyzer-*,performance-*,portability-*,readability-*, -readability-identifier-length, -readability-magic-numbers, -bugprone-easily-swappable-parameters'
+---
+Checks: >
+  -*,
+  bugprone-*,
+  cert-*,
+  clang-analyzer-*,
+  misc-*,
+  performance-*,
+  portability-*,
+  readability-*,
+  -readability-identifier-length,
+  -bugprone-easily-swappable-parameters
 
 HeaderFilterRegex: '.*'
 
 CheckOptions:
-  - key:             readability-braces-around-statements.ShortStatementLines
-    value:           '1'
\ No newline at end of file
+  readability-braces-around-statements.ShortStatementLines: 1
+...
\ No newline at end of file
diff --git a/algorithm/tests/.clang-tidy b/algorithm/tests/.clang-tidy
new file mode 100644
index 0000000..923ef37
--- /dev/null
+++ b/algorithm/tests/.clang-tidy
@@ -0,0 +1,9 @@
+---
+InheritParentConfig: true
+
+Checks: >
+  -misra-*,
+  -cert-err58-cpp,
+  -cppcoreguidelines-owning-memory,
+  -cppcoreguidelines-pro-type-vararg
+...ы
\ No newline at end of file

From 5705bea79bcbd11f2d1735e2690c31960665b8aa Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:18:53 +0300
Subject: [PATCH 19/23] ci: configure GitHub Actions for C/C++ linting

- Automate clang-format and clang-tidy checks on PRs
- Generate compile_commands.json via CMake for accurate linting
---
 .github/workflows/lint-c.yml | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 .github/workflows/lint-c.yml

diff --git a/.github/workflows/lint-c.yml b/.github/workflows/lint-c.yml
new file mode 100644
index 0000000..24e837e
--- /dev/null
+++ b/.github/workflows/lint-c.yml
@@ -0,0 +1,27 @@
+name: C/C++ Lint
+
+on:
+  pull_request:
+    branches: [ "dev", "main" ]
+    paths:
+      - 'algorithm/**'
+
+jobs:
+  lint-c:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install clang-tools and cmake
+        run: sudo apt-get update && sudo apt-get install -y clang-format clang-tidy cmake
+
+      - name: Generate compile_commands.json
+        run: cmake -B ./algorithm/build -S ./algorithm
+
+      - name: Check C/C++ formatting (clang-format)
+        run: |
+          find ./algorithm -type f \( -name "*.c" -o -name "*.cpp" -o -name "*.h" \) | xargs clang-format --Werror --dry-run
+
+      - name: Run C/C++ linter (clang-tidy)
+        run: |
+          find ./algorithm/src ./algorithm/tests -type f \( -name "*.c" -o -name "*.cpp" \) | xargs clang-tidy -p ./algorithm/build
\ No newline at end of file

From 97e274b3be36ab151d580910e2eb28bb164234e0 Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:20:09 +0300
Subject: [PATCH 20/23] ci: configure Go and Python linting pipelines

---
 .github/workflows/lint-go.yml     | 22 ++++++++++++++++++++++
 .github/workflows/lint-python.yml | 21 +++++++++++++++++++++
 backend/go.mod                    |  2 +-
 3 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 .github/workflows/lint-go.yml
 create mode 100644 .github/workflows/lint-python.yml

diff --git a/.github/workflows/lint-go.yml b/.github/workflows/lint-go.yml
new file mode 100644
index 0000000..2008d26
--- /dev/null
+++ b/.github/workflows/lint-go.yml
@@ -0,0 +1,22 @@
+name: Go Lint
+
+on:
+  pull_request:
+    branches: [ "dev", "main" ]
+    paths:
+      - 'backend/**'
+
+jobs:
+  lint-go:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26'
+
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v6
+        with:
+          working-directory: ./backend
\ No newline at end of file
diff --git a/.github/workflows/lint-python.yml b/.github/workflows/lint-python.yml
new file mode 100644
index 0000000..aa32438
--- /dev/null
+++ b/.github/workflows/lint-python.yml
@@ -0,0 +1,21 @@
+name: Python Lint
+
+on:
+  pull_request:
+    branches: [ "dev", "main" ]
+    paths:
+      - 'parser/**'
+
+jobs:
+  lint-python:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Ruff
+        run: pip install ruff
+
+      - name: Run Ruff check and format
+        run: |
+          ruff check ./parser
+          ruff format --check ./parser
\ No newline at end of file
diff --git a/backend/go.mod b/backend/go.mod
index e20ddd8..f323727 100644
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -1,3 +1,3 @@
 module github.com/ilindan-dev/RAGDM/backend
 
-go 1.25.7
+go 1.26

From ee683efce6c5665900f8f41fd21c920449724ccb Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:33:44 +0300
Subject: [PATCH 21/23] ci: fix go version for linter and exclude build dir
 from clang-format

---
 .github/workflows/lint-c.yml  | 2 +-
 .github/workflows/lint-go.yml | 5 +++--
 backend/go.mod                | 2 +-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/lint-c.yml b/.github/workflows/lint-c.yml
index 24e837e..b07820e 100644
--- a/.github/workflows/lint-c.yml
+++ b/.github/workflows/lint-c.yml
@@ -20,7 +20,7 @@ jobs:
 
       - name: Check C/C++ formatting (clang-format)
         run: |
-          find ./algorithm -type f \( -name "*.c" -o -name "*.cpp" -o -name "*.h" \) | xargs clang-format --Werror --dry-run
+          find ./algorithm/src ./algorithm/include ./algorithm/tests -type f \( -name "*.c" -o -name "*.cpp" -o -name "*.h" \) | xargs clang-format --Werror --dry-run
 
       - name: Run C/C++ linter (clang-tidy)
         run: |
diff --git a/.github/workflows/lint-go.yml b/.github/workflows/lint-go.yml
index 2008d26..dad10c1 100644
--- a/.github/workflows/lint-go.yml
+++ b/.github/workflows/lint-go.yml
@@ -12,9 +12,10 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
-          go-version: '1.26'
+          go-version: '1.25'
+          check-latest: true
 
       - name: Run golangci-lint
         uses: golangci/golangci-lint-action@v6
diff --git a/backend/go.mod b/backend/go.mod
index f323727..86baf4d 100644
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -1,3 +1,3 @@
 module github.com/ilindan-dev/RAGDM/backend
 
-go 1.26
+go 1.25

From 378c4a325fb292b3ae4cf7cd8523bd27d1130310 Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:36:12 +0300
Subject: [PATCH 22/23] ci: fix go version for linter to 1.24

---
 .github/workflows/lint-go.yml | 2 +-
 backend/go.mod                | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/lint-go.yml b/.github/workflows/lint-go.yml
index dad10c1..f73415d 100644
--- a/.github/workflows/lint-go.yml
+++ b/.github/workflows/lint-go.yml
@@ -14,7 +14,7 @@ jobs:
 
       - uses: actions/setup-go@v6
         with:
-          go-version: '1.25'
+          go-version: '1.24'
           check-latest: true
 
       - name: Run golangci-lint
diff --git a/backend/go.mod b/backend/go.mod
index 86baf4d..50cf777 100644
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -1,3 +1,3 @@
 module github.com/ilindan-dev/RAGDM/backend
 
-go 1.25
+go 1.24

From 021d6c3ab1ba5555d738c476a78fbb2e1c858ea2 Mon Sep 17 00:00:00 2001
From: Gellert Ilya <gellertilya.job@gmail.com>
Date: Tue, 31 Mar 2026 19:39:34 +0300
Subject: [PATCH 23/23] ci: add test integration for C code

---
 .github/workflows/lint-c.yml | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/lint-c.yml b/.github/workflows/lint-c.yml
index b07820e..0141b62 100644
--- a/.github/workflows/lint-c.yml
+++ b/.github/workflows/lint-c.yml
@@ -1,4 +1,4 @@
-name: C/C++ Lint
+name: C/C++ CI
 
 on:
   pull_request:
@@ -7,7 +7,7 @@ on:
       - 'algorithm/**'
 
 jobs:
-  lint-c:
+  lint-and-test:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -15,7 +15,7 @@ jobs:
       - name: Install clang-tools and cmake
         run: sudo apt-get update && sudo apt-get install -y clang-format clang-tidy cmake
 
-      - name: Generate compile_commands.json
+      - name: Configure CMake and generate compile_commands.json
         run: cmake -B ./algorithm/build -S ./algorithm
 
       - name: Check C/C++ formatting (clang-format)
@@ -24,4 +24,11 @@ jobs:
 
       - name: Run C/C++ linter (clang-tidy)
         run: |
-          find ./algorithm/src ./algorithm/tests -type f \( -name "*.c" -o -name "*.cpp" \) | xargs clang-tidy -p ./algorithm/build
\ No newline at end of file
+          find ./algorithm/src ./algorithm/tests -type f \( -name "*.c" -o -name "*.cpp" \) | xargs clang-tidy -p ./algorithm/build
+
+      - name: Build C/C++ project
+        run: cmake --build ./algorithm/build
+
+      - name: Run tests (CTest)
+        working-directory: ./algorithm/build
+        run: ctest --output-on-failure
\ No newline at end of file