#!/usr/bin/python

# Copyright (c) 2018, Dag Wieers (@dagwieers) <dag@wieers.com>
# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
# SPDX-License-Identifier: GPL-3.0-or-later

from __future__ import annotations

DOCUMENTATION = r"""
module: read_csv
short_description: Read a CSV file
description:
  - Read a CSV file and return a list or a dictionary, containing one dictionary per row.
author:
  - Dag Wieers (@dagwieers)
extends_documentation_fragment:
  - community.general.attributes
attributes:
  check_mode:
    support: full
  diff_mode:
    support: none
options:
  path:
    description:
      - The CSV filename to read data from.
    type: path
    required: true
    aliases: [filename]
  key:
    description:
      - The column name used as a key for the resulting dictionary.
      - If O(key) is unset, the module returns a list of dictionaries, where each dictionary is a row in the CSV file.
    type: str
  dialect:
    description:
      - The CSV dialect to use when parsing the CSV file.
      - Possible values include V(excel), V(excel-tab) or V(unix).
    type: str
    default: excel
  fieldnames:
    description:
      - A list of field names for every column.
      - This is needed if the CSV does not have a header.
    type: list
    elements: str
  unique:
    description:
      - Whether the O(key) used is expected to be unique.
    type: bool
    default: true
  delimiter:
    description:
      - A one-character string used to separate fields.
      - When using this parameter, you change the default value used by O(dialect).
      - The default value depends on the dialect used.
    type: str
  skipinitialspace:
    description:
      - Whether to ignore any whitespaces immediately following the delimiter.
      - When using this parameter, you change the default value used by O(dialect).
      - The default value depends on the dialect used.
    type: bool
  strict:
    description:
      - Whether to raise an exception on bad CSV input.
      - When using this parameter, you change the default value used by O(dialect).
      - The default value depends on the dialect used.
    type: bool
seealso:
  - plugin: ansible.builtin.csvfile
    plugin_type: lookup
    description: Can be used to do selective lookups in CSV files from Jinja.
"""

EXAMPLES = r"""
# Example CSV file with header
#
#   name,uid,gid
#   dag,500,500
#   jeroen,501,500

# Read a CSV file and access user 'dag'
- name: Read users from CSV file and return a dictionary
  community.general.read_csv:
    path: users.csv
    key: name
  register: users
  delegate_to: localhost

- ansible.builtin.debug:
    msg: 'User {{ users.dict.dag.name }} has UID {{ users.dict.dag.uid }} and GID {{ users.dict.dag.gid }}'

# Read a CSV file and access the first item
- name: Read users from CSV file and return a list
  community.general.read_csv:
    path: users.csv
  register: users
  delegate_to: localhost

- ansible.builtin.debug:
    msg: 'User {{ users.list.1.name }} has UID {{ users.list.1.uid }} and GID {{ users.list.1.gid }}'

# Example CSV file without header and semi-colon delimiter
#
#   dag;500;500
#   jeroen;501;500

# Read a CSV file without headers
- name: Read users from CSV file and return a list
  community.general.read_csv:
    path: users.csv
    fieldnames: name,uid,gid
    delimiter: ';'
  register: users
  delegate_to: localhost
"""

RETURN = r"""
dict:
  description: The CSV content as a dictionary.
  returned: success
  type: dict
  sample:
    dag:
      name: dag
      uid: 500
      gid: 500
    jeroen:
      name: jeroen
      uid: 501
      gid: 500
list:
  description: The CSV content as a list.
  returned: success
  type: list
  sample:
    - name: dag
      uid: 500
      gid: 500
    - name: jeroen
      uid: 501
      gid: 500
"""

from ansible.module_utils.basic import AnsibleModule

from ansible_collections.community.general.plugins.module_utils.csv import (
    initialize_dialect,
    read_csv,
    CSVError,
    DialectNotAvailableError,
    CustomDialectFailureError,
)


def main():
    module = AnsibleModule(
        argument_spec=dict(
            path=dict(type="path", required=True, aliases=["filename"]),
            dialect=dict(type="str", default="excel"),
            key=dict(type="str", no_log=False),
            fieldnames=dict(type="list", elements="str"),
            unique=dict(type="bool", default=True),
            delimiter=dict(type="str"),
            skipinitialspace=dict(type="bool"),
            strict=dict(type="bool"),
        ),
        supports_check_mode=True,
    )

    path = module.params["path"]
    dialect = module.params["dialect"]
    key = module.params["key"]
    fieldnames = module.params["fieldnames"]
    unique = module.params["unique"]

    dialect_params = {
        "delimiter": module.params["delimiter"],
        "skipinitialspace": module.params["skipinitialspace"],
        "strict": module.params["strict"],
    }

    try:
        dialect = initialize_dialect(dialect, **dialect_params)
    except (CustomDialectFailureError, DialectNotAvailableError) as e:
        module.fail_json(msg=f"{e}")

    try:
        with open(path, "rb") as f:
            data = f.read()
    except (IOError, OSError) as e:
        module.fail_json(msg=f"Unable to open file: {e}")

    reader = read_csv(data, dialect, fieldnames)

    if key and key not in reader.fieldnames:
        module.fail_json(msg=f"Key '{key}' was not found in the CSV header fields: {', '.join(reader.fieldnames)}")

    data_dict = dict()
    data_list = list()

    if key is None:
        try:
            for row in reader:
                data_list.append(row)
        except CSVError as e:
            module.fail_json(msg=f"Unable to process file: {e}")
    else:
        try:
            for row in reader:
                if unique and row[key] in data_dict:
                    module.fail_json(msg=f"Key '{key}' is not unique for value '{row[key]}'")
                data_dict[row[key]] = row
        except CSVError as e:
            module.fail_json(msg=f"Unable to process file: {e}")

    module.exit_json(dict=data_dict, list=data_list)


if __name__ == "__main__":
    main()