# -*- coding: utf-8 -*-
# Copyright (C) 2012 Anaconda, Inc
# SPDX-License-Identifier: BSD-3-Clause
from __future__ import absolute_import, division, print_function, unicode_literals

from collections.abc import Mapping, Sequence
import json
from logging import getLogger
import os
from os.path import isfile, join
import sys
from textwrap import wrap

from .. import CondaError
from ..auxlib.entity import EntityEncoder
from .._vendor.toolz import concat, groupby
from ..base.constants import (ChannelPriority, DepsModifier, PathConflict, SafetyChecks,
                              UpdateModifier, SatSolverChoice, ExperimentalSolverChoice)
from ..base.context import context, sys_rc_path, user_rc_path
from ..common.compat import isiterable
from ..common.configuration import pretty_list, pretty_map
from ..common.io import timeout
from ..common.serialize import yaml, yaml_round_trip_dump, yaml_round_trip_load


def execute(args, parser):
    from ..exceptions import CouldntParseError
    try:
        execute_config(args, parser)
    except (CouldntParseError, NotImplementedError) as e:
        raise CondaError(e)


def format_dict(d):
    lines = []
    for k, v in d.items():
        if isinstance(v, Mapping):
            if v:
                lines.append("%s:" % k)
                lines.append(pretty_map(v))
            else:
                lines.append("%s: {}" % k)
        elif isiterable(v):
            if v:
                lines.append("%s:" % k)
                lines.append(pretty_list(v))
            else:
                lines.append("%s: []" % k)
        else:
            lines.append("%s: %s" % (k, v if v is not None else "None"))
    return lines


def parameter_description_builder(name):
    builder = []
    details = context.describe_parameter(name)
    aliases = details['aliases']
    string_delimiter = details.get('string_delimiter')
    element_types = details['element_types']
    default_value_str = json.dumps(details['default_value'], cls=EntityEncoder)

    if details['parameter_type'] == 'primitive':
        builder.append("%s (%s)" % (name, ', '.join(sorted(set(et for et in element_types)))))
    else:
        builder.append("%s (%s: %s)" % (name, details['parameter_type'],
                                        ', '.join(sorted(set(et for et in element_types)))))

    if aliases:
        builder.append("  aliases: %s" % ', '.join(aliases))
    if string_delimiter:
        builder.append("  env var string delimiter: '%s'" % string_delimiter)

    builder.extend('  ' + line for line in wrap(details['description'], 70))

    builder.append('')
    builder = ['# ' + line for line in builder]

    builder.extend(yaml_round_trip_dump({name: json.loads(default_value_str)}).strip().split('\n'))

    builder = ['# ' + line for line in builder]
    builder.append('')
    return builder


def describe_all_parameters():
    builder = []
    skip_categories = ('CLI-only', 'Hidden and Undocumented')
    for category, parameter_names in context.category_map.items():
        if category in skip_categories:
            continue
        builder.append('# ######################################################')
        builder.append('# ## {:^48} ##'.format(category))
        builder.append('# ######################################################')
        builder.append('')
        builder.extend(concat(parameter_description_builder(name)
                              for name in parameter_names))
        builder.append('')
    return '\n'.join(builder)


def print_config_item(key, value):
    stdout_write = getLogger("conda.stdout").info
    if isinstance(value, (dict,)):
        for k, v in value.items():
            print_config_item(key + "." + k, v)
    elif isinstance(value, (bool, int, str)):
        stdout_write(" ".join(("--set", key, str(value))))
    elif isinstance(value, (list, tuple)):
        # Note, since `conda config --add` prepends, print `--add` commands in
        # reverse order (using repr), so that entering them in this order will
        # recreate the same file.
        numitems = len(value)
        for q, item in enumerate(reversed(value)):
            if key == "channels" and q in (0, numitems-1):
                stdout_write(" ".join((
                    "--add", key, repr(item),
                    "  # lowest priority" if q == 0 else "  # highest priority"
                )))
            else:
                stdout_write(" ".join(("--add", key, repr(item))))


def execute_config(args, parser):
    stdout_write = getLogger("conda.stdout").info
    stderr_write = getLogger("conda.stderr").info
    json_warnings = []
    json_get = {}

    if args.show_sources:
        if context.json:
            stdout_write(json.dumps(
                context.collect_all(), sort_keys=True, indent=2, separators=(',', ': '),
                cls=EntityEncoder
            ))
        else:
            lines = []
            for source, reprs in context.collect_all().items():
                lines.append("==> %s <==" % source)
                lines.extend(format_dict(reprs))
                lines.append('')
            stdout_write('\n'.join(lines))
        return

    if args.show is not None:
        if args.show:
            paramater_names = args.show
            all_names = context.list_parameters()
            not_params = set(paramater_names) - set(all_names)
            if not_params:
                from ..exceptions import ArgumentError
                from ..common.io import dashlist
                raise ArgumentError("Invalid configuration parameters: %s" % dashlist(not_params))
        else:
            paramater_names = context.list_parameters()

        d = {key: getattr(context, key) for key in paramater_names}
        if context.json:
            stdout_write(json.dumps(
                d, sort_keys=True, indent=2, separators=(',', ': '), cls=EntityEncoder
            ))
        else:
            # Add in custom formatting
            if 'custom_channels' in d:
                d['custom_channels'] = {
                    channel.name: "%s://%s" % (channel.scheme, channel.location)
                    for channel in d['custom_channels'].values()
                }
            if 'custom_multichannels' in d:
                from ..common.io import dashlist
                d['custom_multichannels'] = {
                    multichannel_name: dashlist(channels, indent=4)
                    for multichannel_name, channels in d['custom_multichannels'].items()
                }

            stdout_write('\n'.join(format_dict(d)))
        context.validate_configuration()
        return

    if args.describe is not None:
        if args.describe:
            paramater_names = args.describe
            all_names = context.list_parameters()
            not_params = set(paramater_names) - set(all_names)
            if not_params:
                from ..exceptions import ArgumentError
                from ..common.io import dashlist
                raise ArgumentError("Invalid configuration parameters: %s" % dashlist(not_params))
            if context.json:
                stdout_write(json.dumps(
                    [context.describe_parameter(name) for name in paramater_names],
                    sort_keys=True, indent=2, separators=(',', ': '), cls=EntityEncoder
                ))
            else:
                builder = []
                builder.extend(concat(parameter_description_builder(name)
                                      for name in paramater_names))
                stdout_write('\n'.join(builder))
        else:
            if context.json:
                skip_categories = ('CLI-only', 'Hidden and Undocumented')
                paramater_names = sorted(concat(
                    parameter_names for category, parameter_names in context.category_map.items()
                    if category not in skip_categories
                ))
                stdout_write(json.dumps(
                    [context.describe_parameter(name) for name in paramater_names],
                    sort_keys=True, indent=2, separators=(',', ': '), cls=EntityEncoder
                ))
            else:
                stdout_write(describe_all_parameters())
        return

    if args.validate:
        context.validate_all()
        return

    if args.system:
        rc_path = sys_rc_path
    elif args.env:
        if 'CONDA_PREFIX' in os.environ:
            rc_path = join(os.environ['CONDA_PREFIX'], '.condarc')
        else:
            rc_path = user_rc_path
    elif args.file:
        rc_path = args.file
    else:
        rc_path = user_rc_path

    if args.write_default:
        if isfile(rc_path):
            with open(rc_path) as fh:
                data = fh.read().strip()
            if data:
                raise CondaError("The file '%s' "
                                 "already contains configuration information.\n"
                                 "Remove the file to proceed.\n"
                                 "Use `conda config --describe` to display default configuration."
                                 % rc_path)

        with open(rc_path, 'w') as fh:
            fh.write(describe_all_parameters())
        return

    # read existing condarc
    if os.path.exists(rc_path):
        with open(rc_path, 'r') as fh:
            # round trip load required because... we need to round trip
            rc_config = yaml_round_trip_load(fh) or {}
    elif os.path.exists(sys_rc_path):
        # In case the considered rc file doesn't exist, fall back to the system rc
        with open(sys_rc_path, 'r') as fh:
            rc_config = yaml_round_trip_load(fh) or {}
    else:
        rc_config = {}

    grouped_paramaters = groupby(lambda p: context.describe_parameter(p)['parameter_type'],
                                 context.list_parameters())
    primitive_parameters = grouped_paramaters['primitive']
    sequence_parameters = grouped_paramaters['sequence']
    map_parameters = grouped_paramaters['map']
    all_parameters = primitive_parameters + sequence_parameters + map_parameters

    # Get
    if args.get is not None:
        context.validate_all()
        if args.get == []:
            args.get = sorted(rc_config.keys())

        value_not_found = object()
        for key in args.get:
            key_parts = key.split(".")

            if key_parts[0] not in all_parameters:
                message = "unknown key %s" % key_parts[0]
                if not context.json:
                    stderr_write(message)
                else:
                    json_warnings.append(message)
                continue

            remaining_rc_config = rc_config
            for k in key_parts:
                if k in remaining_rc_config:
                    remaining_rc_config = remaining_rc_config[k]
                else:
                    remaining_rc_config = value_not_found
                    break

            if remaining_rc_config is value_not_found:
                pass
            elif context.json:
                json_get[key] = remaining_rc_config
            else:
                print_config_item(key, remaining_rc_config)

    if args.stdin:
        content = timeout(5, sys.stdin.read)
        if not content:
            return
        try:
            # round trip load required because... we need to round trip
            parsed = yaml_round_trip_load(content)
            rc_config.update(parsed)
        except Exception:  # pragma: no cover
            from ..exceptions import ParseError
            raise ParseError("invalid yaml content:\n%s" % content)

    # prepend, append, add
    for arg, prepend in zip((args.prepend, args.append), (True, False)):
        for key, item in arg:
            key, subkey = key.split('.', 1) if '.' in key else (key, None)
            if key == 'channels' and key not in rc_config:
                rc_config[key] = ['defaults']
            if key in sequence_parameters:
                arglist = rc_config.setdefault(key, [])
            elif key in map_parameters:
                arglist = rc_config.setdefault(key, {}).setdefault(subkey, [])
            else:
                from ..exceptions import CondaValueError
                raise CondaValueError("Key '%s' is not a known sequence parameter." % key)
            if not (isinstance(arglist, Sequence) and not
                    isinstance(arglist, str)):
                from ..exceptions import CouldntParseError
                bad = rc_config[key].__class__.__name__
                raise CouldntParseError("key %r should be a list, not %s." % (key, bad))
            if item in arglist:
                message_key = key + "." + subkey if subkey is not None else key
                # Right now, all list keys should not contain duplicates
                message = "Warning: '%s' already in '%s' list, moving to the %s" % (
                    item, message_key, "top" if prepend else "bottom")
                if subkey is None:
                    arglist = rc_config[key] = [p for p in arglist if p != item]
                else:
                    arglist = rc_config[key][subkey] = [p for p in arglist if p != item]
                if not context.json:
                    stderr_write(message)
                else:
                    json_warnings.append(message)
            arglist.insert(0 if prepend else len(arglist), item)

    # Set
    for key, item in args.set:
        key, subkey = key.split('.', 1) if '.' in key else (key, None)
        if key in primitive_parameters:
            value = context.typify_parameter(key, item, "--set parameter")
            rc_config[key] = value
        elif key in map_parameters:
            argmap = rc_config.setdefault(key, {})
            argmap[subkey] = item
        else:
            from ..exceptions import CondaValueError
            raise CondaValueError("Key '%s' is not a known primitive parameter." % key)

    # Remove
    for key, item in args.remove:
        key, subkey = key.split('.', 1) if '.' in key else (key, None)
        if key not in rc_config:
            if key != 'channels':
                from ..exceptions import CondaKeyError
                raise CondaKeyError(key, "key %r is not in the config file" % key)
            rc_config[key] = ['defaults']
        if item not in rc_config[key]:
            from ..exceptions import CondaKeyError
            raise CondaKeyError(key, "%r is not in the %r key of the config file" %
                                (item, key))
        rc_config[key] = [i for i in rc_config[key] if i != item]

    # Remove Key
    for key, in args.remove_key:
        key, subkey = key.split('.', 1) if '.' in key else (key, None)
        if key not in rc_config:
            from ..exceptions import CondaKeyError
            raise CondaKeyError(key, "key %r is not in the config file" %
                                key)
        del rc_config[key]

    # config.rc_keys
    if not args.get:

        # Add representers for enums.
        # Because a representer cannot be added for the base Enum class (it must be added for
        # each specific Enum subclass - and because of import rules), I don't know of a better
        # location to do this.
        def enum_representer(dumper, data):
            return dumper.represent_str(str(data))

        yaml.representer.RoundTripRepresenter.add_representer(SafetyChecks, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(PathConflict, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(DepsModifier, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(UpdateModifier, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(ChannelPriority, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(SatSolverChoice, enum_representer)
        yaml.representer.RoundTripRepresenter.add_representer(
            ExperimentalSolverChoice, enum_representer
        )

        try:
            with open(rc_path, 'w') as rc:
                rc.write(yaml_round_trip_dump(rc_config))
        except (IOError, OSError) as e:
            raise CondaError('Cannot write to condarc file at %s\n'
                             'Caused by %r' % (rc_path, e))

    if context.json:
        from .common import stdout_json_success
        stdout_json_success(
            rc_path=rc_path,
            warnings=json_warnings,
            get=json_get
        )
    return