test(spectool): Add end-to-end test for analysis tool

Adds a new CTest unit test that performs a full, end-to-end verification of the 'spectool analyze' command.

The test programmatically generates a sine wave, saves it as a .wav file, executes the spectool executable as a subprocess to analyze the wave, and then verifies the integrity of the resulting .spec file.

This ensures the analysis pipeline (WAV decoding, windowing, FDCT, and file I/O) works correctly.

1 files changed, 91 insertions, 0 deletions

diff --git a/src/tests/test_spectool.cpp b/src/tests/test_spectool.cpp
new file mode 100644
index 0000000..ae64cc3
--- /dev/null
+++ b/src/tests/test_spectool.cpp
@@ -0,0 +1,91 @@
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h> // For system()
+#include <vector>
+#include <math.h>
+#include "miniaudio.h"
+#include "audio/dct.h" // For DCT_SIZE
+
+// Re-defining the header here to avoid dependency on the tool's source
+struct SpecHeader {
+    char magic[4];
+    int32_t version;
+    int32_t dct_size;
+    int32_t num_frames;
+};
+
+#define TEST_SAMPLE_RATE 32000
+#define TEST_DURATION_SECONDS 1
+#define TEST_FREQ 440.0f
+#define PI 3.14159265f
+
+int main() {
+    printf("Running spectool end-to-end test...\n");
+
+    const char* wav_path = "test_signal.wav";
+    const char* spec_path = "test_signal.spec";
+    const char* spectool_path = "./spectool"; // Assumes ctest is run from `build` dir
+
+    // 1. Generate and save a WAV file
+    ma_encoder_config enc_config = ma_encoder_config_init(ma_encoding_format_wav, ma_format_f32, 1, TEST_SAMPLE_RATE);
+    ma_encoder encoder;
+    if (ma_encoder_init_file(wav_path, &enc_config, &encoder) != MA_SUCCESS) {
+        printf("TEST FAILED: Could not initialize WAV encoder.\n");
+        return 1;
+    }
+
+    std::vector<float> pcm_data(TEST_SAMPLE_RATE * TEST_DURATION_SECONDS);
+    for (size_t i = 0; i < pcm_data.size(); ++i) {
+        pcm_data[i] = 0.5f * sinf(2.0f * PI * TEST_FREQ * i / TEST_SAMPLE_RATE);
+    }
+    ma_uint64 frames_written;
+    ma_encoder_write_pcm_frames(&encoder, pcm_data.data(), pcm_data.size(), &frames_written);
+    ma_encoder_uninit(&encoder);
+    printf("  Generated %s\n", wav_path);
+
+    // 2. Run spectool analyze
+    char command[512];
+    snprintf(command, sizeof(command), "%s analyze %s %s", spectool_path, wav_path, spec_path);
+    printf("  Executing: %s\n", command);
+    int return_code = system(command);
+    assert(return_code == 0);
+    printf("  spectool executed successfully.\n");
+
+    // 3. Verify the output .spec file
+    FILE* f_spec = fopen(spec_path, "rb");
+    assert(f_spec != NULL);
+    
+    SpecHeader header;
+    fread(&header, sizeof(SpecHeader), 1, f_spec);
+    assert(strncmp(header.magic, "SPEC", 4) == 0);
+    assert(header.version == 1);
+    assert(header.dct_size == DCT_SIZE);
+    
+    int expected_frames = (TEST_SAMPLE_RATE * TEST_DURATION_SECONDS) / DCT_SIZE;
+    if ((TEST_SAMPLE_RATE * TEST_DURATION_SECONDS) % DCT_SIZE != 0) {
+        expected_frames++;
+    }
+    assert(header.num_frames == expected_frames);
+
+    printf("  .spec header verified.\n");
+    
+    // Just check that we have some non-zero data
+    std::vector<float> spec_data(header.num_frames * header.dct_size);
+    fread(spec_data.data(), sizeof(float), spec_data.size(), f_spec);
+    fclose(f_spec);
+
+    double total_energy = 0.0;
+    for(float val : spec_data) {
+        total_energy += fabs(val);
+    }
+    assert(total_energy > 0.0);
+    printf("  .spec data seems valid.\n");
+
+    // 4. Cleanup
+    remove(wav_path);
+    remove(spec_path);
+    printf("  Cleaned up temporary files.\n");
+
+    printf("...spectool test PASSED!\n");
+    return 0;
+}