#!/usr/bin/python
#
# -*- coding: utf-8 -*-
#
# Copyright (C) 2008, TUBITAK/UEKAE
#
# 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; either version 2 of the License, or (at your option)
# any later version.
#
# Please read the COPYING file.
#

import sys

import pisi
import pisi.dependency as dependency
from pisi.graph import CycleException
import piksemel

class SourceDB:
    def __init__(self, index):

        self.__source_nodes = {}
        self.__pkgstosrc = {}

        doc = piksemel.parse(index)
        self.__source_nodes, self.__pkgstosrc = self.__generate_sources(doc)

    def __generate_sources(self, doc):
        sources = {}
        pkgstosrc = {}

        for spec in doc.tags("SpecFile"):
            src_name = spec.getTag("Source").getTagData("Name")
            sources[src_name] = spec.toString()
            for package in spec.tags("Package"):
                pkgstosrc[package.getTagData("Name")] = src_name
        
        return sources, pkgstosrc

    def has_spec(self, name):
        return self.__source_nodes.has_key(name)

    def get_spec(self, name):
        src = self.__source_nodes[name]
        spec = pisi.specfile.SpecFile()
        spec.parse(src)
        return spec

    def list_specs(self):
        return self.__source_nodes.keys()

    def pkgtosrc(self, name):
        return self.__pkgstosrc[name]

def find_circle(sourcedb, A):

    G_f = pisi.graph.Digraph()

    def get_spec(name):
        if sourcedb.has_spec(name):
            return sourcedb.get_spec(name)
        else:
            raise Exception('Cannot find source package: %s' % name)

    def get_src(name):
        return get_spec(name).source

    def add_src(src):
        if not str(src.name) in G_f.vertices():
            G_f.add_vertex(str(src.name), (src.version, src.release))

    def pkgtosrc(pkg):
        return sourcedb.pkgtosrc(pkg)

    B = A

    install_list = set()

    while len(B) > 0:
        Bp = set()
        for x in B:
            sf = get_spec(x)
            src = sf.source
            add_src(src)

            # add dependencies

            def process_dep(dep):
                srcdep = pkgtosrc(dep.package)
                if not srcdep in G_f.vertices():
                    Bp.add(srcdep)
                    add_src(get_src(srcdep))
                if not src.name == srcdep: # firefox - firefox-devel thing
                    G_f.add_edge(src.name, srcdep)

            for builddep in src.buildDependencies:
                process_dep(builddep)

            for pkg in sf.packages:
                for rtdep in pkg.packageDependencies:
                    process_dep(rtdep)
        B = Bp

        try:
            order_build = G_f.topological_sort()
            order_build.reverse()
        except CycleException, cycle:
            return str(cycle)

    return ""

if __name__ == "__main__":

    if len(sys.argv) < 2:
        print "Usage: circlefinder.py <source repo pisi-index.xml file>"
        sys.exit(1)

    sourcedb = SourceDB(sys.argv[1])
    cycles = set()
    sources = sourcedb.list_specs()
    ls = len(sources)
    i = 0
    for pkg in sources:
        i += 1
        sys.stdout.write("\r(%04d/%d) Calculating build dep of %s                       " % (i, ls, pkg))
        sys.stdout.flush()
        cycles.add(find_circle(sourcedb, [pkg]))

    for cycle in cycles:
        print cycle