module Rake::Funnel
  class AmbiguousFileError < StandardError
    attr_reader :task_name, :search_pattern, :candidates, :description

    def initialize(message, task_name, search_pattern, candidates)
      description = "Could not run task '#{task_name}'. #{message}"
      super(description)

      @description = description
      @task_name = task_name
      @search_pattern = search_pattern
      @candidates = candidates
    end

    def to_s
      msg = []
      (msg << description) if description
      (msg << "Search pattern used: #{@search_pattern}") if @search_pattern
      unless (@candidates || []).empty?
        msg << 'Candidates:'
        msg << @candidates.map { |c| "  - #{c}" }
      end

      msg = [super.to_s] if msg.empty?

      msg.join("\n")
    end
  end
end