#!/usr/bin/env python3
# Copyright 2020 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Utilities for working with ConfigBundle instances more conveniently."""

import logging

from chromiumos.config.payload.config_bundle_pb2 import ConfigBundle
from chromiumos.config.payload.flat_config_pb2 import FlatConfigList

from chromiumos.config.api import device_brand_pb2
from chromiumos.config.api import design_pb2
from chromiumos.config.api.software import brand_config_pb2


def _case_equal(str1, str2):
  """Case insensitive string equals."""
  return str1.lower() == str2.lower()


def flatten_config(config: ConfigBundle) -> FlatConfigList:
  """Take a ConfigBundle and resolve all the values that are referred to by id.

  This denormalizes the ConfigBundle data to make it easier to query.

  Args:
    config: ConfigBundle instance to denormalize

  Returns
    FlatConfigList instance containing denormalized data for each device."""

  # pylint: disable=too-many-locals

  def _lookup(id_value, id_map):
    """Look up an id value in a given map, raise KeyError if not found"""
    key = id_value.value
    if not key:
      return None

    if key in id_map:
      return id_map[key]

    raise KeyError('Failed to lookup \'%s\' with value \'%s\'' %
                   (id_value.__class__.__name__.replace('Id', ''), key))

  # Break out global lists into maps from id => object
  partners = {p.id.value: p for p in config.partner_list}
  programs = {p.id.value: p for p in config.program_list}
  sw_configs = list(config.software_configs)
  brand_configs = {b.brand_id.value: b for b in config.brand_configs}

  results = FlatConfigList()
  for hw_design in config.design_list:
    logging.debug("flattening %s", hw_design.name)

    device_brands = []
    if config.device_brand_list:
      device_brands = [
          x for x in config.device_brand_list
          if x.design_id.value == hw_design.id.value
      ]

    if not device_brands:
      device_brands.append(device_brand_pb2.DeviceBrand())
    logging.debug(
        "  %d device brands: %s",
        len(device_brands),
        device_brands,
    )

    for device_brand in device_brands:
      # Brand config can be empty since platform JSON config allows it
      brand_config = brand_configs.get(device_brand.id.value,
                                       brand_config_pb2.BrandConfig())

      design_configs = hw_design.configs
      if not design_configs:
        design_configs.append(design_pb2.Design.Config())
      logging.debug(
          "  %d design configs: %s",
          len(design_configs),
          design_configs,
      )

      for hw_design_config in design_configs:
        design_id = hw_design_config.id.value
        sw_config_matches = [
            x for x in sw_configs if x.design_config_id.value == design_id
        ]
        flat_config = results.values.add()
        flat_config.hw_design.MergeFrom(hw_design)
        flat_config.hw_design_config.MergeFrom(hw_design_config)
        flat_config.hw_components.MergeFrom(config.components)
        flat_config.device_brand.MergeFrom(device_brand)
        flat_config.brand_sw_config.MergeFrom(brand_config)

        if sw_config_matches:
          flat_config.sw_config.MergeFrom(sw_config_matches[0])

        # Sometimes programs are a little slow to get properly added, so let's
        # not fail completely if they're not there, we'll just leave it empty
        # for now.
        try:
          flat_config.program.MergeFrom(_lookup(hw_design.program_id, programs))
        except KeyError:
          logging.warning(
              "program '%s' doesn't seem to be defined (bad config?)",
              hw_design.program_id.value)

        # We expect program_id to be defined above, but odm/oem is less consistently set
        if hw_design.odm_id.value:
          flat_config.odm.MergeFrom(_lookup(hw_design.odm_id, partners))

        if device_brand.oem_id.value:
          flat_config.oem.MergeFrom(_lookup(device_brand.oem_id, partners))

  logging.debug("  created %d flattened entries", len(results.values))
  return results


def find_partner(bundle: ConfigBundle, name: str, create=False):
  """Search for a partner with the given name (case insensitive).

  Args:
    bundle: config_bundle instance to search
    name: partner name to search for
    create: if partner isn't found, return a newly created one

  Returns:
    existing Partner if found, otherwise a newly created one or None
  """

  for partner in bundle.partner_list:
    if _case_equal(partner.name, name):
      return partner

  if create:
    partner = bundle.partner_list.add()
    partner.id.value = name
    partner.name = name
    return partner
  return None


def find_program(bundle: ConfigBundle, name: str, create=False):
  """Search for a program with the given name (case insensitive).

  Args:
    bundle: config_bundle instance to search
    name: program name to search for
    create: if program isn't found, return a newly created one

  Returns:
    existing Program if found, otherwise a newly created one or None
  """

  for program in bundle.program_list:
    if _case_equal(program.name, name):
      return program

  if create:
    program = bundle.program_list.add()
    program.id.value = name
    program.name = name
    return program
  return None


def find_component(bundle: ConfigBundle, id_value: str, create=False):
  """Search for a component with the given id.

  Args:
     bundle: ConfigBundle instance to search
     id_value: Value for Component.Id.Value to search for
     create: If true, return newly created component if one isn't found.

  Returns:
     existing Component if found, otherwise a newly create one, else None
  """

  for component in bundle.components:
    if _case_equal(component.id.value, id_value):
      return component

  if create:
    component = bundle.components.add()
    component.id.value = id_value
    return component
  return None