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

# (c) 2016, Cumulus Networks <ce-ceng@cumulusnetworks.com>
#
# 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: cl_img_install
version_added: "2.1"
author: "Cumulus Networks (@CumulusLinux)"
short_description: Install a different Cumulus Linux version.
description:
    - install a different version of Cumulus Linux in the inactive slot. For
      more details go the Image Management User Guide at
      U(http://docs.cumulusnetworks.com/).
options:
    src:
        description:
            - The full path to the Cumulus Linux binary image. Can be a local path,
              http or https URL. If the code version is in the name of the file,
              the module will assume this is the version of code you wish to
              install.
        required: true
    version:
        description:
            - Inform the module of the exact version one is installing. This
              overrides the automatic check of version in the file name. For
              example, if the binary file name is called CumulusLinux-2.2.3.bin,
              and version is set to '2.5.0', then the module will assume it is
              installing '2.5.0' not '2.2.3'. If version is not included, then
              the module will assume '2.2.3' is the version to install.
        default: None
        required: false
    switch_slot:
        description:
            - Switch slots after installing the image.
              To run the installed code, reboot the switch.
        choices: ['yes', 'no']
        default: 'no'
        required: false

requirements: ["Cumulus Linux OS"]

'''
EXAMPLES = '''
Example playbook entries using the cl_img_install module

## Download and install the image from a webserver.

   - name: install image using using http url. Switch slots so the subsequent
     will load the new version
      cl_img_install: version=2.0.1
          src='http://10.1.1.1/CumulusLinux-2.0.1.bin'
          switch_slot=yes

## Copy the software from the ansible server to the switch.
## The module will get the code version from the filename
## The code will be installed in the alternate slot but the slot will not be primary
## A subsequent reload will not run the new code

    - name: download cumulus linux to local system
      get_url: src=ftp://cumuluslinux.bin dest=/root/CumulusLinux-2.0.1.bin

    - name: install image from local filesystem. Get version from the filename
      cl_img_install:  src='/root/CumulusLinux-2.0.1.bin'


## If the image name has been changed from the original name, use the `version` option
## to inform the module exactly what code version is been installed

    - name: download cumulus linux to local system
      get_url: src=ftp://CumulusLinux-2.0.1.bin dest=/root/image.bin

    - name: install image and switch slots. only reboot needed
      cl_img_install: version=2.0.1 src=/root/image.bin switch_slot=yes'
'''

RETURN = '''
changed:
    description: whether the interface was changed
    returned: changed
    type: bool
    sample: True
msg:
    description: human-readable report of success or failure
    returned: always
    type: string
    sample: "interface bond0 config updated"
'''


def check_url(module, url):
    parsed_url = urlparse(url)
    if len(parsed_url.path) > 0:
        sch = parsed_url.scheme
        if (sch == 'http' or sch == 'https' or len(parsed_url.scheme) == 0):
            return True
    module.fail_json(msg="Image Path URL. Wrong Format %s" % (url))
    return False


def run_cl_cmd(module, cmd, check_rc=True):
    try:
        (rc, out, err) = module.run_command(cmd, check_rc=check_rc)
    except Exception:
        e = get_exception()
        module.fail_json(msg=e.strerror)
    # trim last line as it is always empty
    ret = out.splitlines()
    return ret


def get_slot_info(module):
    slots = {}
    slots['1'] = {}
    slots['2'] = {}
    active_slotnum = get_active_slot(module)
    primary_slotnum = get_primary_slot_num(module)
    for _num in range(1, 3):
        slot = slots[str(_num)]
        slot['version'] = get_slot_version(module, str(_num))
        if _num == int(active_slotnum):
            slot['active'] = True
        if _num == int(primary_slotnum):
            slot['primary'] = True
    return slots


def get_slot_version(module, slot_num):
    lsb_release = check_mnt_root_lsb_release(slot_num)
    switch_firm_ver = check_fw_print_env(module, slot_num)
    _version = module.sw_version
    if lsb_release == _version or switch_firm_ver == _version:
        return _version
    elif lsb_release:
        return lsb_release
    else:
        return switch_firm_ver


def check_mnt_root_lsb_release(slot_num):
    _path = '/mnt/root-rw/config%s/etc/lsb-release' % (slot_num)
    try:
        lsb_release = open(_path)
        lines = lsb_release.readlines()
        for line in lines:
            _match = re.search('DISTRIB_RELEASE=([0-9a-zA-Z.]+)', line)
            if _match:
                return _match.group(1).split('-')[0]
    except:
        pass
    return None


def check_fw_print_env(module, slot_num):
    cmd = None
    if platform.machine() == 'ppc':
        cmd = "/usr/sbin/fw_printenv -n cl.ver%s" % (slot_num)
        fw_output = run_cl_cmd(module, cmd)
        return fw_output[0].split('-')[0]
    elif platform.machine() == 'x86_64':
        cmd = "/usr/bin/grub-editenv list"
        grub_output = run_cl_cmd(module, cmd)
        for _line in grub_output:
            _regex_str = re.compile('cl.ver' + slot_num + '=([\w.]+)-')
            m0 = re.match(_regex_str, _line)
            if m0:
                return m0.group(1)



def get_primary_slot_num(module):
    cmd = None
    if platform.machine() == 'ppc':
        cmd = "/usr/sbin/fw_printenv -n cl.active"
        return ''.join(run_cl_cmd(module, cmd))
    elif platform.machine() == 'x86_64':
        cmd = "/usr/bin/grub-editenv list"
        grub_output = run_cl_cmd(module, cmd)
        for _line in grub_output:
            _regex_str = re.compile('cl.active=(\d)')
            m0 = re.match(_regex_str, _line)
            if m0:
                return m0.group(1)


def get_active_slot(module):
    try:
        cmdline = open('/proc/cmdline').readline()
    except:
        module.fail_json(msg='Failed to open /proc/cmdline. ' +
                         'Unable to determine active slot')

    _match = re.search('active=(\d+)', cmdline)
    if _match:
        return _match.group(1)
    return None


def install_img(module):
    src = module.params.get('src')
    _version = module.sw_version
    app_path = '/usr/cumulus/bin/cl-img-install -f %s' % (src)
    run_cl_cmd(module, app_path)
    perform_switch_slot = module.params.get('switch_slot')
    if perform_switch_slot is True:
        check_sw_version(module)
    else:
        _changed = True
        _msg = "Cumulus Linux Version " + _version + " successfully" + \
            " installed in alternate slot"
        module.exit_json(changed=_changed, msg=_msg)


def switch_slot(module, slotnum):
    _switch_slot = module.params.get('switch_slot')
    if _switch_slot is True:
        app_path = '/usr/cumulus/bin/cl-img-select %s' % (slotnum)
        run_cl_cmd(module, app_path)


def determine_sw_version(module):
    _version = module.params.get('version')
    _filename = ''
    # Use _version if user defines it
    if _version:
        module.sw_version = _version
        return
    else:
        _filename = module.params.get('src').split('/')[-1]
        _match = re.search('\d+\W\d+\W\w+', _filename)
        if _match:
            module.sw_version = re.sub('\W', '.', _match.group())
            return
    _msg = 'Unable to determine version from file %s' % (_filename)
    module.exit_json(changed=False, msg=_msg)


def check_sw_version(module):
    slots = get_slot_info(module)
    _version = module.sw_version
    perform_switch_slot = module.params.get('switch_slot')
    for _num, slot in slots.items():
        if slot['version'] == _version:
            if 'active' in slot:
                _msg = "Version %s is installed in the active slot" \
                    % (_version)
                module.exit_json(changed=False,  msg=_msg)
            else:
                _msg = "Version " + _version + \
                    " is installed in the alternate slot. "
                if 'primary' not in slot:
                    if perform_switch_slot is True:
                        switch_slot(module, _num)
                        _msg = _msg + \
                            "cl-img-select has made the alternate " + \
                            "slot the primary slot. " +\
                            "Next reboot, switch will load " + _version + "."
                        module.exit_json(changed=True, msg=_msg)
                    else:
                        _msg = _msg + \
                            "Next reboot will not load " + _version + ". " + \
                            "switch_slot keyword set to 'no'."
                        module.exit_json(changed=False, msg=_msg)
                else:
                    if perform_switch_slot is True:
                        _msg = _msg + \
                            "Next reboot, switch will load " + _version + "."
                        module.exit_json(changed=False, msg=_msg)
                    else:
                        _msg = _msg + \
                            'switch_slot set to "no". ' + \
                            'No further action to take'
                        module.exit_json(changed=False, msg=_msg)


def main():
    module = AnsibleModule(
        argument_spec=dict(
            src=dict(required=True, type='str'),
            version=dict(type='str'),
            switch_slot=dict(type='bool', choices=BOOLEANS, default=False),
        ),
    )

    determine_sw_version(module)
    _url = module.params.get('src')

    check_sw_version(module)

    check_url(module, _url)

    install_img(module)


# import module snippets
from ansible.module_utils.basic import *
# incompatible with ansible 1.4.4 - ubuntu 12.04 version
# from ansible.module_utils.urls import *
from urlparse import urlparse
import re

if __name__ == '__main__':
    main()