# Copyright (c) 2013-2016 SUSE LLC
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of version 3 of the GNU General Public License as
# published by the Free Software Foundation.
#
# 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, contact SUSE LLC.
#
# To contact SUSE about this file by physical or electronic mail,
# you may find current contact information at www.suse.com

module Machinery
  class RepositoriesInspector < Machinery::Inspector
    has_priority 40
    def initialize(system, description)
      @system = system
      @description = description
    end

    def inspect(_filter, _options = {})
      if system.has_command?("zypper")
        @description.repositories = inspect_zypp_repositories
      elsif system.has_command?("yum")
        @description.repositories = inspect_yum_repositories
      elsif system.has_command?("dpkg")
        @description.repositories = inspect_apt_repositories
      else
        raise Machinery::Errors::MissingRequirement.new(
          "Need either the binary 'zypper', 'yum' or 'apt' to be available on the inspected system."
        )
      end
    end

    def summary
      "Found " \
        "#{Machinery.pluralize(
          @description.repositories.size,
          "%d repository",
          "%d repositories"
        )}."
    end

    private

    def inspect_zypp_repositories
      begin
        xml = system.run_command(
          "zypper", "--non-interactive", "--xmlout", "repos", "--details",
          stdout: :capture
        )
        details = system.run_command(
          "zypper", "--non-interactive", "repos", "--details", stdout: :capture
        ).split("\n").select { |l| l =~ /\A# +\| |\A *\d+ \| / }.
                  map { |l| l.split("|").map(&:strip) }
      rescue Cheetah::ExecutionFailed => e
        if e.status.exitstatus == 6 # ZYPPER_EXIT_NO_REPOS
          details = []
        else
          raise e
        end
      end

      if details.empty?
        result = []
      else
        priorities = parse_priorities_from_details(details)
        credentials = get_credentials_from_system
        result = parse_repositories_from_xml(xml, priorities, credentials)
      end

      RepositoriesScope.new(result, repository_system: "zypp")
    end

    def inspect_yum_repositories
      script = File.read(File.join(Machinery::ROOT, "inspect_helpers", "yum_repositories.py"))
      begin
        repositories = JSON.parse(system.run_command(
          "bash", "-c", "python", stdin: script, stdout: :capture
        ).split("\n").last).map { |element| YumRepository.new(element) }
      rescue JSON::ParserError
        raise Machinery::Errors::InspectionFailed.new("Extraction of YUM repositories failed.")
      rescue Cheetah::ExecutionFailed => e
        raise Machinery::Errors::InspectionFailed.new(
          "Extraction of YUM repositories failed:\n#{e.stderr}"
        )
      end

      RepositoriesScope.new(repositories, repository_system: "yum")
    end

    def inspect_apt_repositories
      content = system.read_file("/etc/apt/sources.list")
      begin
        content += "\n" + system.run_command(
          "bash", "-c", "cat /etc/apt/sources.list.d/*.list", stdout: :capture
        )
      rescue Cheetah::ExecutionFailed
      end

      RepositoriesScope.new(
        parse_apt_repositories(content), repository_system: "apt"
      )
    end

    def parse_apt_repositories(content)
      repositories = []
      content.each_line do |line|
        if line =~ /^\s*(deb|deb-src)\s+(cdrom:\[.+\]\/|\S+)\s+(\S+)(\s+\S[^#]*\S)?(\s*|\s*#.*)$/
          repositories << AptRepository.new(
            type: $1,
            url: $2,
            distribution: $3,
            components: $4 ? $4.strip.split(" ") : []
          )
        elsif line =~ /Types: deb/
          Machinery::Ui.warn(
            "Warning: An unsupported rfc822 style repository was found, which will be ignored."
          )
        end
      end
      repositories.uniq
    end

    def parse_priorities_from_details(details)
      # parse and remove header
      idx_prio = details.first.index("Priority")
      idx_alias = details.first.index("Alias")
      details.shift

      prio = {}
      details.each do |entry|
        prio[entry[idx_alias]] = entry[idx_prio].to_i
      end

      prio
    end

    def get_credentials_from_system
      credentials = {}
      credential_dir = "/etc/zypp/credentials.d/"
      credential_files = @system.run_command(
        "bash", "-c",
        "test -d '#{credential_dir}' && ls -1 '#{credential_dir}' || echo ''",
        stdout: :capture
      )
      credential_files.split("\n").each do |f|
        content = @system.run_command(
          "cat", "/etc/zypp/credentials.d/#{f}", stdout: :capture, privileged: true
        )
        matches = content.match(/username=(\w*)\npassword=(\w*)/)
        credentials[f] = {
          username: matches[1],
          password: matches[2]
        }
      end
      credentials
    end

    def parse_repositories_from_xml(xml, priorities, credentials)
      reps = REXML::Document.new(xml).get_elements("/stream/repo-list/repo")
      result = reps.map do |rep|
        pri_value = if rep.attributes["priority"]
          rep.attributes["priority"].to_i
        else
          priorities[rep.attributes["alias"]]
        end

        # NCC
        rep.elements["url"].first.to_s.match(/\?credentials=(\w*)/)
        cred_value = $1
        if cred_value && credentials[cred_value]
          username = credentials[cred_value][:username]
          password = credentials[cred_value][:password]
        end

        # SCC
        rep.elements["url"].first.to_s.match(/(https:\/\/updates.suse.com\/SUSE\/)/)
        scc_url = $1
        cred_value = "SCCcredentials"
        if scc_url && credentials[cred_value]
          username = credentials[cred_value][:username]
          password = credentials[cred_value][:password]
        end

        repository = ZyppRepository.new(
          alias:       rep.attributes["alias"],
          name:        rep.attributes["name"],
          type:        rep.attributes["type"],
          url:         rep.elements["url"].first.to_s,
          enabled:     rep.attributes["enabled"] == "1",
          autorefresh: rep.attributes["autorefresh"] == "1",
          gpgcheck:    rep.attributes["gpgcheck"] == "1",
          priority:    pri_value
        )
        if username && password
          repository[:username] = username
          repository[:password] = password
        end
        repository
      end.sort_by(&:name)
      result
    end
  end
end