import os
from datetime import datetime
from flask import current_app as app
try:
    from urllib.request import pathname2url
except ImportError:
    from urllib import pathname2url

def file_date_human(num):
    return datetime.fromtimestamp(
        num
    ).strftime(app.config['DATE_FORMAT'])


def file_stat(path, filename):
    full_path = os.path.join(path, filename)
    s = os.stat(full_path)
    return {
        'size': file_size_MB(s.st_size),
        'mtime': file_date_human(s.st_mtime),
        'name': filename,
        'url': path2url(filename)
    }


def file_size_human(num,HTML=True):
    space = ' ' if HTML else ' '
    for x in [space + 'B', 'KB', 'MB', 'GB', 'TB']:
        if num < 1024.0:
            if x == space + 'B':
                return "%d%s%s" % (num, space, x)
            return "%3.1f%s%s" % (num, space, x)
        num /= 1024.0


def file_size_MB(num):
    return "{:,.2f}".format(num/(1024*1024))


def get_folder_size(path):
    total_size = 0
    for dirpath, dirnames, filenames in os.walk(path):
        for f in filenames:
            fp = os.path.join(dirpath, f)
            total_size += os.path.getsize(fp)
    return total_size


def get_or_none(key,d,none = None):
    if key in d:
        return d[key]
    else:
        return none


def is_path_safe(path):
    if path.startswith("."):
        return False
    if "/." in path:
        return False
    return True


def iter_folder_files(path, recursive = True):
    if recursive:
        for dirpath, dirnames, filenames in os.walk(path, topdown = False):
            relative_path = os.path.relpath(dirpath,path)
            dirnames.sort()
            if "/." in relative_path:
                continue
            if relative_path == ".":
                relative_path = ""
            for f in sorted(filenames):
                if f.startswith("."):
                    continue
                fp = os.path.join(relative_path, f)
                yield fp
    else:
        for file in sorted(path):
            fp = os.path.join(path,file)
            if os.path.isdir(fp):
                continue
            if file.startswith("."):
                continue
            yield fp


def path2url(path):
    return pathname2url(path)

def safe_name(s):
    return safe_string(s, "-_")


def safe_path(s):
    return safe_string(s, "-_/")


def safe_string(s, valid):
    """ return a safe string, replace non alnum characters with _ . all characters in valid are considered valid. """
    return "".join([c if c.isalnum() or c in valid else "_" for c in s])