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

# Copyright: (c) 2014, Ruggero Marchei <ruggero.marchei@daemonzone.net>
# Copyright: (c) 2015, Brian Coca <bcoca@ansible.com>
# Copyright: (c) 2017, Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import absolute_import, division, print_function
__metaclass__ = type

ANSIBLE_METADATA = {'metadata_version': '1.1',
                    'status': ['stableinterface'],
                    'supported_by': 'core'}

DOCUMENTATION = r'''
---
module: find
author: Brian Coca (based on Ruggero Marchei's Tidy)
version_added: "2.0"
short_description: Return a list of files based on specific criteria
description:
    - Return a list of files based on specific criteria. Multiple criteria are AND'd together.
    - For Windows targets, use the M(win_find) module instead.
options:
    age:
        description:
            - Select files whose age is equal to or greater than the specified time.
              Use a negative age to find files equal to or less than the specified time.
              You can choose seconds, minutes, hours, days, or weeks by specifying the
              first letter of any of those words (e.g., "1w").
    patterns:
        default: '*'
        description:
            - One or more (shell or regex) patterns, which type is controlled by C(use_regex) option.
            - The patterns restrict the list of files to be returned to those whose basenames match at
              least one of the patterns specified. Multiple patterns can be specified using a list.
        aliases: ['pattern']
    contains:
        description:
            - One or more regex patterns which should be matched against the file content.
    paths:
        required: true
        aliases: [ name, path ]
        description:
            - List of paths of directories to search. All paths must be fully qualified.
    file_type:
        description:
            - Type of file to select.
            - The 'link' and 'any' choices were added in version 2.3.
        choices: [ any, directory, file, link ]
        default: file
    recurse:
        default: 'no'
        choices: [ 'no', 'yes' ]
        description:
            - If target is a directory, recursively descend into the directory looking for files.
    size:
        description:
            - Select files whose size is equal to or greater than the specified size.
              Use a negative size to find files equal to or less than the specified size.
              Unqualified values are in bytes, but b, k, m, g, and t can be appended to specify
              bytes, kilobytes, megabytes, gigabytes, and terabytes, respectively.
              Size is not evaluated for directories.
    age_stamp:
        default: mtime
        choices: [ atime, ctime, mtime ]
        description:
            - Choose the file property against which we compare age.
    hidden:
        default: 'no'
        choices: [ 'no', 'yes' ]
        description:
            - Set this to true to include hidden files, otherwise they'll be ignored.
    follow:
        default: 'no'
        choices: [ 'no', 'yes' ]
        description:
            - Set this to true to follow symlinks in path for systems with python 2.6+.
    get_checksum:
        default: 'no'
        choices: [ 'no', 'yes' ]
        description:
            - Set this to true to retrieve a file's sha1 checksum.
    use_regex:
        default: 'no'
        choices: [ 'no', 'yes' ]
        description:
            - If false the patterns are file globs (shell) if true they are python regexes.
notes:
    - For Windows targets, use the M(win_find) module instead.
'''


EXAMPLES = r'''
- name: Recursively find /tmp files older than 2 days
  find:
    paths: /tmp
    age: 2d
    recurse: yes

- name: Recursively find /tmp files older than 4 weeks and equal or greater than 1 megabyte
  find:
    paths: /tmp
    age: 4w
    size: 1m
    recurse: yes

- name: Recursively find /var/tmp files with last access time greater than 3600 seconds
  find:
    paths: /var/tmp
    age: 3600
    age_stamp: atime
    recurse: yes

- name: Find /var/log files equal or greater than 10 megabytes ending with .old or .log.gz
  find:
    paths: /var/log
    patterns: '*.old,*.log.gz'
    size: 10m

# Note that YAML double quotes require escaping backslashes but yaml single quotes do not.
- name: Find /var/log files equal or greater than 10 megabytes ending with .old or .log.gz via regex
  find:
    paths: /var/log
    patterns: "^.*?\\.(?:old|log\\.gz)$"
    size: 10m
    use_regex: yes
'''

RETURN = r'''
files:
    description: all matches found with the specified criteria (see stat module for full output of each dictionary)
    returned: success
    type: list
    sample: [
        { path: "/var/tmp/test1",
          mode: "0644",
          "...": "...",
          checksum: 16fac7be61a6e4591a33ef4b729c5c3302307523
        },
        { path: "/var/tmp/test2",
          "...": "..."
        },
        ]
matched:
    description: number of matches
    returned: success
    type: string
    sample: 14
examined:
    description: number of filesystem objects looked at
    returned: success
    type: string
    sample: 34
'''

import fnmatch
import os
import re
import stat
import sys
import time

from ansible.module_utils.basic import AnsibleModule


def pfilter(f, patterns=None, use_regex=False):
    '''filter using glob patterns'''

    if patterns is None:
        return True

    if use_regex:
        for p in patterns:
            r = re.compile(p)
            if r.match(f):
                return True
    else:

        for p in patterns:
            if fnmatch.fnmatch(f, p):
                return True

    return False


def agefilter(st, now, age, timestamp):
    '''filter files older than age'''
    if age is None:
        return True
    elif age >= 0 and now - st.__getattribute__("st_%s" % timestamp) >= abs(age):
        return True
    elif age < 0 and now - st.__getattribute__("st_%s" % timestamp) <= abs(age):
        return True
    return False


def sizefilter(st, size):
    '''filter files greater than size'''
    if size is None:
        return True
    elif size >= 0 and st.st_size >= abs(size):
        return True
    elif size < 0 and st.st_size <= abs(size):
        return True
    return False


def contentfilter(fsname, pattern):
    '''filter files which contain the given expression'''
    if pattern is None:
        return True

    try:
        f = open(fsname)
        prog = re.compile(pattern)
        for line in f:
            if prog.match(line):
                f.close()
                return True

        f.close()
    except:
        pass

    return False


def statinfo(st):
    return {
        'mode': "%04o" % stat.S_IMODE(st.st_mode),
        'isdir': stat.S_ISDIR(st.st_mode),
        'ischr': stat.S_ISCHR(st.st_mode),
        'isblk': stat.S_ISBLK(st.st_mode),
        'isreg': stat.S_ISREG(st.st_mode),
        'isfifo': stat.S_ISFIFO(st.st_mode),
        'islnk': stat.S_ISLNK(st.st_mode),
        'issock': stat.S_ISSOCK(st.st_mode),
        'uid': st.st_uid,
        'gid': st.st_gid,
        'size': st.st_size,
        'inode': st.st_ino,
        'dev': st.st_dev,
        'nlink': st.st_nlink,
        'atime': st.st_atime,
        'mtime': st.st_mtime,
        'ctime': st.st_ctime,
        'wusr': bool(st.st_mode & stat.S_IWUSR),
        'rusr': bool(st.st_mode & stat.S_IRUSR),
        'xusr': bool(st.st_mode & stat.S_IXUSR),
        'wgrp': bool(st.st_mode & stat.S_IWGRP),
        'rgrp': bool(st.st_mode & stat.S_IRGRP),
        'xgrp': bool(st.st_mode & stat.S_IXGRP),
        'woth': bool(st.st_mode & stat.S_IWOTH),
        'roth': bool(st.st_mode & stat.S_IROTH),
        'xoth': bool(st.st_mode & stat.S_IXOTH),
        'isuid': bool(st.st_mode & stat.S_ISUID),
        'isgid': bool(st.st_mode & stat.S_ISGID),
    }


def main():
    module = AnsibleModule(
        argument_spec=dict(
            paths=dict(type='list', required=True, aliases=['name', 'path']),
            patterns=dict(type='list', default=['*'], aliases=['pattern']),
            contains=dict(type='str'),
            file_type=dict(type='str', default="file", choices=['any', 'directory', 'file', 'link']),
            age=dict(type='str'),
            age_stamp=dict(type='str', default="mtime", choices=['atime', 'mtime', 'ctime']),
            size=dict(type='str'),
            recurse=dict(type='bool', default='no'),
            hidden=dict(type='bool', default='no'),
            follow=dict(type='bool', default='no'),
            get_checksum=dict(type='bool', default='no'),
            use_regex=dict(type='bool', default='no'),
        ),
        supports_check_mode=True,
    )

    params = module.params

    filelist = []

    if params['age'] is None:
        age = None
    else:
        # convert age to seconds:
        m = re.match("^(-?\d+)(s|m|h|d|w)?$", params['age'].lower())
        seconds_per_unit = {"s": 1, "m": 60, "h": 3600, "d": 86400, "w": 604800}
        if m:
            age = int(m.group(1)) * seconds_per_unit.get(m.group(2), 1)
        else:
            module.fail_json(age=params['age'], msg="failed to process age")

    if params['size'] is None:
        size = None
    else:
        # convert size to bytes:
        m = re.match("^(-?\d+)(b|k|m|g|t)?$", params['size'].lower())
        bytes_per_unit = {"b": 1, "k": 1024, "m": 1024**2, "g": 1024**3, "t": 1024**4}
        if m:
            size = int(m.group(1)) * bytes_per_unit.get(m.group(2), 1)
        else:
            module.fail_json(size=params['size'], msg="failed to process size")

    now = time.time()
    msg = ''
    looked = 0
    for npath in params['paths']:
        npath = os.path.expanduser(os.path.expandvars(npath))
        if os.path.isdir(npath):
            ''' ignore followlinks for python version < 2.6 '''
            for root, dirs, files in (sys.version_info < (2, 6, 0) and os.walk(npath)) or os.walk(npath, followlinks=params['follow']):
                looked = looked + len(files) + len(dirs)
                for fsobj in (files + dirs):
                    fsname = os.path.normpath(os.path.join(root, fsobj))

                    if os.path.basename(fsname).startswith('.') and not params['hidden']:
                        continue

                    try:
                        st = os.lstat(fsname)
                    except:
                        msg += "%s was skipped as it does not seem to be a valid file or it cannot be accessed\n" % fsname
                        continue

                    r = {'path': fsname}
                    if params['file_type'] == 'any':
                        if pfilter(fsobj, params['patterns'], params['use_regex']) and agefilter(st, now, age, params['age_stamp']):
                            r.update(statinfo(st))
                            filelist.append(r)
                    elif stat.S_ISDIR(st.st_mode) and params['file_type'] == 'directory':
                        if pfilter(fsobj, params['patterns'], params['use_regex']) and agefilter(st, now, age, params['age_stamp']):

                            r.update(statinfo(st))
                            filelist.append(r)

                    elif stat.S_ISREG(st.st_mode) and params['file_type'] == 'file':
                        if pfilter(fsobj, params['patterns'], params['use_regex']) and \
                           agefilter(st, now, age, params['age_stamp']) and \
                           sizefilter(st, size) and \
                           contentfilter(fsname, params['contains']):

                            r.update(statinfo(st))
                            if params['get_checksum']:
                                r['checksum'] = module.sha1(fsname)
                            filelist.append(r)

                    elif stat.S_ISLNK(st.st_mode) and params['file_type'] == 'link':
                        if pfilter(fsobj, params['patterns'], params['use_regex']) and agefilter(st, now, age, params['age_stamp']):
                            r.update(statinfo(st))
                            filelist.append(r)

                if not params['recurse']:
                    break
        else:
            msg += "%s was skipped as it does not seem to be a valid directory or it cannot be accessed\n" % npath

    matched = len(filelist)
    module.exit_json(files=filelist, changed=False, msg=msg, matched=matched, examined=looked)


if __name__ == '__main__':
    main()