# frozen_string_literal: true

module RailsMiniProfiler
  class Middleware
    def initialize(app)
      @app = app
      @config = RailsMiniProfiler.configuration
      Tracers.setup! { |trace| track_trace(trace) }
    end

    def call(env)
      request = RequestWrapper.new(env: env)
      request_context = RequestContext.new(request)
      return @app.call(env) unless Guard.new(request_context).profile?

      request_context.profiled_request = ProfiledRequest.new
      result = with_tracing(request_context) { profile(request_context) }
      return result unless request_context.authorized?

      request_context.response = ResponseWrapper.new(*result)
      complete!(request_context)
      request_context.saved? ? render_response(request_context) : result
    end

    def traces
      Thread.current[:rails_mini_profiler_traces]
    end

    def traces=(traces)
      Thread.current[:rails_mini_profiler_traces] = traces
    end

    def track_trace(event)
      return if traces.nil?

      trace = Tracers.build_trace(event)
      traces.append(trace)
    end

    private

    def complete!(request_context)
      request_context.complete_profiling!
      request_context.save_results!
      true
    rescue ActiveRecord::ActiveRecordError => e
      RailsMiniProfiler.logger.error("Could not save profile: #{e}")
      false
    end

    def render_response(request_context)
      redirect = Redirect.new(request_context).render
      return redirect if redirect

      modified_response = Badge.new(request_context).render
      [modified_response.status, modified_response.headers, modified_response.response]
    end

    def profile(request_context)
      ActiveSupport::Notifications.instrument('rails_mini_profiler.total_time') do
        request = request_context.request
        FlamegraphGuard.new(request_context).record { @app.call(request.env) }
      end
    end

    def with_tracing(request_context)
      self.traces = []
      result = yield
      request_context.traces = traces
      self.traces = nil
      result
    end
  end
end