#!/usr/bin/env python
# -*- coding: utf-8 -*-

import os, sys, shutil
import argparse


def err(msg, die=None):
    sys.stderr.write(str(msg) + '\n')
    if die:
        sys.exit((die if type(die) is int else 1))

try:
    import pelican

    global themes_path
    themes_path = os.path.join(
        os.path.dirname(
            os.path.abspath(
                pelican.__file__
            )
        ),
        'themes'
    )
except:
    err('Cannot import pelican.\nYou must install Pelican in order to run this script.', -1)


__version__ = '0.1'
_BUILTIN_THEMES = ['simple', 'notmyidea']


def main():
    parser = argparse.ArgumentParser(description="""Install themes for Pelican""")

    parser.add_argument('-l', '--list', dest='list', action="store_true",
                        help="Show the themes already installed")
    parser.add_argument('-i', '--install', dest='to_install', nargs='+', metavar="theme path",
        help='The themes to install ')
    parser.add_argument('-r', '--remove', dest='to_remove', nargs='+', metavar="theme name",
        help='The themes to remove')
    parser.add_argument('-s', '--symlink', dest='to_symlink', nargs='+', metavar="theme path",
        help="Same as `--install', but create a symbolic link instead of copying the theme. Useful for theme development")
    parser.add_argument('-v', '--verbose', dest='verbose', action="store_true",
                        help="Verbose output")
    parser.add_argument('--version', action='version', version=__version__,
            help='Print the version of this script')
    args = parser.parse_args()


    if args.list:
        list_themes(args.verbose)
    else:

        if args.to_remove:
            if args.verbose:
                print('Removing themes...')

            for i in args.to_remove:
                remove(i, v=args.verbose)

        if args.to_install:
            if args.verbose:
                print('Installing themes...')

            for i in args.to_install:
                install(i, v=args.verbose)

        if args.to_symlink:
            if args.verbose:
                print('Linking themes...')

            for i in args.to_symlink:
                symlink(i, v=args.verbose)



def themes():
    for i in os.listdir(themes_path):
        e = os.path.join(themes_path, i)

        if os.path.isdir(e):
            if os.path.islink(e):
                yield (e, os.path.realpath(e))
            else:
                yield (e, None)


def list_themes(v=False):
    for t, l in themes():
        if not v:
            t = os.path.basename(t)
        if l:
            if v:
                print(t + (" (symbolic link to `" + l + "')"))
            else:
                print(t + '@')
        else:
            print(t)


def remove(theme_name, v=False):

    theme_name = theme_name.replace('/','')
    target = os.path.join(themes_path, theme_name)

    if theme_name in _BUILTIN_THEMES:
        err(theme_name + ' is a builtin theme.\nYou cannot remove a builtin theme with this script, remove it by hand if you want.')
    elif not os.path.exists(target):
        err(target + ' : no such file or directory')
    elif os.path.islink(target):
        if v:
            print('Removing link `' + target + "'")
        os.remove(target)
    elif os.path.isdir(target):
        if v:
            print('Removing directory `' + target + "'")
        shutil.rmtree(target)
    else:
        err(target + ' : not a valid theme') 


def install(path, v=False):
    if not os.path.exists(path):
        err(path + ' : no such file or directory')
    elif not os.path.isdir(path):
        err(path + ' : no a directory')
    else:
        theme_name = os.path.basename(os.path.normpath(path))
        theme_path = os.path.join(themes_path, theme_name)
        if os.path.exists(theme_path):
            err(path + ' : already exists')
        else:
            if v:
                print("Copying `{p}' to `{t}' ...".format(p=path, t=theme_path))
            try:
                shutil.copytree(path, theme_path)
            except Exception, e:
                err("Cannot copy `{p}' to `{t}':\n{e}".format(p=path, t=theme_path, e=str(e)))

def symlink(path, v=False):
    if not os.path.exists(path):
        err(path + ' : no such file or directory')
    elif not os.path.isdir(path):
        err(path + ' : no a directory')
    else:
        theme_name = os.path.basename(os.path.normpath(path))
        theme_path = os.path.join(themes_path, theme_name)
        if os.path.exists(theme_path):
            err(path + ' : already exists')
        else:
            if v:
                print("Linking `{p}' to `{t}' ...".format(p=path, t=theme_path))
            try:
                os.symlink(path, theme_path)
            except Exception, e:
                err("Cannot link `{p}' to `{t}':\n{e}".format(p=path, t=theme_path, e=str(e)))


    
if __name__ == '__main__':
    main()