module MyWebSite

open System
open System.IO
open Freya.Core
open Microsoft.Owin.Hosting

let helloWorld =
    freya {
        let text = "Hello World"B
        let! state = Freya.State.get
        state.Environment.["owin.ResponseStatusCode"] <- 200
        state.Environment.["owin.RepsonseReasonPhrase"] <- "Awesome"
        state.Environment.["owin.ResponseBody"] :?> Stream
            |> fun x -> x.Write (text, 0, text.Length)
        }

type Exercise() =
    member __.Configuration() =
        OwinAppFunc.ofFreya helloWorld

[<EntryPoint>]
let main _ =
    let url = "http://localhost:8080"
    WebApp.Start<Exercise> (url) |> ignore
    Console.WriteLine("Serving site at " + url)
    Console.WriteLine("Press ENTER to cancel")
    Console.ReadLine |> ignore

// Working with Freya lenses
open Freya.Lenses.Http

// Working directly with the types if required
open Arachne.Http

// The previous way, using raw access to the state
let readPathRaw =
    freya {
        let! state = Freya.getState
        return state.Environment.["owin.RequestPath"] :?> string }

// The lens way
let readPathLens =
    freya {
        return! Freya.get Request.path_ }

let readAccept =
    freya {
        return! Freya.get Request.Headers.accept_ }

// Might return something like...

Some (Accept [
    AcceptableMedia (
        Open (Parameters (Map.empty)),
        Some (AcceptParameters (Weight 0.3, Extensions (Map.empty))))
    AcceptableMedia (
        Partial (Type "text", Parameters (Map.empty)),
        Some (AcceptParameters (Weight 0.9, Extensions (Map.empty)))) ])

type Page = { Number: int; Footnote: string; Content: string }
type Book = { Title: string; Page: Page }
type Author = { Name: string; Book: Book }

// Given a Book we can trivially retrieve its page's content:
let pageContent = author.Book.Page.Content

// Setting the page nummber is a bit more problematic though. 
//If this were mutable, we could just do:
author.Book.Page.Number <- 15

// But it's not, so we use F# copy-and-update syntax:
let author2 = { author with Book = 
                { author.Book with Page = 
                    { author.Book.Page with Number = 15 } } }
                    

// Properties
let mediaTypes = [ MediaType.Text ]
let methods = [ GET ]

// Decisions
let available = Freya.init true

// Handlers
let content _ =
    Freya.init
      {  Description =
            {  Charset = Some Charset.Utf8
               Encodings = None
               MediaType = Some MediaType.Text
               Languages = None }
         Data = "Hello World!"B } }

// Resource
let helloWorld =
    freyaMachine {
        using http
        mediaTypesSupported mediaTypes
        methodsSupported methods
        serviceAvailable available
        handleOk content } 

type Exercise() =
    member __.Configuration() =
        OwinAppFunc.ofFreya helloWorld

[<EntryPoint>]
let main _ =
    let url = "http://localhost:8080"
    let _ = WebApp.Start<Exercise> (url)
    Console.WriteLine("Serving site at " + url)
    Console.WriteLine("Press ENTER to cancel")
    let _ = Console.ReadLine ()
    0