import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).parent.parent / 'src'))

from gdiffer.language_detector import detect_language


class TestLanguageDetector:
    def test_detect_python_extension(self, language_detector):
        assert language_detector.detect_from_filename("test.py") == "python"
        assert language_detector.detect_from_filename("script.pyw") == "python"
        assert language_detector.detect_from_filename("module.pyx") == "python"

    def test_detect_javascript_extension(self, language_detector):
        assert language_detector.detect_from_filename("app.js") == "javascript"
        assert language_detector.detect_from_filename("module.mjs") == "javascript"
        assert language_detector.detect_from_filename("component.cjs") == "javascript"
        assert language_detector.detect_from_filename("file.jsx") == "javascript"

    def test_detect_typescript_extension(self, language_detector):
        assert language_detector.detect_from_filename("app.ts") == "typescript"
        assert language_detector.detect_from_filename("component.tsx") == "typescript"
        assert language_detector.detect_from_filename("module.mts") == "typescript"

    def test_detect_java_extension(self, language_detector):
        assert language_detector.detect_from_filename("Main.java") == "java"

    def test_detect_go_extension(self, language_detector):
        assert language_detector.detect_from_filename("main.go") == "go"

    def test_detect_rust_extension(self, language_detector):
        assert language_detector.detect_from_filename("lib.rs") == "rust"

    def test_detect_c_extensions(self, language_detector):
        assert language_detector.detect_from_filename("file.c") == "c"
        assert language_detector.detect_from_filename("header.h") == "c"
        assert language_detector.detect_from_filename("source.cpp") == "cpp"
        assert language_detector.detect_from_filename("file.cc") == "cpp"
        assert language_detector.detect_from_filename("header.hpp") == "cpp"

    def test_detect_ruby_extension(self, language_detector):
        assert language_detector.detect_from_filename("script.rb") == "ruby"
        assert language_detector.detect_from_filename("template.erb") == "ruby"

    def test_detect_php_extension(self, language_detector):
        assert language_detector.detect_from_filename("index.php") == "php"

    def test_detect_unknown_extension(self, language_detector):
        assert language_detector.detect_from_filename("file.xyz") is None
        assert language_detector.detect_from_filename("README") is None

    def test_detect_from_content_python(self, language_detector):
        code = """def hello():
    return "Hello, World!"

if __name__ == "__main__":
    hello()
"""
        assert language_detector.detect_from_content(code) == "python"

    def test_detect_from_content_javascript(self, language_detector):
        code = """function greet(name) {
    return "Hello, " + name;
}

const result = greet("World");
"""
        assert language_detector.detect_from_content(code) == "javascript"

    def test_detect_from_content_rust(self, language_detector):
        code = """fn main() {
    println!("Hello, World!");
}

fn add(a: i32, b: i32) -> i32 {
    a + b
}
"""
        assert language_detector.detect_from_content(code) == "rust"

    def test_detect_from_content_go(self, language_detector):
        code = """package main

import "fmt"

func main() {
    fmt.Println("Hello")
}
"""
        assert language_detector.detect_from_content(code) == "go"

    def test_detect_combined_filename_content(self, language_detector):
        result = language_detector.detect("test.py", "def hello(): pass")
        assert result == "python"

    def test_detect_script_without_extension(self, language_detector):
        result = language_detector.detect("Makefile", "all:\n\techo hello")
        assert result == "text"

    def test_get_supported_languages(self, language_detector):
        languages = language_detector.get_supported_languages()
        assert isinstance(languages, list)
        assert "python" in languages
        assert "javascript" in languages
        assert "java" in languages

    def test_is_language_supported(self, language_detector):
        assert language_detector.is_language_supported("python")
        assert language_detector.is_language_supported("javascript")
        assert not language_detector.is_language_supported("brainfuck")


class TestDetectLanguageFunction:
    def test_detect_language_python(self):
        result = detect_language("script.py", "def test(): pass")
        assert result == "python"

    def test_detect_language_unknown(self):
        result = detect_language("file.xyz", "")
        assert result == "text" or result is None

    def test_detect_language_from_filename_only(self):
        result = detect_language("main.java")
        assert result == "java"