#!/usr/bin/env python3
"""
project: Backuppy
version: 0.8
file: install.py
summary: python installer-script in CLI-mode
"""

# Standard library imports
import sys
import os
import time

# local imports
from languages import english
from languages import german

# local globals
# ----------------------
VERSION: str = "0.8"
EMAIL = "fotocoder@joschu.ch"
EXCLUDE_FILE = "exclude.txt"
BACKUPPY_SCRIPT = "Backuppy.sh"
# ----------------------
MYDIR = os.getcwd()
EXCLUDE: bool = False
SHELL = os.environ.get("SHELL")
HOME = os.environ.get("HOME")
LANG_EN = "English"
LANG_DE = "German"
LANGUAGE = LANG_EN
RSYNC_CMD: str = None

def set_language(language):
    global LANGUAGE
    LANGUAGE = language

def trace(message_txt):
    """ Print a formatted message to std out. """
    print("[  OK  ] " + message_txt)

def get_lang_text(search_str: str):
    global LANGUAGE
    """ Returns a string from the appropriate language file. """
    return_str: str = eval("english."  + search_str) 
    if LANGUAGE == LANG_DE:
        return_str = eval("german."  + search_str)
    return return_str

def main_install_cli():
    language = input("Hello, first of all, which language do you prefer: German [DE] or English [EN]?\n> ")
    if language.upper() == "DE":
        set_language(LANG_DE)
        print("Perfekt, nun ist das deutsche Sprachpaket aktiviert. Willkommen!\n")    
    else:
        print("Perfect, the English language package is now activated. Welcome!.\n")

    time.sleep(1)

    print("\n" + get_lang_text("intromsg1") + "\n")
    time.sleep(1)

    print("\n" + get_lang_text("intromsg2") + "\n")
    time.sleep(1)

    # which Rsync options are available and which one you want to use
    print(get_lang_text("rsyncopt") + "\n")
    time.sleep(1)

    # asks if you want to exclude files/directories from backup and creates an exclude file in case of Yes
    exclude = input(get_lang_text("excludefile1") + "\n> ")
    global EXCLUDE
    if exclude.upper() in ("J", "Y"):
        EXCLUDE = True
        print(get_lang_text("excludefile2") + "\n")
    else:
        EXCLUDE = False
        print(get_lang_text("excludefile3") + "\n")
    time.sleep(1)

    # Asks for the source directory which should be saved
    print(get_lang_text("srcdir1"))
    time.sleep(1)
    sourcedir = input(get_lang_text("srcdir2") + "\n> ")

    print(f"{get_lang_text('srcdir3_1')} {sourcedir} {get_lang_text('srcdir3_2')}")
    time.sleep(1)

    # asks for the destination directory in which the backup should be saved
    targetdir = input(get_lang_text("targetdir1") + "\n> ")
    print(f"{get_lang_text('targetdir2_1')} {targetdir} {get_lang_text('targetdir2_2')}")
    time.sleep(1)

    # collects all the information needed to execute the rsync command and creates it.
    print(get_lang_text("collect") + "\n")
    time.sleep(1)
    exclude_file = os.path.join(MYDIR, EXCLUDE_FILE)
    
    RSYNC_CMD = f"rsync -aqp --exclude-from={exclude_file} {sourcedir} {targetdir}"

    print(f"{RSYNC_CMD}")
    time.sleep(1)

    # Outro
    print(get_lang_text("outro1"))
    time.sleep(2)
    print(get_lang_text("outro2") + " " + EMAIL)

    return True, EXCLUDE, RSYNC_CMD

def create_exclude_file(directory, exclude_file):
    exclude_file = os.path.join(directory, exclude_file)
    with open(exclude_file, "w") as fExclude:
        trace(f"creating exclude-file '{exclude_file}'.")
        fExclude.write("\n")

def create_alias(shell, home_dir, directory, backuppy_script):
    # alias entry in .bashrc or .zshrc
    backuppy_script = os.path.join(directory, backuppy_script)
    alias_str = f"alias backuppy='sudo {backuppy_script}'"

    # Check for installed ZSH
    if shell.upper().find("ZSH") > 0:
        rc_filepath = os.path.join(home_dir, ".zshrc")
    # Check for installed BASH
    if shell.upper().find("BASH") > 0:
        rc_filepath = os.path.join(home_dir, ".bashrc")
    # Append our alias if not already existing
    if os.path.isfile(rc_filepath):
        fileRc = open(rc_filepath, "r")  # open file in read mode
        backuppy_entry_exists = False
        for line in fileRc:
            if "alias backuppy=" in line:
                backuppy_entry_exists = True
                break
        if not backuppy_entry_exists:
            trace(f"Writing {alias_str} to config file '{rc_filepath}'.")
            fileRc = open(rc_filepath, "a")  # open file in append mode
            fileRc.write("\n# Following line was created by Backuppy\n" + alias_str + "\n")
        fileRc.close()

def create_backuppy_script(directory, backuppy_script, rsync_cmd):
    # creates the file 'Backuppy.sh'
    backuppy_file = os.path.join(directory, backuppy_script)
    with open(backuppy_file, "w") as fBackuppy:
        trace(f"creating backuppy-file '{backuppy_file}'.")
        fBackuppy.write("#!/bin/bash\n" + rsync_cmd + "\n")
    
    os.chmod(backuppy_file, 0o777)  # make file executable

def do_the_install(is_exclude: bool, rsync_cmd: str):
    """ Creates scripts and entries based on environment variables. """

    if is_exclude:
        create_exclude_file(MYDIR, EXCLUDE_FILE)

    if rsync_cmd:
        create_backuppy_script(MYDIR, BACKUPPY_SCRIPT, rsync_cmd)
        create_alias(SHELL, HOME, MYDIR, BACKUPPY_SCRIPT)

def main(argv):
    trace(f"Starting Backuppy install.py v{VERSION}")
    is_finalized = False

    if argv and argv[0] == "--gui":
        from install_gui import main_install_gui
        trace("Starting GUI-version.")
        is_finalized, is_exclude, rsync_cmd = main_install_gui()  # collect user input via GUI and store in env. variables

    else:
        trace("Starting CLI-version.\n")
        is_finalized, is_exclude, rsync_cmd = main_install_cli()  # collect user input via CLI and store in env. variables
        if is_finalized:
            print("CLI finalized.")
        if is_exclude:
            print("exclude is true.")
        if rsync_cmd:
            print("rsync command returned: " + rsync_cmd)

    if is_finalized:
        do_the_install(is_exclude, rsync_cmd)

    trace("Ending Backuppy install.py")

if __name__ == '__main__':
    # sys.argv.append("--gui")  # TODO: disable for production
    sys.exit(main(sys.argv[1:]))