# Copyright 2020 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Model objects for histograms.xml contents."""

import re

import setup_modules  # pylint: disable=unused-import

import chromium_src.tools.metrics.common.models as models

_OWNER_TYPE = models.TextNodeType('owner', single_line=True)
# If present, it's intentional that the histogram is currently expired and
# automation should not suggest for its implementation to be cleaned up.
_EXPIRED_INTENTIONALLY_TYPE = models.TextNodeType('expired_intentionally')
_COMPONENT_TYPE = models.TextNodeType('component', single_line=True)
_SUMMARY_TYPE = models.TextNodeType('summary', single_line=True)

# A key for sorting XML nodes by the lower case of the value of |attribute|.
_LOWERCASE_FN = lambda attribute: lambda node: node.get(attribute).lower()

# A key for sorting XML nodes by the value of |attribute|, cast as integer.
_INTEGER_FN = lambda attribute: lambda node: int(node.get(attribute))

# A constant function as the sorting key for nodes whose orderings should be
# kept as given in the XML file within their parent node.
_KEEP_ORDER = lambda node: 1


# A function for natural-sorting XML nodes, used for sorting <suffix> by their
# name attribute in a way that humans understand.
# i.e. "suffix11" should come after "suffix2"
def _NaturalSortByName(node):
  """Sort by name, ordering numbers in the way humans expect."""
  # See: https://blog.codinghorror.com/sorting-for-humans-natural-sort-order/
  name = node.get('name').lower()
  convert = lambda text: int(text) if text.isdigit() else text
  return [convert(c) for c in re.split('([0-9]+)', name)]


# The following types are used for enums.xml.
_INT_TYPE = models.ObjectNodeType(
  'int',
  attributes=[
    ('value', str, r'^[-1]|[0-9]+$'),
    ('label', str, None),
  ],
  required_attributes=['value'],
  keep_inner_text=True,
  single_line=True,
)

_ENUM_TYPE = models.ObjectNodeType(
  'enum',
  attributes=[
    ('name', str, r'^[A-Za-z0-9_.]+$'),
  ],
  required_attributes=['name'],
  alphabetization=[
    (_SUMMARY_TYPE.tag, _KEEP_ORDER),
    (_INT_TYPE.tag, _INTEGER_FN('value')),
  ],
  extra_newlines=(1, 1, 1),
  children=[
    models.ChildType(_SUMMARY_TYPE.tag, _SUMMARY_TYPE, multiple=False),
    models.ChildType(_INT_TYPE.tag, _INT_TYPE, multiple=True),
  ],
)

_ENUMS_TYPE = models.ObjectNodeType(
  'enums',
  alphabetization=[
    (_ENUM_TYPE.tag, _LOWERCASE_FN('name')),
  ],
  extra_newlines=(2, 1, 1),
  indent=False,
  children=[
    models.ChildType(_ENUM_TYPE.tag, _ENUM_TYPE, multiple=True),
  ],
)

# The following types are used for histograms.xml.
IMPROVEMENT_DIRECTION_HIGHER_IS_BETTER = 'HIGHER_IS_BETTER'
IMPROVEMENT_DIRECTION_LOWER_IS_BETTER = 'LOWER_IS_BETTER'
IMPROVEMENT_DIRECTION_NEITHER_IS_BETTER = 'NEITHER_IS_BETTER'

IMPROVEMENT_DIRECTION_VALID_VALUES = (
  IMPROVEMENT_DIRECTION_HIGHER_IS_BETTER,
  IMPROVEMENT_DIRECTION_LOWER_IS_BETTER,
  IMPROVEMENT_DIRECTION_NEITHER_IS_BETTER,
)

_IMPROVEMENT_TYPE = models.ObjectNodeType(
  'improvement',
  attributes=[
    (
      'direction',
      str,
      r'^(' + '|'.join(IMPROVEMENT_DIRECTION_VALID_VALUES) + ')$',
    ),
  ],
  required_attributes=['direction'],
  keep_inner_text=False,
  single_line=True,
)

_VARIANT_TYPE = models.ObjectNodeType(
  'variant',
  attributes=[
    ('name', str, None),
    ('summary', str, None),
  ],
  required_attributes=['name'],
  alphabetization=[
    (_OWNER_TYPE.tag, _KEEP_ORDER),
  ],
  children=[
    models.ChildType(_OWNER_TYPE.tag, _OWNER_TYPE, multiple=True),
  ],
)

_VARIANTS_TYPE = models.ObjectNodeType(
  'variants',
  attributes=[
    ('name', str, None),
  ],
  required_attributes=['name'],
  alphabetization=[(_VARIANT_TYPE.tag, _NaturalSortByName)],
  extra_newlines=(1, 1, 1),
  children=[
    models.ChildType(_VARIANT_TYPE.tag, _VARIANT_TYPE, multiple=True),
  ],
)

_TOKEN_TYPE = models.ObjectNodeType(
  'token',
  attributes=[('key', str, None), ('variants', str, None)],
  required_attributes=['key'],
  alphabetization=[(_VARIANT_TYPE.tag, _NaturalSortByName)],
  children=[
    models.ChildType(_VARIANT_TYPE.tag, _VARIANT_TYPE, multiple=True),
  ],
)

_EXPIRED_AFTER_RE = (
  r'^$|^\d{4}\-(0?[1-9]|1[012])\-(0?[1-9]|[12][0-9]|3[01])$|^M[0-9]+$|^never$'
)

_HISTOGRAM_TYPE = models.ObjectNodeType(
  'histogram',
  attributes=[
    ('name', str, None),
    ('enum', str, r'^[A-Za-z0-9._]*$'),
    ('units', str, None),
    ('expires_after', str, _EXPIRED_AFTER_RE),
  ],
  required_attributes=['name'],
  alphabetization=[
    (_EXPIRED_INTENTIONALLY_TYPE.tag, _KEEP_ORDER),
    (_OWNER_TYPE.tag, _KEEP_ORDER),
    (_COMPONENT_TYPE.tag, _KEEP_ORDER),
    (_IMPROVEMENT_TYPE.tag, _KEEP_ORDER),
    (_SUMMARY_TYPE.tag, _KEEP_ORDER),
    (_TOKEN_TYPE.tag, _KEEP_ORDER),
  ],
  extra_newlines=(1, 1, 1),
  children=[
    models.ChildType(
      _EXPIRED_INTENTIONALLY_TYPE.tag,
      _EXPIRED_INTENTIONALLY_TYPE,
      multiple=False,
    ),
    models.ChildType(_OWNER_TYPE.tag, _OWNER_TYPE, multiple=True),
    models.ChildType(_COMPONENT_TYPE.tag, _COMPONENT_TYPE, multiple=True),
    models.ChildType(_SUMMARY_TYPE.tag, _SUMMARY_TYPE, multiple=False),
    models.ChildType(_TOKEN_TYPE.tag, _TOKEN_TYPE, multiple=True),
    models.ChildType(_IMPROVEMENT_TYPE.tag, _IMPROVEMENT_TYPE, multiple=False),
  ],
)

_HISTOGRAMS_TYPE = models.ObjectNodeType(
  'histograms',
  alphabetization=[
    (_VARIANTS_TYPE.tag, _LOWERCASE_FN('name')),
    (_HISTOGRAM_TYPE.tag, _LOWERCASE_FN('name')),
  ],
  extra_newlines=(2, 1, 1),
  indent=False,
  children=[
    models.ChildType(_VARIANTS_TYPE.tag, _VARIANTS_TYPE, multiple=True),
    models.ChildType(_HISTOGRAM_TYPE.tag, _HISTOGRAM_TYPE, multiple=True),
  ],
)

_SUFFIX_TYPE = models.ObjectNodeType(
  'suffix',
  attributes=[
    ('base', str, r'^$|^true$|^false$'),
    ('name', str, None),
    ('label', str, None),
  ],
  required_attributes=['name'],
)

_WITH_SUFFIX_TYPE = models.ObjectNodeType(
  'with-suffix',
  attributes=[
    ('name', str, None),
  ],
  required_attributes=['name'],
)

_AFFECTED_HISTOGRAM_TYPE = models.ObjectNodeType(
  'affected-histogram',
  attributes=[
    ('name', str, None),
  ],
  required_attributes=['name'],
  children=[
    models.ChildType(_WITH_SUFFIX_TYPE.tag, _WITH_SUFFIX_TYPE, multiple=True),
  ],
)

_HISTOGRAM_SUFFIXES_TYPE = models.ObjectNodeType(
  'histogram_suffixes',
  attributes=[
    ('name', str, r'^$|^[A-Za-z0-9_.]+$'),
    ('separator', str, r'^$|^[\._]+$'),
    ('ordering', str, r'^$|suffix|^prefix(,[0-9]+)?$'),
  ],
  required_attributes=['name', 'separator'],
  alphabetization=[
    (_SUFFIX_TYPE.tag, _NaturalSortByName),
    (_AFFECTED_HISTOGRAM_TYPE.tag, _LOWERCASE_FN('name')),
  ],
  extra_newlines=(1, 1, 1),
  children=[
    models.ChildType(_OWNER_TYPE.tag, _OWNER_TYPE, multiple=True),
    models.ChildType(_SUFFIX_TYPE.tag, _SUFFIX_TYPE, multiple=True),
    models.ChildType(
      _AFFECTED_HISTOGRAM_TYPE.tag, _AFFECTED_HISTOGRAM_TYPE, multiple=True
    ),
  ],
)

_HISTOGRAM_SUFFIXES_LIST_TYPE = models.ObjectNodeType(
  'histogram_suffixes_list',
  alphabetization=[(_HISTOGRAM_SUFFIXES_TYPE.tag, _LOWERCASE_FN('name'))],
  extra_newlines=(2, 1, 1),
  indent=False,
  children=[
    models.ChildType(
      _HISTOGRAM_SUFFIXES_TYPE.tag, _HISTOGRAM_SUFFIXES_TYPE, multiple=True
    ),
  ],
)

_HISTOGRAM_CONFIGURATION_TYPE = models.ObjectNodeType(
  'histogram-configuration',
  alphabetization=[
    (_ENUMS_TYPE.tag, _KEEP_ORDER),
    (_HISTOGRAMS_TYPE.tag, _KEEP_ORDER),
    (_HISTOGRAM_SUFFIXES_LIST_TYPE.tag, _KEEP_ORDER),
  ],
  extra_newlines=(2, 1, 1),
  indent=False,
  children=[
    models.ChildType(_ENUMS_TYPE.tag, _ENUMS_TYPE, multiple=False),
    models.ChildType(_HISTOGRAMS_TYPE.tag, _HISTOGRAMS_TYPE, multiple=False),
    models.ChildType(
      _HISTOGRAM_SUFFIXES_LIST_TYPE.tag,
      _HISTOGRAM_SUFFIXES_LIST_TYPE,
      multiple=False,
    ),
  ],
)

HISTOGRAM_CONFIGURATION_XML_TYPE = models.DocumentType(
  _HISTOGRAM_CONFIGURATION_TYPE
)


def PrettifyTree(input_tree):
  """Parses the tree representation of the XML and return a
  pretty-printed version.

  Args:
    input_tree: A tree representation of the XML, which might take the
    form of an ET tree or minidom doc.

  Returns:
    A pretty-printed xml string, or None if the config contains errors.
  """
  histograms = HISTOGRAM_CONFIGURATION_XML_TYPE.Parse(input_tree)
  return HISTOGRAM_CONFIGURATION_XML_TYPE.PrettyPrint(histograms)