class Bundler::Resolver

# File bundler/resolver.rb, line 27
def initialize(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
  @source_requirements = source_requirements
  @base = base
  @resolver = Molinillo::Resolver.new(self, self)
  @search_for = {}
  @base_dg = Molinillo::DependencyGraph.new
  @base.each do |ls|
    dep = Dependency.new(ls.name, ls.version)
    @base_dg.add_vertex(ls.name, DepProxy.get_proxy(dep, ls.platform), true)
  end
  additional_base_requirements.each {|d| @base_dg.add_vertex(d.name, d) }
  @platforms = platforms.reject {|p| p != Gem::Platform::RUBY && (platforms - [p]).any? {|pl| generic(pl) == p } }
  @resolving_only_for_ruby = platforms == [Gem::Platform::RUBY]
  @gem_version_promoter = gem_version_promoter
  @use_gvp = Bundler.feature_flag.use_gem_version_promoter_for_major_updates? || !@gem_version_promoter.major?
end

# File bundler/resolver.rb, line 218
def self.platform_sort_key(platform)
  # Prefer specific platform to not specific platform
  return ["99-LAST", "", "", ""] if Gem::Platform::RUBY == platform
  ["00", *platform.to_a.map {|part| part || "" }]
end

# File bundler/resolver.rb, line 20
def self.resolve(requirements, source_requirements = {}, base = [], gem_version_promoter = GemVersionPromoter.new, additional_base_requirements = [], platforms = nil)
  base = SpecSet.new(base) unless base.is_a?(SpecSet)
  resolver = new(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
  result = resolver.start(requirements)
  SpecSet.new(SpecSet.new(result).for(requirements.reject{|dep| dep.name.end_with?("\0") }))
end

# File bundler/resolver.rb, line 93
def after_resolution
  Bundler.ui.info ""
end

# File bundler/resolver.rb, line 89
def before_resolution
  Bundler.ui.info "Resolving dependencies...", debug?
end

# File bundler/resolver.rb, line 72
def debug(depth = 0)
  return unless debug?
  debug_info = yield
  debug_info = debug_info.inspect unless debug_info.is_a?(String)
  puts debug_info.split("\n").map {|s| depth == 0 ? "BUNDLER: #{s}" : "BUNDLER(#{depth}): #{s}" }
end

# File bundler/resolver.rb, line 79
def debug?
  return @debug_mode if defined?(@debug_mode)
  @debug_mode =
    ENV["BUNDLER_DEBUG_RESOLVER"] ||
    ENV["BUNDLER_DEBUG_RESOLVER_TREE"] ||
    ENV["DEBUG_RESOLVER"] ||
    ENV["DEBUG_RESOLVER_TREE"] ||
    false
end

# File bundler/resolver.rb, line 198
def dependencies_equal?(dependencies, other_dependencies)
  dependencies.map(&:dep) == other_dependencies.map(&:dep)
end

# File bundler/resolver.rb, line 103
def dependencies_for(specification)
  specification.dependencies_for_activated_platforms
end

# File bundler/resolver.rb, line 166
def index_for(dependency)
  source_for(dependency.name).specs
end

# File bundler/resolver.rb, line 97
def indicate_progress
  Bundler.ui.info ".", false unless debug?
end

# File bundler/resolver.rb, line 178
def name_for(dependency)
  dependency.name
end

# File bundler/resolver.rb, line 182
def name_for_explicit_dependency_source
  Bundler.default_gemfile.basename.to_s
rescue StandardError
  "Gemfile"
end

# File bundler/resolver.rb, line 188
def name_for_locking_dependency_source
  Bundler.default_lockfile.basename.to_s
rescue StandardError
  "Gemfile.lock"
end

# File bundler/resolver.rb, line 194
def requirement_satisfied_by?(requirement, activated, spec)
  requirement.matches_spec?(spec) || spec.source.is_a?(Source::Gemspec)
end

# File bundler/resolver.rb, line 174
def results_for(dependency, base)
  index_for(dependency).search(dependency, base)
end

# File bundler/resolver.rb, line 107
def search_for(dependency_proxy)
  platform = dependency_proxy.__platform
  dependency = dependency_proxy.dep
  name = dependency.name
  @search_for[dependency_proxy] ||= begin
    results = results_for(dependency, @base[name])

    if vertex = @base_dg.vertex_named(name)
      locked_requirement = vertex.payload.requirement
    end

    if !@prerelease_specified[name] && (!@use_gvp || locked_requirement.nil?)
      # Move prereleases to the beginning of the list, so they're considered
      # last during resolution.
      pre, results = results.partition {|spec| spec.version.prerelease? }
      results = pre + results
    end

    spec_groups = if results.any?
      nested = []
      results.each do |spec|
        version, specs = nested.last
        if version == spec.version
          specs << spec
        else
          nested << [spec.version, [spec]]
        end
      end
      nested.reduce([]) do |groups, (version, specs)|
        next groups if locked_requirement && !locked_requirement.satisfied_by?(version)
        next groups unless specs.any? {|spec| spec.match_platform(platform) }

        specs_by_platform = Hash.new do |current_specs, current_platform|
          current_specs[current_platform] = select_best_platform_match(specs, current_platform)
        end

        spec_group_ruby = SpecGroup.create_for(specs_by_platform, [Gem::Platform::RUBY], Gem::Platform::RUBY)
        groups << spec_group_ruby if spec_group_ruby

        next groups if @resolving_only_for_ruby

        spec_group = SpecGroup.create_for(specs_by_platform, @platforms, platform)
        groups << spec_group

        groups
      end
    else
      []
    end
    # GVP handles major itself, but it's still a bit risky to trust it with it
    # until we get it settled with new behavior. For 2.x it can take over all cases.
    if !@use_gvp
      spec_groups
    else
      @gem_version_promoter.sort_versions(dependency, spec_groups)
    end
  end
end

# File bundler/resolver.rb, line 202
def sort_dependencies(dependencies, activated, conflicts)
  dependencies.sort_by do |dependency|
    name = name_for(dependency)
    vertex = activated.vertex_named(name)
    [
      @base_dg.vertex_named(name) ? 0 : 1,
      vertex.payload ? 0 : 1,
      vertex.root? ? 0 : 1,
      amount_constrained(dependency),
      conflicts[name] ? 0 : 1,
      vertex.payload ? 0 : search_for(dependency).count,
      self.class.platform_sort_key(dependency.__platform),
    ]
  end
end

# File bundler/resolver.rb, line 170
def source_for(name)
  @source_requirements[name] || @source_requirements[:default]
end

# File bundler/resolver.rb, line 44
def start(requirements)
  @gem_version_promoter.prerelease_specified = @prerelease_specified = {}
  requirements.each {|dep| @prerelease_specified[dep.name] ||= dep.prerelease? }

  verify_gemfile_dependencies_are_found!(requirements)
  dg = @resolver.resolve(requirements, @base_dg)
  dg.
    map(&:payload).
    reject {|sg| sg.name.end_with?("\0") }.
    map(&:to_specs).
    flatten
rescue Molinillo::VersionConflict => e
  message = version_conflict_message(e)
  raise VersionConflict.new(e.conflicts.keys.uniq, message)
rescue Molinillo::CircularDependencyError => e
  names = e.dependencies.sort_by(&:name).map {|d| "gem '#{d.name}'" }
  raise CyclicDependencyError, "Your bundle requires gems that depend" \
    " on each other, creating an infinite loop. Please remove" \
    " #{names.count > 1 ? "either " : ""}#{names.join(" or ")}" \
    " and try again."
end

# File bundler/resolver.rb, line 232
def amount_constrained(dependency)
  @amount_constrained ||= {}
  @amount_constrained[dependency.name] ||= begin
    if (base = @base[dependency.name]) && !base.empty?
      dependency.requirement.satisfied_by?(base.first.version) ? 0 : 1
    else
      all = index_for(dependency).search(dependency.name).size

      if all <= 1
        all - 1_000_000
      else
        search = search_for(dependency)
        search = @prerelease_specified[dependency.name] ? search.count : search.count {|s| !s.version.prerelease? }
        search - all
      end
    end
  end
end

# File bundler/resolver.rb, line 273
def gem_not_found_message(name, requirement, source, extra_message = "")
  specs = source.specs.search(name)
  matching_part = name
  requirement_label = SharedHelpers.pretty_dependency(requirement)
  cache_message = begin
                      " or in gems cached in #{Bundler.settings.app_cache_path}" if Bundler.app_cache.exist?
                    rescue GemfileNotFound
                      nil
                    end
  specs_matching_requirement = specs.select {| spec| requirement.matches_spec?(spec) }

  if specs_matching_requirement.any?
    specs = specs_matching_requirement
    matching_part = requirement_label
    requirement_label = "#{requirement_label} #{requirement.__platform}"
  end

  message = String.new("Could not find gem '#{requirement_label}'#{extra_message} in #{source}#{cache_message}.\n")

  if specs.any?
    message << "\nThe source contains the following gems matching '#{matching_part}':\n"
    message << specs.map {|s| "  * #{s.full_name}" }.join("\n")
  end

  message
end

# File bundler/resolver.rb, line 251
def verify_gemfile_dependencies_are_found!(requirements)
  requirements.map! do |requirement|
    name = requirement.name
    next requirement if name == "bundler"
    next requirement unless search_for(requirement).empty?
    next unless requirement.current_platform?

    if (base = @base[name]) && !base.empty?
      version = base.first.version
      message = "You have requested:\n" \
        "  #{name} #{requirement.requirement}\n\n" \
        "The bundle currently has #{name} locked at #{version}.\n" \
        "Try running `bundle update #{name}`\n\n" \
        "If you are updating multiple gems in your Gemfile at once,\n" \
        "try passing them all to `bundle update`"
    else
      message = gem_not_found_message(name, requirement, source_for(name))
    end
    raise GemNotFound, message
  end.compact!
end

# File bundler/resolver.rb, line 300
def version_conflict_message(e)
  # only show essential conflicts, if possible
  conflicts = e.conflicts.dup

  if conflicts["bundler"]
    conflicts.replace("bundler" => conflicts["bundler"])
  else
    conflicts.delete_if do |_name, conflict|
      deps = conflict.requirement_trees.map(&:last).flatten(1)
      !Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
    end
  end

  e = Molinillo::VersionConflict.new(conflicts, e.specification_provider) unless conflicts.empty?

  solver_name = "Bundler"
  possibility_type = "gem"
  e.message_with_trees(
    :solver_name => solver_name,
    :possibility_type => possibility_type,
    :reduce_trees => lambda do |trees|
      # called first, because we want to reduce the amount of work required to find maximal empty sets
      trees = trees.uniq {|t| t.flatten.map {|dep| [dep.name, dep.requirement] } }

      # bail out if tree size is too big for Array#combination to make any sense
      return trees if trees.size > 15
      maximal = 1.upto(trees.size).map do |size|
        trees.map(&:last).flatten(1).combination(size).to_a
      end.flatten(1).select do |deps|
        Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
      end.min_by(&:size)

      trees.reject! {|t| !maximal.include?(t.last) } if maximal

      trees.sort_by {|t| t.reverse.map(&:name) }
    end,
    :printable_requirement => lambda {|req| SharedHelpers.pretty_dependency(req) },
    :additional_message_for_conflict => lambda do |o, name, conflict|
      if name == "bundler"
        o << %(\n  Current Bundler version:\n    bundler (#{Bundler::VERSION}))

        conflict_dependency = conflict.requirement
        conflict_requirement = conflict_dependency.requirement
        other_bundler_required = !conflict_requirement.satisfied_by?(Gem::Version.new(Bundler::VERSION))

        if other_bundler_required
          o << "\n\n"

          candidate_specs = source_for(:default_bundler).specs.search(conflict_dependency)
          if candidate_specs.any?
            target_version = candidate_specs.last.version
            new_command = [File.basename($PROGRAM_NAME), "_#{target_version}_", *ARGV].join(" ")
            o << "Your bundle requires a different version of Bundler than the one you're running.\n"
            o << "Install the necessary version with `gem install bundler:#{target_version}` and rerun bundler using `#{new_command}`\n"
          else
            o << "Your bundle requires a different version of Bundler than the one you're running, and that version could not be found.\n"
          end
        end
      elsif conflict.locked_requirement
        o << "\n"
        o << %(Running `bundle update` will rebuild your snapshot from scratch, using only\n)
        o << %(the gems in your Gemfile, which may resolve the conflict.\n)
      elsif !conflict.existing && !name.end_with?("\0")
        o << "\n"

        relevant_source = conflict.requirement.source || source_for(name)

        extra_message = if conflict.requirement_trees.first.size > 1
          ", which is required by gem '#{SharedHelpers.pretty_dependency(conflict.requirement_trees.first[-2])}',"
        else
          ""
        end

        o << gem_not_found_message(name, conflict.requirement, relevant_source, extra_message)
      end
    end,
    :version_for_spec => lambda {|spec| spec.version },
    :incompatible_version_message_for_conflict => lambda do |name, _conflict|
      if name.end_with?("\0")
        %(#{solver_name} found conflicting requirements for the #{name} version:)
      else
        %(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
      end
    end
  )
end