module Sinatra::Templates

def asciidoc(template, options = {}, locals = {})
  render :asciidoc, template, options, locals
end

def builder(template = nil, options = {}, locals = {}, &block)
  options[:default_content_type] = :xml
  render_ruby(:builder, template, options, locals, &block)
end

def coffee(template, options = {}, locals = {})
  options.merge! :layout => false, :default_content_type => :js
  render :coffee, template, options, locals
end

def compile_block_template(template, options, &body)
  caller = settings.caller_locations.first
  path = options[:path] || caller[0]
  line = options[:line] || caller[1]
  template.new(path, line.to_i, options, &body)
end

def compile_template(engine, data, options, views)
  eat_errors = options.delete :eat_errors
  template = Tilt[engine]
  raise "Template engine not found: #{engine}" if template.nil?
  case data
  when Symbol
    template_cache.fetch engine, data, options, views do
      body, path, line = settings.templates[data]
      if body
        body = body.call if body.respond_to?(:call)
        template.new(path, line.to_i, options) { body }
      else
        found = false
        @preferred_extension = engine.to_s
        find_template(views, data, template) do |file|
          path ||= file # keep the initial path rather than the last one
          if found = File.exist?(file)
            path = file
            break
          end
        end
        throw :layout_missing if eat_errors and not found
        template.new(path, 1, options)
      end
    end
  when Proc
    compile_block_template(template, options, &data)
  when String
    template_cache.fetch engine, data, options, views do
      compile_block_template(template, options) { data }
    end
  else
    raise ArgumentError, "Sorry, don't know how to render #{data.inspect}."
  end
end

def creole(template, options = {}, locals = {})
  render :creole, template, options, locals
end

def erb(template, options = {}, locals = {}, &block)
  render(:erb, template, options, locals, &block)
end

def erubis(template, options = {}, locals = {})
  warn "Sinatra::Templates#erubis is deprecated and will be removed, use #erb instead.\n" \
    "If you have Erubis installed, it will be used automatically."
  render :erubis, template, options, locals
end

def find_template(views, name, engine)
  yield ::File.join(views, "#{name}.#{@preferred_extension}")
  Tilt.default_mapping.extensions_for(engine).each do |ext|
    yield ::File.join(views, "#{name}.#{ext}") unless ext == @preferred_extension
  end
end

def haml(template, options = {}, locals = {}, &block)
  render(:haml, template, options, locals, &block)
end

def initialize
  super
  @default_layout = :layout
  @preferred_extension = nil
end

def less(template, options = {}, locals = {})
  options.merge! :layout => false, :default_content_type => :css
  render :less, template, options, locals
end

def liquid(template, options = {}, locals = {}, &block)
  render(:liquid, template, options, locals, &block)
end

def markaby(template = nil, options = {}, locals = {}, &block)
  render_ruby(:mab, template, options, locals, &block)
end

def markdown(template, options = {}, locals = {})
  options[:exclude_outvar] = true
  render :markdown, template, options, locals
end

def mediawiki(template, options = {}, locals = {})
  render :mediawiki, template, options, locals
end

def nokogiri(template = nil, options = {}, locals = {}, &block)
  options[:default_content_type] = :xml
  render_ruby(:nokogiri, template, options, locals, &block)
end

def rabl(template, options = {}, locals = {})
  Rabl.register!
  render :rabl, template, options, locals
end

def radius(template, options = {}, locals = {})
  render :radius, template, options, locals
end

def rdoc(template, options = {}, locals = {})
  render :rdoc, template, options, locals
end

def render(engine, data, options = {}, locals = {}, &block)
  # merge app-level options
  engine_options = settings.respond_to?(engine) ? settings.send(engine) : {}
  options.merge!(engine_options) { |key, v1, v2| v1 }
  # extract generic options
  locals          = options.delete(:locals) || locals         || {}
  views           = options.delete(:views)  || settings.views || "./views"
  layout          = options[:layout]
  layout          = false if layout.nil? && options.include?(:layout)
  eat_errors      = layout.nil?
  layout          = engine_options[:layout] if layout.nil? or (layout == true && engine_options[:layout] != false)
  layout          = @default_layout         if layout.nil? or layout == true
  layout_options  = options.delete(:layout_options) || {}
  content_type    = options.delete(:default_content_type)
  content_type    = options.delete(:content_type)   || content_type
  layout_engine   = options.delete(:layout_engine)  || engine
  scope           = options.delete(:scope)          || self
  exclude_outvar  = options.delete(:exclude_outvar)
  options.delete(:layout)
  # set some defaults
  options[:outvar] ||= '@_out_buf' unless exclude_outvar
  options[:default_encoding] ||= settings.default_encoding
  # compile and render template
  begin
    layout_was      = @default_layout
    @default_layout = false
    template        = compile_template(engine, data, options, views)
    output          = template.render(scope, locals, &block)
  ensure
    @default_layout = layout_was
  end
  # render layout
  if layout
    options = options.merge(:views => views, :layout => false, :eat_errors => eat_errors, :scope => scope).
            merge!(layout_options)
    catch(:layout_missing) { return render(layout_engine, layout, options, locals) { output } }
  end
  output.extend(ContentTyped).content_type = content_type if content_type
  output
end

def render_ruby(engine, template, options = {}, locals = {}, &block)
  options, template = template, nil if template.is_a?(Hash)
  template = Proc.new { block } if template.nil?
  render engine, template, options, locals
end

def sass(template, options = {}, locals = {})
  options.merge! :layout => false, :default_content_type => :css
  render :sass, template, options, locals
end

def scss(template, options = {}, locals = {})
  options.merge! :layout => false, :default_content_type => :css
  render :scss, template, options, locals
end

def slim(template, options = {}, locals = {}, &block)
  render(:slim, template, options, locals, &block)
end

def stylus(template, options = {}, locals = {})
  options.merge! :layout => false, :default_content_type => :css
  render :styl, template, options, locals
end

def textile(template, options = {}, locals = {})
  render :textile, template, options, locals
end

def wlang(template, options = {}, locals = {}, &block)
  render(:wlang, template, options, locals, &block)
end

def yajl(template, options = {}, locals = {})
  options[:default_content_type] = :json
  render :yajl, template, options, locals
end