<?php

namespace TypePhp\Tests\Backend;

use PHPUnit\Framework\TestCase;
use TypePhp\Platform\Windows;
use TypePhp\Platform\Linux;
use TypePhp\Backend\Msvc;
use TypePhp\Backend\Gcc;
use TypePhp\Backend\Clang;
use TypePhp\Backend\CompilerFactory;
use TypePhp\CompilerTest;
use TypePhp\Exception\TestError;

class BackendTest extends TestCase
{
    private array $temporaryDirectories = [];

    protected function tearDown(): void
    {
        parent::tearDown();
        foreach ($this->temporaryDirectories as $dir) {
            $this->removeDirectory($dir);
        }
        $this->temporaryDirectories = [];
    }

    private function createTemporaryDirectory(string $prefix): string
    {
        $dir = sys_get_temp_dir() . '/' . $prefix . '_' . uniqid();
        mkdir($dir, 0777, true);
        $this->temporaryDirectories[] = $dir;
        return $dir;
    }

    private function removeDirectory(string $dir): void
    {
        if (!is_dir($dir)) {
            return;
        }

        $files = array_diff(scandir($dir), ['.', '..']);
        foreach ($files as $file) {
            $path = $dir . DIRECTORY_SEPARATOR . $file;
            is_dir($path) ? $this->removeDirectory($path) : unlink($path);
        }
        rmdir($dir);
    }

    /**
     * 测试 MSVC 编译器基本信息
     */
    public function testMsvcBasic(): void
    {
        $platform = new Windows();
        $compiler = new Msvc($platform);
        
        $this->assertEquals('MSVC', $compiler->getName());
        $this->assertEquals('cl', $compiler->getCompilerCommand());
        $this->assertEquals('link', $compiler->getLinkerCommand());
    }

    /**
     * 测试 MSVC 完整编译命令
     */
    public function testMsvcBuildCompileCommand(): void
    {
        $platform = new Windows([], true); // ZTS mode
        $compiler = new Msvc($platform);
        
        $cmd = $compiler->buildCompileCommand(
            'test.cpp',
            'test.obj',
            [
                'optimize' => 2,
                'cpp_std' => 'c++17',
            ]
        );
        
        $this->assertStringContainsString('cl', $cmd);
        $this->assertStringContainsString('/c', $cmd);
        $this->assertStringContainsString('/DZEND_WIN32', $cmd);
        $this->assertStringContainsString('/DPHP_WIN32', $cmd);
        $this->assertStringContainsString('/DZTS', $cmd); // ZTS enabled
        $this->assertStringContainsString('/O2', $cmd);
        $this->assertStringContainsString('/W3', $cmd);
        $this->assertStringContainsString('/std:c++17', $cmd);
        $this->assertStringContainsString('/EHsc', $cmd);
        $this->assertStringContainsString('/MD', $cmd);
        $this->assertStringContainsString('/nologo', $cmd);
    }

    public function testMsvcBuildCCompileCommandKeepsSharedCompilerOptions(): void
    {
        $platform = new Windows([], true);
        $compiler = new Msvc($platform);

        $cmd = $compiler->buildCCompileCommand('misc.c', 'misc.obj', [
            'sanitize' => 'address',
            'enable_profiler' => true,
            'prof_output' => 'app.prof',
            'user_defines' => ['FEATURE_X=1'],
            'lto' => true,
            'is_zts' => true,
            'cflags' => '/experimental:c11atomics',
        ]);

        $this->assertStringContainsString('/TC', $cmd);
        $this->assertStringContainsString('/fsanitize=address', $cmd);
        $this->assertStringContainsString('/DPPROF_ON=1', $cmd);
        $this->assertStringContainsString('/D' . escapeshellarg('PROF_OUTPUT_FILE="app.prof"'), $cmd);
        $this->assertStringContainsString('/DFEATURE_X=1', $cmd);
        $this->assertStringContainsString('/GL', $cmd);
        $this->assertStringContainsString('/DZTS', $cmd);
        $this->assertStringContainsString('/experimental:c11atomics', $cmd);
        $this->assertStringNotContainsString('/EHsc', $cmd);
        $this->assertStringNotContainsString('/std:', $cmd);
    }

    public function testMsvcLargeObjectFormatAppliesToGeneratedAndNativeCommands(): void
    {
        $compiler = new Msvc(new Windows());
        foreach ([false, true] as $debug) {
            $options = ['debug' => $debug];
            $this->assertStringContainsString('/bigobj', $compiler->buildCompileCommand('generated.cc', 'generated.obj', $options));
            $this->assertStringContainsString('/bigobj', $compiler->buildNativeCompileCommand('native.c', 'native.obj', $options, 'c'));
        }
        $this->assertStringNotContainsString('/bigobj', $compiler->buildLinkOptions());
    }

    public function testMsvcDebugPdbOptionsApplyToCppAndCCommands(): void
    {
        $compiler = new Msvc(new Windows());
        $pdb = 'C:\\build output\\cache\\msvc\\app.compile.pdb';
        $options = ['debug' => true, 'compiler_pdb' => $pdb];

        $cpp = $compiler->buildCompileCommand('app.cpp', 'app.obj', $options);
        $c = $compiler->buildCCompileCommand('helper.c', 'helper.obj', $options);

        foreach ([$cpp, $c] as $command) {
            $this->assertStringContainsString('/Fd' . escapeshellarg($pdb), $command);
            $this->assertStringContainsString('/FS', $command);
        }
    }

    /**
     * 测试 MSVC 完整链接命令
     */
    public function testMsvcBuildLinkCommand(): void
    {
        $platform = new Windows();
        $compiler = new Msvc($platform);
        
        $cmd = $compiler->buildLinkCommand(
            ['test.obj'],
            'output.exe',
            [
                'debug' => true,
                'no_console' => false,
            ]
        );
        
        $this->assertStringContainsString('link', $cmd);
        $this->assertStringContainsString('/OUT:', $cmd);
        $this->assertStringContainsString('/DEBUG', $cmd);
        $this->assertStringContainsString('/PDB:' . escapeshellarg('output.pdb'), $cmd);
        $this->assertStringContainsString('/NODEFAULTLIB:LIBCMT', $cmd);
        $this->assertStringContainsString('/nologo', $cmd);
        $compiler->cleanupResponseFile();
    }

    public function testMsvcDebugLinkPdbFollowsOutputPath(): void
    {
        $compiler = new Msvc(new Windows());
        $output = 'C:\\build output\\app.dll';

        $cmd = $compiler->buildLinkCommand(['app.obj'], $output, ['debug' => true]);

        $this->assertStringContainsString(
            '/PDB:' . escapeshellarg('C:\\build output\\app.pdb'),
            $cmd
        );
        $compiler->cleanupResponseFile();
    }

    /**
     * 测试 GCC 编译器基本信息
     */
    public function testGccBasic(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform);
        
        $this->assertEquals('GCC', $compiler->getName());
        $this->assertEquals('g++', $compiler->getCompilerCommand());
        $this->assertEquals('g++', $compiler->getLinkerCommand());
    }

    public function testGccBuildCompileCommandUsesCustomCompilerAndIncludes(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform, '/opt/toolchain/bin/g++');

        $cmd = $compiler->buildCompileCommand('test.cpp', 'test.o', [
            'include_paths' => ['/usr/include/php'],
            'cpp_std' => 'c++20',
            'cxxflags' => '-fno-rtti',
        ]);

        $this->assertStringStartsWith('/opt/toolchain/bin/g++', $cmd);
        $this->assertStringContainsString('-I' . escapeshellarg('/usr/include/php'), $cmd);
        $this->assertStringContainsString('-std=c++20', $cmd);
        $this->assertStringContainsString('-fno-rtti', $cmd);
    }

    public function testGccOnWindowsUsesGccIncludeSyntaxForAllSourceTypes(): void
    {
        $compiler = new Gcc(new Windows());
        $includePaths = ['C:\\phpx\\include', 'C:\\Program Files\\PHP\\include'];
        $options = [
            'include_paths' => $includePaths,
        ];
        $commands = [
            $compiler->buildCompileCommand('test.cpp', 'test.obj', $options),
            $compiler->buildCCompileCommand('test.c', 'test.obj', $options),
            $compiler->buildNativeCompileCommand('test.S', 'test.obj', $options, 'assembler'),
        ];

        foreach ($commands as $cmd) {
            foreach ($includePaths as $path) {
                $this->assertStringContainsString('-I' . escapeshellarg($path), $cmd);
            }
            $this->assertStringNotContainsString('/I ', $cmd);
        }
    }

    public function testGccBuildCCompileCommandKeepsSharedCompilerOptions(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform);

        $cmd = $compiler->buildCCompileCommand('misc.c', 'misc.o', [
            'sanitize' => 'address',
            'enable_profiler' => true,
            'prof_output' => 'app.prof',
            'user_defines' => ['FEATURE_X=1'],
            'lto' => true,
            'march' => 'native',
            'target_platform' => 'aarch64-linux-gnu',
            'build_mode' => 'ext',
            'cflags' => '-ffreestanding -fno-builtin',
        ]);

        $this->assertStringContainsString('-fsanitize=address', $cmd);
        $this->assertStringContainsString('-DPPROF_ON=1', $cmd);
        $this->assertStringContainsString('-D' . escapeshellarg('PROF_OUTPUT_FILE="app.prof"'), $cmd);
        $this->assertStringContainsString('-DFEATURE_X=1', $cmd);
        $this->assertStringContainsString('-flto', $cmd);
        $this->assertStringContainsString('-march=native', $cmd);
        $this->assertStringContainsString('--target=aarch64-linux-gnu', $cmd);
        $this->assertStringContainsString('-fPIC', $cmd);
        $this->assertStringContainsString('-ffreestanding -fno-builtin', $cmd);
    }

    public function testGccBuildAssemblerCommandUsesNativeFlags(): void
    {
        $compiler = new Gcc(new Linux());

        $cmd = $compiler->buildNativeCompileCommand('entry.S', 'entry.o', [
            'nativeflags' => '-m64 -mno-red-zone',
        ], 'assembler');

        $this->assertStringContainsString('-x assembler', $cmd);
        $this->assertStringContainsString('-m64 -mno-red-zone', $cmd);
    }

    public function testGccBuildLinkCommandIncludesPlatformPathsOptionsAndLibraries(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform, 'g++');

        $cmd = $compiler->buildLinkCommand(['a.o', 'b.o'], 'app', [
            'library_paths' => ['/usr/lib'],
            'libraries' => ['/usr/lib/libphpx.so', 'php'],
            'ldflags' => '-Wl,--as-needed',
            'build_mode' => 'ext',
        ]);

        $this->assertStringStartsWith('g++', $cmd);
        $this->assertStringContainsString('-L' . escapeshellarg('/usr/lib'), $cmd);
        $this->assertStringContainsString('-Wl,--as-needed', $cmd);
        $this->assertStringContainsString('-shared', $cmd);
        $this->assertStringContainsString('-lphpx', $cmd);
        $this->assertStringContainsString('-lphp', $cmd);
        $compiler->cleanupResponseFile();
    }

    public function testBuildCleansResponseFileWhenLinkFails(): void
    {
        $dir = $this->createTemporaryDirectory('backend_link_failure');
        $target = $dir . '/app';
        $backend = new Gcc(new Linux(), 'false');
        $compiler = new class(TYPEPHP_ROOT_PATH, $target, $backend) extends CompilerTest {
            public function __construct(
                string $rootPath,
                private readonly string $testTarget,
                \TypePhp\Backend\CompilerBackend $backend
            ) {
                parent::__construct($rootPath);
                $this->forTest = true;
                $this->compilerBackend = $backend;
            }

            protected function getTargetFileName(): string
            {
                return $this->testTarget;
            }
        };

        // getLibraries() 必须先找到 phpx 库才能走到链接失败路径。
        // 用临时目录提供静态库占位文件，使测试不依赖本机是否已构建 phpx。
        $phpxHome = $dir . '/phpx';
        mkdir($phpxHome . '/lib', 0777, true);
        touch($phpxHome . '/lib/libphpx.a');
        $previousPhpxHome = getenv('PHPX_HOME');
        putenv('PHPX_HOME=' . $phpxHome);

        try {
            $compiler->build([$dir . '/missing.o']);
            $this->fail('The failing linker command should abort the build');
        } catch (TestError $e) {
            $this->assertStringContainsString('link failed', $e->getMessage());
        } finally {
            if ($previousPhpxHome === false) {
                putenv('PHPX_HOME');
            } else {
                putenv('PHPX_HOME=' . $previousPhpxHome);
            }
        }

        $this->assertFileDoesNotExist($target . '.rsp');
    }

    public function testResponseFileArgumentIsEscapedForPathsWithSpaces(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform, 'g++');
        $dir = $this->createTemporaryDirectory('backend link path');
        $target = $dir . '/my app';
        $rspFile = $target . '.rsp';
        $objectWithSpace = $dir . '/object one.o';
        $objectWithoutSpace = $dir . '/object_two.o';

        $cmd = $compiler->buildLinkCommand([$objectWithSpace, $objectWithoutSpace], $target);

        $this->assertStringContainsString(escapeshellarg('@' . $rspFile), $cmd);
        $this->assertStringContainsString('-o ' . escapeshellarg($target), $cmd);
        $this->assertFileExists($rspFile);

        $lines = file($rspFile, FILE_IGNORE_NEW_LINES);
        $this->assertSame('"' . $objectWithSpace . '"', $lines[0]);
        $this->assertSame('"' . $objectWithoutSpace . '"', $lines[1]);
    }

    public function testResponseFileCanBePlacedInTheBuildDirectory(): void
    {
        $platform = new Linux();
        $compiler = new Gcc($platform, 'g++');
        $dir = $this->createTemporaryDirectory('backend response build directory');
        $target = $dir . '/output/my app';
        $rspFile = $dir . '/build/my app.rsp';
        $object = $dir . '/object.o';

        $cmd = $compiler->buildLinkCommand(
            [$object],
            $target,
            ['response_file' => $rspFile],
        );

        $this->assertStringContainsString(escapeshellarg('@' . $rspFile), $cmd);
        $this->assertFileExists($rspFile);
        $this->assertFileDoesNotExist($target . '.rsp');
    }

    /**
     * 测试 Clang 编译器基本信息
     */
    public function testClangBasic(): void
    {
        $platform = new Linux();
        $compiler = new Clang($platform);
        
        $this->assertEquals('Clang', $compiler->getName());
        $this->assertEquals('clang++', $compiler->getCompilerCommand());
        $this->assertEquals('clang++', $compiler->getLinkerCommand());
    }

    /**
     * 测试 Clang Windows 平台链接器
     */
    public function testClangWindowsLinker(): void
    {
        $platform = new Windows();
        $compiler = new Clang($platform);
        
        // Windows 下 Clang 使用 link.exe
        $this->assertEquals('link', $compiler->getLinkerCommand());
    }

    public function testCompilerFactoryKeepsConfiguredCompilerCommand(): void
    {
        $compiler = CompilerFactory::createByName('/opt/llvm/bin/clang++', new Linux());

        $this->assertInstanceOf(Clang::class, $compiler);
        $this->assertSame('/opt/llvm/bin/clang++', $compiler->getCompilerCommand());
        $this->assertSame('/opt/llvm/bin/clang++', $compiler->getLinkerCommand());
    }

}