from flask import Flask, render_template, request
from sympy import symbols, Eq, solve

app = Flask(__name__)


@app.route('/', methods=['GET', 'POST'])
def index():
  solutions = []
  error = None  # 初始化错误消息
  if request.method == 'POST':
    equation = request.form['equation']
    result = solve_equation_helper(equation)
    if 'error' in result:  # 如果返回的是错误消息字典
      error = result['error']  # 设置错误消息
    else:
      solutions = result  # 设置解方程结果
  return render_template('yyfc.html', solutions=solutions,
                         error=error)  # 传入错误消息参数


def solve_equation_helper(equation):
  try:
    # 将等式按等号分割成左右两部分
    left, right = equation.split('=')

    # 创建符号变量
    x = symbols('x')

    # 创建方程
    eq = Eq(eval(left), eval(right))

    # 求解方程
    solutions = solve(eq, x)

    return solutions
  except Exception:
    error_message = "请确保未知数为x，并且输入正确，其中*表示乘号，**表示乘方，/表示分式。如果还有问题，请把错误提示和发生错误的时间报告给星空暗夜团队。"
    return {'error': error_message}  # 返回带有错误消息的字典


if __name__ == '__main__':
  app.run(host='0.0.0.0', port=7860)