# -*-python-*-
#
# Copyright (C) 1999-2023 The ViewCVS Group. All Rights Reserved.
#
# By using this file, you agree to the terms and conditions set forth in
# the LICENSE.html file which can be found at the top level of the ViewVC
# distribution or at http://viewvc.org/license-1.html.
#
# For more information, visit http://viewvc.org/
#
# -----------------------------------------------------------------------
#
# config.py: configuration utilities
#
# -----------------------------------------------------------------------

import sys
import os
import configparser
import fnmatch
import copy


#########################################################################
#
# CONFIGURATION
# -------------
#
# There are three forms of configuration:
#
#    1. edit the viewvc.conf created by the viewvc-install(er)
#    2. as (1), but delete all unchanged entries from viewvc.conf
#    3. do not use viewvc.conf and just edit the defaults in this file
#
# Most users will want to use (1), but there are slight speed advantages
# to the other two options. Note that viewvc.conf values are a bit easier
# to work with since it is raw text, rather than python literal values.
#
#
# A WORD ABOUT OPTION LAYERING/OVERRIDES
# --------------------------------------
#
# ViewVC has three "layers" of configuration options:
#
#    1. base configuration options - very basic configuration bits
#       found in sections like 'general', 'options', etc.
#    2. vhost overrides - these options overlay/override the base
#       configuration on a per-vhost basis.
#    3. root overrides - these options overlay/override the base
#       configuration and vhost overrides on a per-root basis.
#
# Here's a diagram of the valid overlays/overrides:
#
#         PER-ROOT          PER-VHOST            BASE
#
#                         ,-----------.     ,-----------.
#                         | vhost-*|  |     |           |
#                         |  general  | --> |  general  |
#                         |           |     |           |
#                         `-----------'     `-----------'
#       ,-----------.     ,-----------.     ,-----------.
#       |  root-*|  |     | vhost-*|  |     |           |
#       |  options  | --> |  options  | --> |  options  |
#       |           |     |           |     |           |
#       `-----------'     `-----------'     `-----------'
#       ,-----------.     ,-----------.     ,-----------.
#       |  root-*|  |     | vhost-*|  |     |           |
#       | templates | --> | templates | --> | templates |
#       |           |     |           |     |           |
#       `-----------'     `-----------'     `-----------'
#       ,-----------.     ,-----------.     ,-----------.
#       |  root-*|  |     | vhost-*|  |     |           |
#       | utilities | --> | utilities | --> | utilities |
#       |           |     |           |     |           |
#       `-----------'     `-----------'     `-----------'
#                         ,-----------.     ,-----------.
#                         | vhost-*|  |     |           |
#                         |   cvsdb   | --> |   cvsdb   |
#                         |           |     |           |
#                         `-----------'     `-----------'
#       ,-----------.     ,-----------.     ,-----------.
#       |  root-*|  |     | vhost-*|  |     |           |
#       |  authz-*  | --> |  authz-*  | --> |  authz-*  |
#       |           |     |           |     |           |
#       `-----------'     `-----------'     `-----------'
#                                           ,-----------.
#                                           |           |
#                                           |  vhosts   |
#                                           |           |
#                                           `-----------'
#                                           ,-----------.
#                                           |           |
#                                           |   query   |
#                                           |           |
#                                           `-----------'
#
# ### TODO:  Figure out what this all means for the 'kv' stuff.
#
#########################################################################


class Config:
    _base_sections = (
        # Base configuration sections.
        "authz-*",
        "cvsdb",
        "general",
        "options",
        "query",
        "templates",
        "utilities",
    )
    _force_multi_value = (
        # Configuration values with multiple, comma-separated values.
        "allowed_views",
        "binary_mime_types",
        "dir_ignored_files",
        "custom_log_formatting",
        "cvs_roots",
        "kv_files",
        "languages",
        "mime_types_files",
        "root_parents",
        "svn_roots",
        "renamed_roots",
    )
    _allowed_overrides = {
        # Mapping of override types to allowed overridable sections.
        "vhost": (
            "authz-*",
            "cvsdb",
            "general",
            "options",
            "templates",
            "utilities",
        ),
        "root": (
            "authz-*",
            "options",
            "templates",
            "utilities",
        ),
    }

    def __init__(self):
        self.root_options_overlayed = 0
        for section in self._base_sections:
            if section[-1] == "*":
                continue
            setattr(self, section, _sub_config())

    def copy(self):
        return copy.deepcopy(self)

    def load_config(self, pathname, vhost=None):
        """Load the configuration file at PATHNAME, applying configuration
        settings there as overrides to the built-in default values.  If
        VHOST is provided, also process the configuration overrides
        specific to that virtual host."""

        class CustomParser(configparser.ConfigParser):
            """A ConfigParser class which prevents deepcopying self.
            We can treat an instances of this class as an immutable
            where we'll see it out of Config.load_config()."""

            def __deepcopy__(self, memo):
                return self

        self.conf_path = os.path.isfile(pathname) and pathname or None
        self.base = os.path.dirname(pathname)
        self.parser = CustomParser()
        self.parser.optionxform = lambda x: x  # don't case-normalize option names.
        self.parser.read(self.conf_path or [])

        for section in self.parser.sections():
            if self._is_allowed_section(section, self._base_sections):
                self._process_section(self.parser, section, section)

        if vhost and self.parser.has_section("vhosts"):
            self._process_vhost(self.parser, vhost)

    def load_kv_files(self, language):
        """Process the key/value (kv) files specified in the
        configuration, merging their values into the configuration as
        dotted heirarchical items."""

        kv = _sub_config()

        for fname in self.general.kv_files:
            if fname[0] == "[":
                idx = fname.index("]")
                parts = fname[1:idx].split(".")
                fname = fname[(idx + 1) :].strip()
            else:
                parts = []
            fname = fname.replace("%lang%", language)

            parser = configparser.ConfigParser()
            parser.optionxform = lambda x: x  # don't case-normalize option names.
            parser.read(os.path.join(self.base, fname))
            for section in parser.sections():
                for option in parser.options(section):
                    full_name = parts + [section]
                    ob = kv
                    for name in full_name:
                        try:
                            ob = getattr(ob, name)
                        except AttributeError:
                            c = _sub_config()
                            setattr(ob, name, c)
                            ob = c
                    setattr(ob, option, parser.get(section, option))

        return kv

    def path(self, path):
        """Return PATH relative to the config file directory."""
        return os.path.join(self.base, path)

    def _process_section(self, parser, section, subcfg_name):
        if not hasattr(self, subcfg_name):
            setattr(self, subcfg_name, _sub_config())
        sc = getattr(self, subcfg_name)

        for opt in parser.options(section):
            value = parser.get(section, opt)
            if opt in self._force_multi_value:
                value = [x.strip() for x in [_f for _f in value.split(",") if _f]]
            else:
                try:
                    value = int(value)
                except ValueError:
                    pass

            # FIXME: This feels like unnecessary depth of knowledge for a
            # semi-generic configuration object.
            if opt == "cvs_roots" or opt == "svn_roots" or opt == "renamed_roots":
                value = _parse_roots(opt, value)

            setattr(sc, opt, value)

    def _is_allowed_section(self, section, allowed_sections):
        """Return 1 iff SECTION is an allowed section, defined as being
        explicitly present in the ALLOWED_SECTIONS list or present in the
        form 'someprefix-*' in that list."""

        for allowed_section in allowed_sections:
            if allowed_section[-1] == "*":
                if _startswith(section, allowed_section[:-1]):
                    return 1
            elif allowed_section == section:
                return 1
        return 0

    def _is_allowed_override(self, sectype, secspec, section):
        """Test if SECTION is an allowed override section for sections of
        type SECTYPE ('vhosts' or 'root', currently) and type-specifier
        SECSPEC (a rootname or vhostname, currently).  If it is, return
        the overridden base section name.  If it's not an override section
        at all, return None.  And if it's an override section but not an
        allowed one, raise IllegalOverrideSection."""

        cv = "%s-%s|" % (sectype, secspec)
        lcv = len(cv)
        if section[:lcv] != cv:
            return None
        base_section = section[lcv:]
        if self._is_allowed_section(base_section, self._allowed_overrides[sectype]):
            return base_section
        raise IllegalOverrideSection(sectype, section)

    def _process_vhost(self, parser, vhost):
        # Find a vhost name for this VHOST, if any (else, we've nothing to do).
        canon_vhost = self._find_canon_vhost(parser, vhost)
        if not canon_vhost:
            return

        # Overlay any option sections associated with this vhost name.
        for section in parser.sections():
            base_section = self._is_allowed_override("vhost", canon_vhost, section)
            if base_section:
                self._process_section(parser, section, base_section)

    def _find_canon_vhost(self, parser, vhost):
        vhost = vhost.lower().split(":")[0]  # lower-case, no port
        for canon_vhost in parser.options("vhosts"):
            value = parser.get("vhosts", canon_vhost)
            patterns = map(lambda x: x.lower().strip(), filter(None, value.split(",")))
            patterns = [x.lower().strip() for x in [_f for _f in value.split(",") if _f]]
            for pat in patterns:
                if fnmatch.fnmatchcase(vhost, pat):
                    return canon_vhost

        return None

    def overlay_root_options(self, rootname):
        """Overlay per-root options for ROOTNAME atop the existing option
        set.  This is a destructive change to the configuration."""

        did_overlay = 0

        if not self.conf_path:
            return

        for section in self.parser.sections():
            base_section = self._is_allowed_override("root", rootname, section)
            if base_section:
                # We can currently only deal with root overlays happening
                # once, so check that we've not yet done any overlaying of
                # per-root options.
                assert self.root_options_overlayed == 0
                self._process_section(self.parser, section, base_section)
                did_overlay = 1

        # If we actually did any overlaying, remember this fact so we
        # don't do it again later.
        if did_overlay:
            self.root_options_overlayed = 1

    def get_authorizer_and_params_hack(self, rootname):
        """Return a 2-tuple containing the name and parameters of the
        authorizer configured for use with ROOTNAME.

        ### FIXME: This whole thing is a hack caused by our not being able
        ### to non-destructively overlay root options when trying to do
        ### something like a root listing (which might need to get
        ### different authorizer bits for each and every root in the list).
        ### Until we have a good way to do that, we expose this function,
        ### which assumes that base and per-vhost configuration has been
        ### absorbed into this object and that per-root options have *not*
        ### been overlayed.  See issue #371."""

        # We assume that per-root options have *not* been overlayed.
        assert self.root_options_overlayed == 0

        if not self.conf_path:
            return None, {}

        # Figure out the authorizer by searching first for a per-root
        # override, then falling back to the base/vhost configuration.
        authorizer = None
        root_options_section = "root-%s|options" % (rootname)
        if self.parser.has_section(root_options_section) and self.parser.has_option(
            root_options_section, "authorizer"
        ):
            authorizer = self.parser.get(root_options_section, "authorizer")
        if not authorizer:
            authorizer = self.options.authorizer

        # No authorizer?  Get outta here.
        if not authorizer:
            return None, {}

        # Dig up the parameters for the authorizer, starting with the
        # base/vhost items, then overlaying any root-specific ones we find.
        params = {}
        authz_section = "authz-%s" % (authorizer)
        if hasattr(self, authz_section):
            sub_config = getattr(self, authz_section)
            for attr in dir(sub_config):
                params[attr] = getattr(sub_config, attr)
        root_authz_section = "root-%s|authz-%s" % (rootname, authorizer)
        for section in self.parser.sections():
            if section == root_authz_section:
                for key, value in self.parser.items():
                    params[key] = value
        return authorizer, params

    def get_authorizer_params(self, authorizer=None):
        """Return a dictionary of parameter names and values which belong
        to the configured authorizer (or AUTHORIZER, if provided)."""
        params = {}
        if authorizer is None:
            authorizer = self.options.authorizer
        if authorizer:
            authz_section = "authz-%s" % (self.options.authorizer)
            if hasattr(self, authz_section):
                sub_config = getattr(self, authz_section)
                for attr in dir(sub_config):
                    params[attr] = getattr(sub_config, attr)
        return params

    def set_defaults(self):
        "Set some default values in the configuration."

        self.general.cvs_roots = {}
        self.general.svn_roots = {}
        self.general.renamed_roots = {}
        self.general.root_parents = []
        self.general.default_root = ""
        self.general.mime_types_files = ["mimetypes.conf"]
        self.general.address = ""
        self.general.kv_files = []
        self.general.languages = ["en-us"]

        self.utilities.rcs_dir = ""
        if sys.platform == "win32":
            self.utilities.cvsnt = "cvs"
        else:
            self.utilities.cvsnt = None
        self.utilities.diff = ""
        self.utilities.max_context = 10000
        self.utilities.cvsgraph = ""

        self.options.root_path_locale = None
        self.options.root_as_url_component = 1
        self.options.allowed_views = ["annotate", "diff", "markup", "roots"]
        self.options.authorizer = None
        self.options.mangle_email_addresses = 0
        self.options.custom_log_formatting = []
        self.options.default_file_view = "log"
        self.options.allow_mojibake = 0
        self.options.binary_mime_types = []
        self.options.dir_ignored_files = []
        self.options.http_expiration_time = 600
        self.options.generate_etags = 1
        self.options.svn_ignore_mimetype = 0
        self.options.svn_config_dir = None
        self.options.max_filesize_kbytes = 512
        self.options.use_rcsparse = 0
        self.options.sort_by = "file"
        self.options.sort_group_dirs = 1
        self.options.hide_attic = 1
        self.options.hide_errorful_entries = 0
        self.options.log_sort = "date"
        self.options.diff_format = "h"
        self.options.hide_cvsroot = 1
        self.options.hr_breakable = 1
        self.options.hr_funout = 1
        self.options.hr_ignore_white = 0
        self.options.hr_ignore_keyword_subst = 1
        self.options.hr_intraline = 0
        self.options.allow_compress = 0
        self.options.template_dir = "templates/default"
        self.options.docroot = None
        self.options.show_subdir_lastmod = 0
        self.options.show_roots_lastmod = 0
        self.options.show_logs = 1
        self.options.show_log_in_markup = 1
        self.options.cross_copies = 1
        self.options.use_localtime = 0
        self.options.iso8601_timestamps = 0
        self.options.short_log_len = 80
        self.options.enable_syntax_coloration = 1
        self.options.tabsize = 8
        self.options.detect_encoding = 0
        self.options.default_encoding = None
        self.options.use_cvsgraph = 0
        self.options.cvsgraph_conf = "cvsgraph.conf"
        self.options.allowed_cvsgraph_useropts = []
        self.options.use_re_search = 0
        self.options.dir_pagesize = 0
        self.options.log_pagesize = 0
        self.options.log_pagesextra = 3
        self.options.limit_changes = 100
        self.options.stacktraces = 0

        self.templates.diff = None
        self.templates.directory = None
        self.templates.error = None
        self.templates.file = None
        self.templates.graph = None
        self.templates.log = None
        self.templates.query_form = None
        self.templates.query_results = None
        self.templates.roots = None

        self.cvsdb.enabled = 0
        self.cvsdb.host = ""
        self.cvsdb.port = 3306
        self.cvsdb.database_name = ""
        self.cvsdb.user = ""
        self.cvsdb.passwd = ""
        self.cvsdb.readonly_user = ""
        self.cvsdb.readonly_passwd = ""
        self.cvsdb.row_limit = 1000
        self.cvsdb.rss_row_limit = 100
        self.cvsdb.check_database_for_root = 0


def _startswith(somestr, substr):
    return somestr[: len(substr)] == substr


def _parse_roots(config_name, config_value):
    roots = {}
    for root in config_value:
        try:
            name, path = root.split(":", 1)
        except Exception:
            raise MalformedRoot(config_name, root)
        roots[name.strip()] = path.strip()
    return roots


class ViewVCConfigurationError(Exception):
    pass


class IllegalOverrideSection(ViewVCConfigurationError):
    def __init__(self, override_type, section_name):
        self.section_name = section_name
        self.override_type = override_type

    def __str__(self):
        return "malformed configuration: illegal %s override section: %s" % (
            self.override_type,
            self.section_name,
        )


class MalformedRoot(ViewVCConfigurationError):
    def __init__(self, config_name, value_given):
        Exception.__init__(self, config_name, value_given)
        self.config_name = config_name
        self.value_given = value_given

    def __str__(self):
        return "malformed configuration: '%s' uses invalid syntax: %s" % (
            self.config_name,
            self.value_given,
        )


class _sub_config:
    pass
