wet-pancake/WetPancake/DataServices.fs

module internal DataServices

    open SystemServices
    open DataStructuring
    open DataProcessing
    open DataCleaning
    open System.Threading
    open System

    let rec GenerateMarkovChain (map: Map<string, string List>) (state:string) chain =
        if map.ContainsKey state then
            let nextChoice = map.[state] |> PickRandomItem
            if MatchText @"\." nextChoice then nextChoice :: chain
            else
                let currentWords =
                    state
                    |> SplitText @"\s+"
                    |> Seq.skip 1
                    |> ConcatToString
                GenerateMarkovChain map (CombineWords currentWords nextChoice) (nextChoice :: chain)
        else
            let fallbackChoice = (PickRandomItem map).Key
            String.Format("{0}.", fallbackChoice) :: chain

    let GenerateMarkovSentence map start =
        GenerateMarkovChain map start [start]
        |> List.rev
        |> ConcatToString

    (* Thread.Sleep is needed for a new random number to generate.
    Without it, the same sentence tends to repeat itself.
    When debugging (I.E. the observer effect),
    enough time passes for a new random number to generate --
    meaning a new seed or "start word" for each sentence.
    This isn't ideal but needed so please be careful when attempting to remove this line. *) 
    let GenerateMarkovText noOfSentences map =
        let startWords = fst(SeperateStartWords map)
        let result =
            seq {
                for i in 1 .. noOfSentences do
                    Thread.Sleep(100)
                    yield GenerateMarkovSentence map (PickRandomItem startWords).Key
            }
        result |> ConcatToString