// ParasitemIA Zipped file format.
module Parasitemia.GUI.PiaZ

open System
open System.Windows
open System.IO
open System.IO.Compression

open FSharp.Data

open Emgu.CV
open Emgu.CV.Structure

open Types

let extension = ".piaz"
let filter = "PIA|*.piaz"

type FileData = {
    sources: SourceImage list
    patientID: string }

// The json type associated to a source image.
type JSONSourceImage = JsonProvider<"""
    {
        "RBCRadius" : 32.5,
        "dateLastAnalysis" : 1.5,
        "rbcs": [
            {
                "num": 1,
                "infected": true,
                "setManually": false,
                "posX" : 42.5,
                "posY" : 42.5,
                "width" : 10.5,
                "height" : 10.5,
                "stainArea" : 10
            }
        ]
    }
""">

// The json type associated to a file.
type JSONMainInformation = JsonProvider<"""
    {
        "patientID": "1234abcd"
    }
""">

let mainFilename = "info.json"
let imageExtension = ".tiff"

let save (filePath: string) (data: FileData) =
    use file = ZipFile.Open(filePath, ZipArchiveMode.Update)

    for e in List.ofSeq file.Entries do // 'ofSeq' to not iterate a collection currently modified.
        e.Delete()

    // Main JSON file.
    let mainJSON = JSONMainInformation.Root(data.patientID)
    let mainFile = file.CreateEntry(mainFilename, CompressionLevel.Fastest)
    use mainFileWriter = new StreamWriter(mainFile.Open())
    mainJSON.JsonValue.WriteTo(mainFileWriter, JsonSaveOptions.None)

    // Write each images and the associated information.
    for imgSrc in data.sources do
        let imgFilename = (string imgSrc.num) + imageExtension
        let imgEntry = file.CreateEntry(imgFilename, CompressionLevel.NoCompression) // FIXME: It seems a compression is applied to this file despite of the 'NoCompression' flag.
        imgSrc.img.ToBitmap().Save(imgEntry.Open(), System.Drawing.Imaging.ImageFormat.Tiff)

        let imgJSON =
            JSONSourceImage.Root(decimal imgSrc.rbcRadius,
                                 decimal <| imgSrc.dateLastAnalysis.ToFileTimeUtc(),
                                 [| for rbc in imgSrc.rbcs ->
                                       JSONSourceImage.Rbc(
                                            rbc.num,
                                            rbc.infected, rbc.setManually,
                                            decimal rbc.center.X, decimal rbc.center.Y, decimal rbc.size.Width, decimal rbc.size.Height,
                                            rbc.infectedArea) |])

        let imgJSONEntry = file.CreateEntry(imgFilename + ".json", CompressionLevel.Fastest)
        use imgJSONFileWriter = new StreamWriter(imgJSONEntry.Open())
        imgJSON.JsonValue.WriteTo(imgJSONFileWriter, JsonSaveOptions.None)


let load (filePath: string) : FileData =
    use file = ZipFile.Open(filePath, ZipArchiveMode.Read)

    let mainFile = file.GetEntry(mainFilename)
    let mainJSON = JSONMainInformation.Load(mainFile.Open())

    let sources = [
        let mutable imgNum = 0
        for imgEntry in file.Entries do
            let filename = imgEntry.Name
            if filename.EndsWith(imageExtension)
            then
                let img = new Image<Bgr, byte>(new System.Drawing.Bitmap(imgEntry.Open(), false)) // FIXME: Should we dispose the bitmap?
                imgNum <- imgNum + 1
                let imgJSONEntry = file.GetEntry(filename + ".json")
                let imgJSON = JSONSourceImage.Load(imgJSONEntry.Open())
                yield { num = imgNum
                        rbcRadius = float imgJSON.RbcRadius
                        dateLastAnalysis = DateTime.FromFileTimeUtc(int64 imgJSON.DateLastAnalysis)
                        img = img
                        rbcs = [ for rbc in imgJSON.Rbcs ->
                                    { num = rbc.Num;
                                      infected = rbc.Infected; setManually = rbc.SetManually;
                                      center = Point(float rbc.PosX, float rbc.PosY); size = Size(float rbc.Width, float rbc.Height);
                                      infectedArea = rbc.StainArea } ] } ]
    { sources = sources; patientID = mainJSON.PatientId }