import os
import pandas as pd

STATIC_PATH = './Static'

# 从文件夹中读取所有xlsx文件，每个文件对应一个label
# labelNames为label的名字，如果不提供则默认为文件名
def load_data(folder, labelNames, isDir):
  # 检查folder参数
  if folder is None:
    raise ValueError("The 'folder' parameter is required.")
    
  # 检查labelNames参数
  if labelNames is None:
    raise ValueError("The 'labelNames' parameter is required if 'folder' does not contain labels.")
    
  folder = os.path.join(STATIC_PATH, folder)
  
  # 看看有没有元数据文件夹  
  if not os.path.isdir(folder):
    raise ValueError(f"The folder '{folder}' does not exist.")

#   fileNames = [f for f in os.listdir(folder) if f.endswith('.xlsx')]
  
#   # 获取数据的最大行数
#   max_row_length = get_max_row_len(folder, fileNames)

#   all_features = []

#   for i, fileName in enumerate(fileNames):

#       features = load_xlsx(folder + '/' + fileName, labelNames[i], max_row_length, 'zero')
#       all_features.append(features)

#   data = pd.concat(all_features, ignore_index = True)

  data = None
  if not isDir:
    data = load_from_file(folder=folder, labelNames=labelNames)
  else:
    data = load_from_folder(folder=folder, labelNames=labelNames)
  print(data)
  return data

def load_from_folder(folder, labelNames):
    pass

def load_from_file(folder, labelNames):
  fileNames = [labelName + ".xlsx" for labelName in labelNames]
  # 获取数据的最大行数
  max_row_length = get_max_row_len(folder, fileNames)
  all_features = []
  for i, fileName in enumerate(fileNames):
      features = load_xlsx(folder + '/' + fileName, labelNames[i], max_row_length, 'zero')
      all_features.append(features)
  return pd.concat(all_features, ignore_index = True)


def load_xlsx(fileName, labelName, max_row_length = 1000, fill_rule = None):
    df = pd.read_excel(fileName)

    # 提取偶数列
    features = df.iloc[0:, 1::2]
    features.dropna(inplace=True)  
    features.reset_index(drop=True, inplace=True)

    features = features.T

     # 补全每一行到指定长度
    features = features.apply(lambda row: fill_to_len(row, max_row_length, fill_rule), axis=1)
    
    features['label'] = labelName
    features.columns = [f'feature{i+1}' for i in range(max_row_length)] + ['label']
    
    return features
    
def fill_to_len(row, length = 1000, rule = None):
    fill_value = 0

    if rule == 'min':
        fill_value = row.min()
    elif rule == 'mean':
        fill_value = row.mean()
    elif rule == 'zero':
        fill_value = 0
    fill_values = pd.Series([fill_value] * (length - len(row)))

    return pd.concat([row, fill_values], ignore_index=True)

def get_max_row_len(folder, filenames):
    max_len = 0
    for filename in filenames:
        df = pd.read_excel(os.path.join(folder, filename))
        max_len = max(max_len, df.shape[0])
    return max_len

__all__ = ['load_data']