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

# Copyright 2018 Markus Binsteiner <makkus@frkl.io>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

DOCUMENTATION = """
---
module: stow
short_description: Manage links to dotfiles
"""

import os
from distutils.spawn import find_executable

from ansible.module_utils.basic import AnsibleModule

try:
    set
except NameError:
    from sets import Set as set

IGNORE_STRING = "freckle"

POTENTIAL_STOW_PATHS = [
    os.path.expanduser("~/.local/share/inaugurate/conda/bin"),
    os.path.expanduser("~/.local/bin"),
    os.path.expanduser("~/miniconda3/bin"),
    os.path.expanduser("~/anaconda/bin"),
]


def get_stow_bin(module):
    stow_bin = find_executable("stow")
    if not stow_bin:
        for path in POTENTIAL_STOW_PATHS:
            if os.path.isfile(os.path.join(path, "stow")):
                stow_bin = os.path.join(path, "stow")

    if not stow_bin:
        module.fail_json(msg="Could not find stow executable.")

    return stow_bin


def stow(module, stow_version):
    params = module.params

    # state = params['state']
    name = params["name"]
    source_dir = os.path.expanduser(params["source_dir"])
    target_dir = os.path.expanduser(params["target_dir"])
    delete_conflicts = params["delete_conflicts"]
    unstow = params["unstow"]

    if stow_version.startswith("1") or stow_version.startswith("2.0"):
        ignore_parameter = ""
    else:
        ignore_parameter = "--ignore={}".format(IGNORE_STRING)

    if unstow:
        cmd = "{} -v 2 {} -d {} -t {} -D {}".format(
            get_stow_bin(module), ignore_parameter, source_dir, target_dir, name
        )
    else:
        cmd = "{} -v 2 {} -d {} -t {} -S {}".format(
            get_stow_bin(module), ignore_parameter, source_dir, target_dir, name
        )

    rc, stdout, stderr = module.run_command(cmd, check_rc=False)

    if unstow:
        if rc == 0:
            changed = False
            if "UNLINK" in stderr:
                changed = True
            module.exit_json(changed=changed, stderr=stderr)
        else:
            module.fail_json(
                msg="failed to unstow ( {} ) {}: {}".format(cmd, name, stderr)
            )
    else:
        if rc == 0:
            changed = False
            if "LINK" in stderr:
                changed = True
            module.exit_json(changed=changed, stderr=stderr)
        else:
            if not delete_conflicts:
                module.fail_json(
                    msg="failed to stow ( {} ) {}: {}".format(cmd, name, stderr)
                )
            else:
                conflict_files = set()
                for line in stderr.split("\n"):
                    conflict_file = None
                    if not "neither a link nor a directory" in line:
                        continue
                    conflict_file = line.split()[-1]
                    conflict_files.add(conflict_file)

                for conflict_file in conflict_files:

                    cf_path = os.path.join(target_dir, conflict_file)
                    if os.path.exists(cf_path) and os.path.isfile(cf_path):
                        os.remove(cf_path)

                rc, stdout, stderr = module.run_command(cmd, check_rc=False)
                if rc == 0:
                    changed = False
                    if "LINK" in stderr:
                        changed = True

                    module.exit_json(
                        changed=changed,
                        stderr=stderr,
                        msg="Deleted existing files: {}".format(list(conflict_files)),
                    )
                else:
                    module.fail_json(
                        msg="failed to stow ( {} ) {}: {}".format(cmd, name, stderr)
                    )


def main():
    module = AnsibleModule(
        argument_spec=dict(
            # state=dict(default='present', choices=['present', 'absent']),
            name=dict(required=True),
            source_dir=dict(required=True),
            target_dir=dict(required=True),
            delete_conflicts=dict(required=False, default=False, type="bool"),
            use=dict(default="stow"),
            unstow=dict(required=False, default=False, type="bool"),
        )
    )

    cmd = "{} --version".format(get_stow_bin(module))
    rc, stdout, stderr = module.run_command(cmd, check_rc=False)

    if rc == 0:
        stow_version = stdout.split()[-1]
        # module.exit_json(changed=True, version=stow_version)
    else:
        module.fail_json("Can't execute/find 'stow': {}".format(stderr))

    stow(module, stow_version)


if __name__ == "__main__":
    main()