# -*- coding: utf-8 -*-

# Copyright 2015 Mike Fährmann
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.

import os
import sys
import shutil
import platform

def select():
    """Automatically select a suitable printer class"""
    if hasattr(sys.stdout, "isatty") and sys.stdout.isatty():
        if _color_supported():
            return ColorPrinter
        else:
            return TerminalPrinter
    else:
        return Printer


class Printer():

    @staticmethod
    def start(path):
        """Print a message indicating the start of a download"""
        pass

    @staticmethod
    def skip(path):
        """Print a message indicating that a download has been skipped"""
        print("#", path, sep="", flush=True)

    @staticmethod
    def success(path, tries):
        """Print a message indicating the completion of a download"""
        print(path, flush=True)

    @staticmethod
    def error(file, error, tries, max_tries):
        """Print a message indicating an error during download"""
        pass


class TerminalPrinter():

    @staticmethod
    def start(path):
        """Print a message indicating the start of a download"""
        print(_shorten(" "+path), end="", flush=True)

    @staticmethod
    def skip(path):
        """Print a message indicating that a download has been skipped"""
        print(_shorten("#"+path))

    @staticmethod
    def success(path, tries):
        """Print a message indicating the completion of a download"""
        if tries == 0:
            print("\r", end="")
        print("\r", _shorten("✔" + path), sep="")

    @staticmethod
    def error(file, error, tries, max_tries):
        """Print a message indicating an error during download"""
        if tries <= 1 and hasattr(file, "name"):
            print("\r", _shorten("❌" + file.name), sep="")
        print("[Error] ", error, " (", tries, "/", max_tries, ")", sep="")


class ColorPrinter():

    @staticmethod
    def start(path):
        """Print a message indicating the start of a download"""
        print(_shorten(path), end="", flush=True)

    @staticmethod
    def skip(path):
        """Print a message indicating that a download has been skipped"""
        print("\033[2m", _shorten(path), "\033[0m", sep="")

    @staticmethod
    def success(path, tries):
        """Print a message indicating the completion of a download"""
        if tries == 0:
            print("\r", end="")
        print("\r\033[1;32m", _shorten(path), "\033[0m", sep="")

    @staticmethod
    def error(file, error, tries, max_tries):
        """Print a message indicating an error during download"""
        if tries <= 1 and hasattr(file, "name"):
            print("\r\033[1;31m", _shorten(file.name), sep="")
        print("\033[0;31m[Error]\033[0m ", error, " (", tries, "/", max_tries, ")", sep="")


def _shorten(txt):
    """Reduce the length of 'txt' to the width of the terminal"""
    width = shutil.get_terminal_size().columns
    if len(txt) > width:
        hwidth = width // 2
        return "".join((txt[:hwidth-1], "…", txt[-hwidth-(width%2):]))
    return txt

def _color_supported():
    """Return True if a terminal supports colors"""
    if platform.system() == "Windows":
        return os.environ.get("TERM") == "ANSI"
    return True