/**
 * @file tests/unit/test_process.cpp
 * @brief Test src/process.* functions.
 */
// test imports
#include "../tests_common.h"

// standard imports
#include <filesystem>
#include <fstream>

// local imports
#include <src/process.h>

namespace fs = std::filesystem;

class ProcessPNGTest: public ::testing::Test {
protected:
  void SetUp() override {
    // Create test directory
    test_dir = fs::temp_directory_path() / "sunshine_process_png_test";
    fs::create_directories(test_dir);
  }

  void TearDown() override {
    // Clean up test directory
    if (fs::exists(test_dir)) {
      fs::remove_all(test_dir);
    }
  }

  // Helper function to create a file with specific content
  void createTestFile(const fs::path &path, const std::vector<unsigned char> &content) const {
    std::ofstream file(path, std::ios::binary);
    file.write(reinterpret_cast<const char *>(content.data()), content.size());
    file.close();
  }

  fs::path test_dir;
};

// Tests for check_valid_png function
TEST_F(ProcessPNGTest, CheckValidPNG_ValidSignature) {
  // Valid PNG signature
  const std::vector<unsigned char> valid_png_data = {
    0x89,
    0x50,
    0x4E,
    0x47,
    0x0D,
    0x0A,
    0x1A,
    0x0A,  // PNG signature
    // Add some dummy data to make it more realistic
    0x00,
    0x00,
    0x00,
    0x0D,
    0x49,
    0x48,
    0x44,
    0x52
  };

  const fs::path test_file = test_dir / "valid.png";
  createTestFile(test_file, valid_png_data);

  EXPECT_TRUE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_WrongSignature) {
  // Invalid PNG signature (wrong magic bytes)
  const std::vector<unsigned char> invalid_png_data = {
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00
  };

  const fs::path test_file = test_dir / "invalid.png";
  createTestFile(test_file, invalid_png_data);

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_TooShort) {
  // File too short (less than 8 bytes)
  const std::vector<unsigned char> short_data = {
    0x89,
    0x50,
    0x4E,
    0x47
  };

  const fs::path test_file = test_dir / "short.png";
  createTestFile(test_file, short_data);

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_EmptyFile) {
  // Empty file
  const std::vector<unsigned char> empty_data = {};

  const fs::path test_file = test_dir / "empty.png";
  createTestFile(test_file, empty_data);

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_NonExistentFile) {
  // File doesn't exist
  const fs::path test_file = test_dir / "nonexistent.png";

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_RealFile) {
  // Test with the actual sunshine.png from the project root

  // Only run this test if the file exists
  if (const fs::path sunshine_png = fs::path(SUNSHINE_SOURCE_DIR) / "sunshine.png"; fs::exists(sunshine_png)) {
    EXPECT_TRUE(proc::check_valid_png(sunshine_png));
  } else {
    GTEST_SKIP() << "sunshine.png not found in project root";
  }
}

TEST_F(ProcessPNGTest, CheckValidPNG_JPEGFile) {
  // JPEG signature (not PNG)
  const std::vector<unsigned char> jpeg_data = {
    0xFF,
    0xD8,
    0xFF,
    0xE0,
    0x00,
    0x10,
    0x4A,
    0x46
  };

  const fs::path test_file = test_dir / "fake.png";
  createTestFile(test_file, jpeg_data);

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

TEST_F(ProcessPNGTest, CheckValidPNG_PartialSignature) {
  // Partial PNG signature (first 4 bytes correct, rest wrong)
  const std::vector<unsigned char> partial_png_data = {
    0x89,
    0x50,
    0x4E,
    0x47,
    0x00,
    0x00,
    0x00,
    0x00
  };

  const fs::path test_file = test_dir / "partial.png";
  createTestFile(test_file, partial_png_data);

  EXPECT_FALSE(proc::check_valid_png(test_file));
}

// Tests for validate_app_image_path function
TEST_F(ProcessPNGTest, ValidateAppImagePath_EmptyPath) {
  // Empty path should return default
  const std::string result = proc::validate_app_image_path("");
  EXPECT_EQ(result, DEFAULT_APP_IMAGE_PATH);
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_NonPNGExtension) {
  // Non-PNG extension should return default
  const std::string result = proc::validate_app_image_path("image.jpg");
  EXPECT_EQ(result, DEFAULT_APP_IMAGE_PATH);
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_CaseInsensitiveExtension) {
  // Test that .PNG (uppercase) is recognized
  // Create a valid PNG file
  const std::vector<unsigned char> valid_png_data = {
    0x89,
    0x50,
    0x4E,
    0x47,
    0x0D,
    0x0A,
    0x1A,
    0x0A,
    0x00,
    0x00,
    0x00,
    0x0D,
    0x49,
    0x48,
    0x44,
    0x52
  };

  const fs::path test_file = test_dir / "test.PNG";
  createTestFile(test_file, valid_png_data);

  const std::string result = proc::validate_app_image_path(test_file.string());
  // Should accept uppercase .PNG extension
  EXPECT_NE(result, DEFAULT_APP_IMAGE_PATH);
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_NonExistentFile) {
  // Non-existent PNG file should return default
  const std::string result = proc::validate_app_image_path("/nonexistent/path/image.png");
  EXPECT_EQ(result, DEFAULT_APP_IMAGE_PATH);
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_InvalidPNGSignature) {
  // File with .png extension but invalid signature should return default
  const std::vector<unsigned char> invalid_data = {
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00,
    0x00
  };

  const fs::path test_file = test_dir / "invalid.png";
  createTestFile(test_file, invalid_data);

  const std::string result = proc::validate_app_image_path(test_file.string());
  EXPECT_EQ(result, DEFAULT_APP_IMAGE_PATH);
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_ValidPNG) {
  // Valid PNG file should return the path
  const std::vector<unsigned char> valid_png_data = {
    0x89,
    0x50,
    0x4E,
    0x47,
    0x0D,
    0x0A,
    0x1A,
    0x0A,
    0x00,
    0x00,
    0x00,
    0x0D,
    0x49,
    0x48,
    0x44,
    0x52
  };

  const fs::path test_file = test_dir / "valid.png";
  createTestFile(test_file, valid_png_data);

  const std::string result = proc::validate_app_image_path(test_file.string());
  EXPECT_EQ(result, test_file.string());
}

TEST_F(ProcessPNGTest, ValidateAppImagePath_OldSteamDefault) {
  // Test the special case for old steam image path
  const std::string result = proc::validate_app_image_path("./assets/steam.png");
  EXPECT_EQ(result, SUNSHINE_ASSETS_DIR "/steam.png");
}