module EhcFetch

# File lib/ehc_fetch.rb, line 29
def default_fetch
  ->(url) { http_get(url) }
end

# File lib/ehc_fetch.rb, line 89
def extract_cookie_names(set_cookie)
  Array(set_cookie).flat_map do |entry|
    entry.to_s.split(";").first.to_s.split("=", 2).first.to_s.strip
  end.reject(&:empty?).uniq
end

# File lib/ehc_fetch.rb, line 71
def extract_security_headers(headers)
  data = headers.is_a?(Hash) ? headers : {}
  lines = []

  SECURITY_HEADER_KEYS.each do |key|
    value = data[key]
    next if value.to_s.strip.empty?

    label = key.tr("-", " ").split.map(&:capitalize).join(" ")
    lines << "#{label}: #{value}"
  end

  cookies = extract_cookie_names(data["set-cookie"])
  lines << "Cookies: #{cookies.join(', ')}" if cookies.any?

  lines
end

# File lib/ehc_fetch.rb, line 25
def fetch(url, fetch: nil)
  (fetch || default_fetch).call(url)
end

# File lib/ehc_fetch.rb, line 95
def format_status_line(status:, content_type: nil)
  parts = ["HTTP #{status}"]
  type = content_type.to_s.split(";").first.to_s.strip
  parts << type unless type.empty?
  parts.join(" \u00b7 ")
end

# File lib/ehc_fetch.rb, line 40
def http_get(url, user_agent: USER_AGENT)
  uri = URI.parse(url.to_s)
  raise URI::InvalidURIError, "missing host" if uri.host.to_s.strip.empty?

  http = Net::HTTP.new(uri.host, uri.port)
  http.use_ssl = (uri.scheme == "https")
  http.open_timeout = 10
  http.read_timeout = 15

  request = Net::HTTP::Get.new(uri)
  request["User-Agent"] = user_agent

  response = http.request(request)
  {
    status: response.code.to_i,
    headers: normalize_headers(response),
    body: response.body.to_s
  }
rescue StandardError => e
  { error: e.message.to_s }
end

# File lib/ehc_fetch.rb, line 62
def normalize_headers(response)
  headers = {}
  response.each_header do |key, value|
    headers[key.downcase] = value
  end
  headers["set-cookie"] = response.get_fields("set-cookie") if response.get_fields("set-cookie")
  headers
end

# File lib/ehc_fetch.rb, line 33
def robots_url(page_url)
  uri = URI.parse(page_url.to_s)
  "#{uri.scheme}://#{uri.host}/robots.txt"
rescue URI::InvalidURIError
  nil
end