""" 
----------------------------------------
Directory Tree Generator
----------------------------------------
This project is useful for visualizing the 
relationship between files and directories 
and making their positioning easy to comprehend. 
Python OS library can be used to list the 
files and directories within a specific directory. 
The excellent frameworks of this project are Docopt 
and Argparse. 
----------------------------------------
Library to import for the project:
    `pip install walkdir`
----------------------------------------
"""

import argparse
import os
from walkdir import filtered_walk

parser = argparse.ArgumentParser(description='Print the directory-tree code for the LaTeX dirtree package.')
parser.add_argument(dest='path', type=str, help="Root directory of the tree")
parser.add_argument('-d', '--maxDepth', dest='maxDepth', type=int, help="Max depth for tree expansion")
parser.add_argument('-H', '--includeHidden', dest='includeHidden', action='store_true', help='Include hidden files')
parser.add_argument('-S', '--includeSystem', dest='includeSystem', action='store_true', help='Include system files')
system_file_names = [".DS_Store"]

# Delete trailing / in rootDir which can lead to errors
def delete_trailing_slash(path_name):
    while path_name.endswith('/'):
        path_name = path_name[:-1]
    return path_name

# Count how many levels deep is the directory with respect to dirRoot
def get_relative_depth(dir_path, level_offset):
    return dir_path.count(os.path.sep) - level_offset

# Escape illegal symbols for LaTeX
def escape_illegal(name):
    illegal_char_array = ['\\', '&', '%', '$', '#', '_', '{', '}', '~', '^']
    for char in illegal_char_array:
        name = name.replace(char, "\\" + char)
    return name
rootDir = delete_trailing_slash(parser.parse_args().path)
includeHidden = parser.parse_args().includeHidden
includeSystem = parser.parse_args().includeSystem
maxDepth = parser.parse_args().maxDepth

# if the directory exists
if os.path.isdir(rootDir) and os.path.exists(rootDir):
    indentChar = " "

    # Depth of the root (i.e. number of "/")
    levelOffset = rootDir.count(os.path.sep) - 1

    # Create filter
    excluded_filter = []
    if not includeHidden:
        excluded_filter.append(".*")
    if not includeSystem:
        excluded_filter += system_file_names
    print ("\dirtree{%")
    for dirName, subdirList, fileList in sorted(filtered_walk(rootDir, depth=maxDepth, excluded_dirs=excluded_filter,
        excluded_files=excluded_filter)):
        level = get_relative_depth(dirName, levelOffset)
        baseName = os.path.basename(dirName)
        if level == 1:  # for the first level only print the whole path
            print(indentChar + "." + str(level) + " {" + escape_illegal(dirName) + "} .")
        else:
            print(indentChar * level + "." + str(level) + " {" + escape_illegal((os.path.basename(dirName))) + "} .")
        level += 1
        for fileName in sorted(fileList):
            print(indentChar * level + "." + str(level) + " {" + escape_illegal(fileName) + "} .")
    print ("}")
else:
    print ("Error: root directory not found")