#!/usr/bin/env python
# -*- coding: utf-8 -*-


# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <https://gnu.org/licenses/>.


from __future__ import print_function
import os
import sys
import copy
import lxml.etree


# HACK: define cmp in python3
if sys.version_info[0] == 3:
    def cmp(a, b):
        return (a > b) - (a < b)


def get_variants_dtd(logger=None):
    """
    Find the DTD for variants file. First look into the system directory, and
    fall back to local directory.
    """
    variants_dtd = "/usr/share/pungi/variants.dtd"
    if not os.path.isfile(variants_dtd):
        devel_variants_dtd = os.path.normpath(os.path.realpath(
            os.path.join(os.path.dirname(__file__), "..", "..", "share", "variants.dtd")))
        msg = "Variants DTD not found: %s" % variants_dtd
        if os.path.isfile(devel_variants_dtd):
            if logger:
                logger.warning("%s", msg)
                logger.warning("Using alternative DTD: %s", devel_variants_dtd)
            variants_dtd = devel_variants_dtd
        else:
            raise RuntimeError(msg)
    return variants_dtd


class VariantsXmlParser(object):
    def __init__(self, file_obj, tree_arches=None, tree_variants=None, logger=None):
        self.tree = lxml.etree.parse(file_obj)
        with open(get_variants_dtd(logger), 'r') as f:
            self.dtd = lxml.etree.DTD(f)
        self.addons = {}
        self.layered_products = {}
        self.tree_arches = tree_arches
        self.tree_variants = tree_variants
        self.logger = logger
        self.validate()

    def _is_true(self, value):
        if value == "true":
            return True
        if value == "false":
            return False
        raise ValueError("Invalid boolean value in variants XML: %s" % value)

    def validate(self):
        if not self.dtd.validate(self.tree):
            errors = [str(i) for i in self.dtd.error_log.filter_from_errors()]
            raise ValueError("Variants XML doesn't validate:\n%s" % "\n".join(errors))

    def parse_variant_node(self, variant_node, parent=None):
        variant_dict = {
            "id": str(variant_node.attrib["id"]),
            "name": str(variant_node.attrib["name"]),
            "type": str(variant_node.attrib["type"]),
            "arches": [str(i) for i in variant_node.xpath("arches/arch/text()")],
            "groups": [],
            "environments": [],
            "buildinstallpackages": [],
            "is_empty": bool(variant_node.attrib.get("is_empty", False)),
            "parent": parent,
        }
        if self.tree_arches:
            variant_dict["arches"] = [i for i in variant_dict["arches"] if i in self.tree_arches]
        if not variant_dict["arches"]:
            if self.logger:
                self.logger.info('Excluding variant %s: all its arches are filtered.' % variant_dict['id'])
            return None

        for grouplist_node in variant_node.xpath("groups"):
            for group_node in grouplist_node.xpath("group"):
                group = {
                    "name": str(group_node.text),
                    "glob": self._is_true(group_node.attrib.get("glob", "false")),
                    "default": None,
                    "uservisible": None,
                }

                default = group_node.attrib.get("default")
                if default is not None:
                    group["default"] = self._is_true(default)

                uservisible = group_node.attrib.get("uservisible")
                if uservisible is not None:
                    group["uservisible"] = self._is_true(uservisible)

                variant_dict["groups"].append(group)

        for environments_node in variant_node.xpath("environments"):
            for environment_node in environments_node.xpath("environment"):
                environment = {
                    "name": str(environment_node.text),
                    "display_order": None,
                }

                display_order = environment_node.attrib.get("display_order")
                if display_order is not None:
                    environment["display_order"] = int(display_order)

                variant_dict["environments"].append(environment)

        for buildinstallpackages_node in variant_node.xpath("buildinstallpackages"):
            for package_node in buildinstallpackages_node.xpath("package"):
                variant_dict["buildinstallpackages"].append(package_node.text)

        variant = Variant(**variant_dict)
        if variant.type == "layered-product":
            release_node = variant_node.xpath("release")[0]
            variant.release_name = str(release_node.attrib["name"])
            variant.release_version = str(release_node.attrib["version"])
            variant.release_short = str(release_node.attrib["short"])

        contains_optional = False
        for child_node in variant_node.xpath("variants/variant"):
            child_variant = self.parse_variant_node(child_node, variant)
            if not self.add_child(child_variant, variant):
                continue
            if child_variant.type == "optional":
                contains_optional = True

        has_optional = self._is_true(variant_node.attrib.get("has_optional", "false"))
        if has_optional and not contains_optional:
            optional = Variant(id="optional", name="optional", type="optional",
                               arches=variant.arches, groups=[], parent=variant)
            self.add_child(optional, variant)

        for ref in variant_node.xpath("variants/ref/@id"):
            try:
                child_variant = self.parse_variant_node(self.addons[ref], variant)
            except KeyError:
                raise RuntimeError("Variant %s references non-existing variant %s"
                                   % (variant.uid, ref))
            self.add_child(child_variant, variant)

# XXX: top-level optional
#    for ref in variant_node.xpath("variants/ref/@id"):
#        variant["variants"].append(copy.deepcopy(addons[ref]))

        return variant

    def _is_excluded(self, variant):
        if self.tree_variants and variant.uid not in self.tree_variants:
            if self.logger:
                self.logger.info('Excluding variant %s: filtered by configuration.' % variant)
            return True
        return False

    def add_child(self, child, parent):
        if not child or self._is_excluded(child):
            return None
        parent.add_variant(child)
        return child

    def parse(self):
        # we allow top-level addon definitions which can be referenced in variants
        for variant_node in self.tree.xpath("/variants/variant[@type='addon']"):
            variant_id = str(variant_node.attrib["id"])
            self.addons[variant_id] = variant_node

        for variant_node in self.tree.xpath("/variants/variant[@type='layered-product']"):
            variant_id = str(variant_node.attrib["id"])
            self.addons[variant_id] = variant_node

        result = {}
        for variant_node in self.tree.xpath("/variants/variant[@type='variant']"):
            variant = self.parse_variant_node(variant_node)
            if not variant or self._is_excluded(variant):
                continue
            result[variant.id] = variant

        for variant_node in self.tree.xpath("/variants/variant[not(@type='variant' or @type='addon' or @type='layered-product')]"):
            raise RuntimeError("Invalid variant type at the top-level: %s" % variant_node.attrib["type"])

        return result


class Variant(object):
    def __init__(self, id, name, type, arches, groups, environments=None,
                 buildinstallpackages=None, is_empty=False, parent=None):

        environments = environments or []
        buildinstallpackages = buildinstallpackages or []

        self.id = id
        self.name = name
        self.type = type
        self.arches = sorted(copy.deepcopy(arches))
        self.groups = sorted(copy.deepcopy(groups), lambda x, y: cmp(x["name"], y["name"]))
        self.environments = sorted(copy.deepcopy(environments), lambda x, y: cmp(x["name"], y["name"]))
        self.buildinstallpackages = sorted(buildinstallpackages)
        self.variants = {}
        self.parent = parent
        self.is_empty = is_empty

    def __getitem__(self, name):
        return self.variants[name]

    def __str__(self):
        return self.uid

    def __repr__(self):
        return 'Variant(id="{0.id}", name="{0.name}", type="{0.type}", parent={0.parent})'.format(self)

    def __cmp__(self, other):
        # variant < addon, layered-product < optional
        if self.type == other.type:
            return cmp(self.uid, other.uid)
        if self.type == "variant":
            return -1
        if other.type == "variant":
            return 1
        if self.type == "optional":
            return 1
        if other.type == "optional":
            return -1
        return cmp(self.uid, other.uid)

    @property
    def uid(self):
        if self.parent:
            return "%s-%s" % (self.parent, self.id)
        return self.id

    def add_variant(self, variant):
        """Add a variant object to the child variant list."""
        if variant.id in self.variants:
            return
        if self.type != "variant":
            raise RuntimeError("Only 'variant' can contain another variants.")
        if variant.id == self.id:
            # due to os/<variant.id> path -- addon id would conflict with parent variant id
            raise RuntimeError("Child variant id must be different than parent variant id: %s" % variant.id)
        # sometimes an addon or layered product can be part of multiple variants with different set of arches
        arches = sorted(set(self.arches).intersection(set(variant.arches)))
        if self.arches and not arches:
            raise RuntimeError("%s: arch list %s does not intersect with parent arch list: %s" % (variant, variant.arches, self.arches))
        variant.arches = arches
        self.variants[variant.id] = variant
        variant.parent = self

    def get_groups(self, arch=None, types=None, recursive=False):
        """Return list of groups, default types is ["self"]"""

        types = types or ["self"]
        result = copy.deepcopy(self.groups)
        for variant in self.get_variants(arch=arch, types=types, recursive=recursive):
            if variant == self:
                # XXX
                continue
            for group in variant.get_groups(arch=arch, types=types, recursive=recursive):
                if group not in result:
                    result.append(group)
        return result

    def get_variants(self, arch=None, types=None, recursive=False):
        """
        Return all variants of given arch and types.

        Supported variant types:
            self     - include the top-level ("self") variant as well
            addon
            variant
            optional
        """
        types = types or []
        result = []

        if arch and arch not in self.arches + ["src"]:
            return result

        if "self" in types:
            result.append(self)

        for variant in self.variants.values():
            if types and variant.type not in types:
                continue
            if arch and arch not in variant.arches + ["src"]:
                continue
            result.append(variant)
            if recursive:
                result.extend(variant.get_variants(types=[i for i in types if i != "self"], recursive=True))

        return result

    def get_addons(self, arch=None):
        """Return all 'addon' child variants. No recursion."""
        return self.get_variants(arch=arch, types=["addon"], recursive=False)

    def get_layered_products(self, arch=None):
        """Return all 'layered-product' child variants. No recursion."""
        return self.get_variants(arch=arch, types=["layered-product"], recursive=False)

    def get_optional(self, arch=None):
        """Return all 'optional' child variants. No recursion."""
        return self.get_variants(arch=arch, types=["optional"], recursive=False)


def main(argv):
    import optparse

    parser = optparse.OptionParser("%prog <variants.xml>")
    opts, args = parser.parse_args(argv)

    if len(args) != 1:
        parser.error("Please provide a <variants.xml> file.")

    file_path = args[0]
    try:
        file_obj = open(file_path, "r")
    except Exception as ex:
        print(str(ex), file=sys.stderr)
        sys.exit(1)

    for top_level_variant in list(VariantsXmlParser(file_obj).parse().values()):
        for i in top_level_variant.get_variants(types=["self", "variant", "addon", "layered-product", "optional"], recursive=True):
            print("ID: %-30s NAME: %-40s TYPE: %-12s UID: %s" % (i.id, i.name, i.type, i))
            print("    ARCHES: %s" % ", ".join(sorted(i.arches)))
            for group in i.groups:
                print("    GROUP:  %(name)-40s GLOB: %(glob)-5s DEFAULT: %(default)-5s USERVISIBLE: %(uservisible)-5s" % group)
            for env in i.environments:
                print("    ENV:    %(name)-40s DISPLAY_ORDER: %(display_order)s" % env)
            print()


if __name__ == "__main__":
    main(sys.argv[1:])