import yaml
import time
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

class DSLEngine:
    def __init__(self, driver):
        self.driver = driver
        self.wait = WebDriverWait(self.driver, 10)

    def _parse_locator(self, locator_str):
        """
        解析定位符字符串，例如 "id:username" -> (By.ID, "username")
        """
        if not locator_str:
            return None
        
        by_map = {
            "id": By.ID,
            "xpath": By.XPATH,
            "css": By.CSS_SELECTOR,
            "name": By.NAME,
            "class": By.CLASS_NAME,
            "tag": By.TAG_NAME
        }
        
        try:
            method, value = locator_str.split(":", 1)
            return by_map.get(method.lower()), value
        except ValueError:
            raise Exception(f"定位符格式错误: {locator_str}，应为 '类型:值'")

    def execute_step(self, step):
        """
        执行单个 DSL 步骤
        """
        action = step.get('action')
        locator_str = step.get('locator')
        value = step.get('value')
        desc = step.get('desc', '无描述')

        print(f"正在执行: [{action}] - {desc}")

        # 解析定位符 (如果有)
        locator = self._parse_locator(locator_str)

        # === 动作分发 (Action Dispatch) ===
        
        if action == "open":
            self.driver.get(value)

        elif action == "input":
            el = self.wait.until(EC.visibility_of_element_located(locator))
            el.clear()
            el.send_keys(str(value))

        elif action == "click":
            el = self.wait.until(EC.element_to_be_clickable(locator))
            el.click()

        elif action == "wait":
            time.sleep(float(value))

        elif action == "assert_text":
            el = self.wait.until(EC.visibility_of_element_located(locator))
            actual_text = el.text
            assert value in actual_text, f"断言失败: 期望 '{value}' 包含在 '{actual_text}' 中"
            print(f"  -> 断言通过: 发现 '{actual_text}'")

        else:
            raise Exception(f"未知的动作指令: {action}")

    def run_yaml(self, yaml_path):
        """
        加载并运行 YAML 文件
        """
        with open(yaml_path, 'r', encoding='utf-8') as f:
            data = yaml.safe_load(f)
        
        print(f"=== 开始测试: {data.get('name')} ===")
        
        for step in data.get('steps', []):
            try:
                self.execute_step(step)
            except Exception as e:
                print(f"  [X] 步骤执行失败: {e}")
                raise e # 抛出异常以终止测试
                
        print("=== 测试全部通过 ===")