require "base64"
require "json"
require "yaml"

module FaaStRuby
  macro require_handler
    require {{env("HANDLER_PATH")}}
  end
  class Event
    JSON.mapping(
      body: String?,
      headers: Hash(String, String | Nil),
      context: String?,
      query_params: Hash(String, String | Nil)
    )
  end

  class Response
    @@rendered = false
    property "body"
    property "status"
    property "headers"
    property "io"
    property "binary"
    def initialize(@body : String?, @status : Int32, @headers : Hash(String, String), @binary : Bool = false)
      @io = nil
    end

    def initialize(@io : Bytes, @status : Int32, @headers : Hash(String, String), @binary : Bool = true)
    end

    def payload
      if io
        hash = {
          "response" => Base64.encode(io.not_nil!),
          "status" => status,
          "headers" => headers,
          "binary" => binary
        }
      else
        hash = {
          "response" => body,
          "status" => status,
          "headers" => headers,
          "binary" => binary
        }
      end
      hash
    end
  end
  class Payload
    JSON.mapping(
      args: Array(JSON::Any)?,
      event: Event
    )
  end
  module Function
    def self.run(@@event : Event)
      begin
        output = handler(event)
      rescue e
        backtrace = e.backtrace.reverse.join("\n")
        puts backtrace
        puts "#{e.class.name}: #{e.message}"
        output = render json: {"error" => e.message, "location" => backtrace}.to_json, status: 500
      end
    end
  end
end

FaaStRuby.require_handler

def render(icon : String? = nil, jpeg : String? = nil, gif : String? = nil, png : String? = nil, io : Bytes? = nil, css : String? = nil, svg : String? = nil, js : String? = nil, inline : String? = nil, html : String? = nil, json : String? = nil, yaml : String? = nil, text : String? = nil, status : Int32 = 200, headers : Hash(String, String) = {} of String => String, content_type : String? = nil, binary : Bool = false)
  headers["Content-Type"] = content_type if content_type
  bin = false
  case
  when json
    headers["Content-Type"] ||= "application/json"
    resp_body = json
  when html, inline
    headers["Content-Type"] ||= "text/html"
    resp_body = html
  when text
    headers["Content-Type"] ||= "text/plain"
    resp_body = text
  when yaml
    headers["Content-Type"] ||= "text/yaml"
    resp_body = yaml
  when js
    headers["Content-Type"] ||= "text/javascript"
    resp_body = js
  when io
    headers["Content-Type"] ||= "application/octet-stream"
    bin = binary
    return FaaStRuby::Response.new(io: io, status: status, headers: headers, binary: bin)
  when png
    headers["Content-Type"] ||= "image/png"
    file = File.open(png, "rb"){|f| f.gets_to_end}
    resp_body = Base64.urlsafe_encode(file, false)
    bin = true
  when svg
    headers["Content-Type"] ||= "image/svg+xml"
    resp_body = svg
  when jpeg
    headers["Content-Type"] ||= "image/jpeg"
    file = File.open(jpeg, "rb"){|f| f.gets_to_end}
    resp_body = Base64.urlsafe_encode(file, false)
    bin = true
  when gif
    headers["Content-Type"] ||= "image/gif"
    file = File.open(gif, "rb"){|f| f.gets_to_end}
    resp_body = Base64.urlsafe_encode(file, false)
    bin = true
  when icon
    headers["Content-Type"] ||= "image/x-icon"
    file = File.read(icon)
    resp_body = Base64.urlsafe_encode(file, false)
    bin = true
  when css
    headers["Content-Type"] ||= "text/css"
    resp_body = css
  end
  FaaStRuby::Response.new(body: resp_body, status: status, headers: headers, binary: bin)
end

def redirect_to(function : String, status : Int32 = 303)
  headers = {"Location" => function}
  FaaStRuby::Response.new(body: nil, status: status, headers: headers)
end

def redirect_to(url : String, status : Int32 = 303)
  headers = {"Location" => url}
  FaaStRuby::Response.new(body: nil, status: status, headers: headers)
end

def respond_with(body : String? = nil, status : Int32 = 200, headers : Hash(String, String) = {} of String => String, binary : Bool = false)
  FaaStRuby::Response.new(body: body, status: status, headers: headers)
end

def respond_with(io : Bytes, status : Int32 = 200, headers : Hash(String, String) = {} of String => String, binary : Bool = false)
  FaaStRuby::Response.new(io: io, status: status, headers: headers, binary: binary)
end

def error(msg : String, status : Int32)
  hash = {
    "response" => msg,
    "status" => status,
    "headers" => {"Content-Type" => "application/json"}
  }
  puts "R,#{Base64.urlsafe_encode(hash.to_json, false)}"
  exit 1
end
encoded_input = STDIN.gets.not_nil!.chomp
begin
  decoded_input = Base64.decode_string(encoded_input)
  payload = FaaStRuby::Payload.from_json(decoded_input)
rescue e
  puts e.message
  error(msg: "Runtime Error. What are you trying to do?", status: 500)
  exit 1
end
spawn do
  response = FaaStRuby::Function.run(event: payload.event)
  puts "R,#{Base64.urlsafe_encode(response.payload.to_json)}"
  exit 0
end
max_time = ENV["MAX_EXECUTION_TIME"]? ? ENV["MAX_EXECUTION_TIME"].not_nil!.to_f : 60.0
sleep max_time
error(msg: "Execution expired", status: 504)
exit 1