# -*- encoding: utf-8 -*-
#
# Author:: Fletcher Nichol (<fnichol@nichol.ca>)
#
# Copyright (C) 2013, Fletcher Nichol
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

require_relative "../spec_helper"

require "kitchen/lazy_hash"

describe Kitchen::LazyHash do

  let(:context) do
    stub(:color => "blue", :metal => "heavy")
  end

  let(:hash_obj) do
    {
      :shed_color => ->(c) { c.color },
      :barn => "locked",
      :genre => proc { |c| "#{c.metal} metal" }
    }
  end

  describe "#[]" do

    it "returns regular values for keys" do
      Kitchen::LazyHash.new(hash_obj, context)[:barn].must_equal "locked"
    end

    it "invokes call on values that are lambdas" do
      Kitchen::LazyHash.new(hash_obj, context)[:shed_color].must_equal "blue"
    end

    it "invokes call on values that are Procs" do
      Kitchen::LazyHash.new(hash_obj, context)[:genre].must_equal "heavy metal"
    end
  end

  describe "#fetch" do

    it "returns regular hash values for keys" do
      Kitchen::LazyHash.new(hash_obj, context).fetch(:barn).must_equal "locked"
    end

    it "invokes call on values that are lambdas" do
      Kitchen::LazyHash.new(hash_obj, context).
        fetch(:shed_color).must_equal "blue"
    end

    it "invokes call on values that are Procs" do
      Kitchen::LazyHash.new(hash_obj, context).
        fetch(:genre).must_equal "heavy metal"
    end

    it "uses a default value for unset values" do
      Kitchen::LazyHash.new(hash_obj, context).
        fetch(:nope, "candy").must_equal "candy"
    end

    it "uses a block for unset values" do
      Kitchen::LazyHash.new(hash_obj, context).
        fetch(:nope) { |key| "#{key} is costly" }.must_equal "nope is costly"
    end
  end

  describe "#to_hash" do

    it "invokes any callable values and returns a Hash object" do
      converted = Kitchen::LazyHash.new(hash_obj, context).to_hash

      converted.must_be_instance_of Hash
      converted.fetch(:shed_color).must_equal "blue"
      converted.fetch(:barn).must_equal "locked"
      converted.fetch(:genre).must_equal "heavy metal"
    end
  end

  describe "select" do
    it "calls Procs when appropriate" do
      Kitchen::LazyHash.new(hash_obj, context).select { |_, _| true }.
        must_equal :shed_color => "blue", :barn => "locked", :genre => "heavy metal"
    end
  end

  describe "enumerable" do
    it "is an Enumerable" do
      assert Kitchen::LazyHash.new(hash_obj, context).is_a? Enumerable
    end

    it "returns an Enumerator from each() if no block given" do
      e = Kitchen::LazyHash.new(hash_obj, context).each
      e.is_a? Enumerator
      e.next.must_equal [:shed_color, "blue"]
      e.next.must_equal [:barn, "locked"]
      e.next.must_equal [:genre, "heavy metal"]
    end

    it "yields each item to the block if a block is given to each()" do
      items = []
      Kitchen::LazyHash.new(hash_obj, context).each { |i| items << i }
      items.must_equal [[:shed_color, "blue"], [:barn, "locked"], [:genre, "heavy metal"]]
    end
  end
end