module Parasitemia.GUI.State

open System
open System.Collections.Generic
open System.Windows

open Emgu.CV
open Emgu.CV.Structure

open Types

type State () =
    let sourceImages = List<SourceImage>()
    let mutable alteredSinceLastSave = false
    let mutable patientID = ""

    member this.AlteredSinceLastSave = alteredSinceLastSave
    member val CurrentImage: SourceImage option = None with get, set
    member val FilePath: string = "" with get, set

    member this.PatientID
        with get () : string = patientID
        and set id =
            if id <> patientID
            then
                alteredSinceLastSave <- true
                patientID <- id

    member this.ImageParasitemia (srcImg: SourceImage) : int * int =
        List.length srcImg.rbcs,
        srcImg.rbcs |> List.fold (fun nbInfected rbc -> if rbc.infected then nbInfected + 1 else nbInfected) 0

    member this.GlobalParasitemia : int * int =
        sourceImages
        |> Seq.fold (fun (nbTotal, nbTotalInfected) srcImg ->
                        let nb, nbInfected = this.ImageParasitemia srcImg
                        nbTotal + nb, nbTotalInfected + nbInfected) (0, 0)


    member this.SetAsInfected (rbc: RBC) (infected: bool) =
        if infected <> rbc.infected
        then
            alteredSinceLastSave <- true
            rbc.infected <- infected
            rbc.setManually <- not rbc.setManually

    member this.Save () =
        let data = { PiaZ.FileData.patientID = this.PatientID; PiaZ.FileData.images = List.ofSeq sourceImages }
        PiaZ.save this.FilePath data
        alteredSinceLastSave <- false

    member this.Load () =
        let data = PiaZ.load this.FilePath
        this.PatientID <- data.patientID
        sourceImages.Clear()
        sourceImages.InsertRange(0, data.images)
        if sourceImages.Count > 0
        then this.CurrentImage <- Some sourceImages.[0]
        alteredSinceLastSave <- false

    member this.AddSourceImage (filePath: string) (defaultConfig: Config.Config) : SourceImage =
        let srcImg = { num = sourceImages.Count + 1; config = defaultConfig.Copy(); dateLastAnalysis = DateTime(0L); rbcs = []; img = new Image<Bgr, byte>(filePath) }
        sourceImages.Add(srcImg)
        if sourceImages.Count = 1
        then this.CurrentImage <- Some sourceImages.[0]
        alteredSinceLastSave <- true
        srcImg

    member this.RemoveSourceImage (srcImg: SourceImage) =
        let isCurrent =
            match this.CurrentImage with
            | Some srcImg' -> srcImg = srcImg'
            | _ -> false

        if sourceImages.Remove(srcImg)
        then
            alteredSinceLastSave <- true
            if isCurrent
            then
                this.CurrentImage <- if sourceImages.Count > 0 then Some sourceImages.[0] else None
        // Re-numbered the images.
        sourceImages |> Seq.iteri (fun i srcImg -> srcImg.num <- i + 1)

    member this.SetResult (imgNum: int) (cells: Cell list) =
        let sourceImage = sourceImages.Find(fun srcImg -> srcImg.num = imgNum)

        let w = sourceImage.img.Width
        let h = sourceImage.img.Height

        sourceImage.dateLastAnalysis <- DateTime.UtcNow

        // To match with previously manually altered RBC.
        let manuallyAlteredPreviousRBCS = sourceImage.rbcs |> List.filter (fun rbc -> rbc.setManually)
        let tolerance = (float sourceImage.config.RBCRadius.Pixel) * 0.5 // +/-.
        let getPreviousRBC (center: Point) : RBC option =
            manuallyAlteredPreviousRBCS |> List.tryFind (fun rbc -> rbc.center.X > center.X - tolerance && rbc.center.X < center.X + tolerance &&
                                                                    rbc.center.Y > center.Y - tolerance && rbc.center.Y < center.Y + tolerance)

        sourceImage.rbcs <- cells
            |> List.filter (fun cell -> match cell.cellClass with HealthyRBC | InfectedRBC -> true | _ -> false )
            |> List.sortByDescending (fun cell -> cell.infectedArea, (w - cell.center.X) + (h - cell.center.Y))
            |> List.mapi (fun i cell ->
                let center = Point(float cell.center.X, float cell.center.Y)
                let infected, setManually =
                    match getPreviousRBC center with
                    | Some rbc -> rbc.infected, true
                    | _ -> cell.cellClass = InfectedRBC, false

                { num = i + 1
                  infected = infected
                  setManually = setManually
                  center = center
                  size = Size(float cell.elements.Width, float cell.elements.Height)
                  infectedArea = cell.infectedArea })

        alteredSinceLastSave <- true

    member this.SourceImages : SourceImage seq =
        sourceImages :> SourceImage seq

    member this.Reset () =
        this.PatientID <- ""
        this.FilePath <- ""
        this.CurrentImage <- None
        sourceImages.Clear()
        alteredSinceLastSave <- false