class Craigslister

# File lib/craigslister/main.rb, line 9
def initialize(args)
  @area    = args.fetch(:area, 'sfbay')
  @section = args.fetch(:section, 'sss')
  @item    = args[:item]
  @high    = args.fetch(:high, nil)
  @low     = args.fetch(:low, nil)
  validate_price_range
end

# File lib/craigslister/main.rb, line 18
def posts
  LinkScraper.new(url, base_url).posts
end

# File lib/craigslister/main.rb, line 22
def url
  "#{base_url}/search/#{section}?sort=rel&"\
  "#{price_query}query="\
  "#{item.downcase.split(' ') * '+'}"
end

# File lib/craigslister/main.rb, line 30
def base_url
  "https://#{area}.craigslist.org"
end

# File lib/craigslister/main.rb, line 46
def price_invalid?
  low && high && low > high
end

# File lib/craigslister/main.rb, line 34
def price_query
  result = ''
  result += "min_price=#{low}&" if low
  result += "max_price=#{high}&" if high
  result
end

# File lib/craigslister/main.rb, line 41
def validate_price_range
  fail(InvalidRangeError,
       'Price range is invalid.') if price_invalid?
end