Add JSON input (#3)

Co-authored-by: Smaug123 <patrick+github@patrickstevens.co.uk>
Reviewed-on: #3

AnkiStatic.Lib/Domain/Deck.fs

@@ -0,0 +1,58 @@
+namespace AnkiStatic
+
+open System
+open System.Text.Json
+
+type Deck =
+    {
+        // We'll assume newToday, revToday, lrnToday, timeToday are all [0,0]
+        Name : string
+        ExtendedReviewLimit : int option
+        ExtendedNewCardLimit : int option
+        UpdateSequenceNumber : int
+        Collapsed : bool
+        BrowserCollapsed : bool
+        Description : string
+        LastModified : DateTimeOffset
+    }
+
+[<RequireQualifiedAccess>]
+module Deck =
+    let toJson (id : int64) (model : DateTimeOffset option) (this : Deck) : string =
+        let extendRev =
+            match this.ExtendedReviewLimit with
+            | None -> ""
+            | Some rev -> sprintf "\"extendRev\": %i," rev
+
+        let extendNew =
+            match this.ExtendedNewCardLimit with
+            | None -> ""
+            | Some lim -> sprintf "\"extendNew\": %i," lim
+
+        let model =
+            match model with
+            | None -> ""
+            | Some model -> model.ToUnixTimeMilliseconds () |> sprintf "\"mod\": %i,"
+
+        // TODO: what is `conf`?
+        $"""{{
+    "name": %s{JsonSerializer.Serialize this.Name},
+    "desc": %s{JsonSerializer.Serialize this.Description},
+    %s{extendRev}
+    "usn": %i{this.UpdateSequenceNumber},
+    "collapsed": %b{this.Collapsed},
+    "newToday": [0,0],
+    "timeToday": [0,0],
+    "revToday": [0,0],
+    "lrnToday": [0,0],
+    "dyn": 0,
+    %s{model}
+    %s{extendNew}
+    "conf": 1,
+    "id": %i{id},
+    "mod": %i{this.LastModified.ToUnixTimeSeconds ()}
+}}"""
+
+
+[<Measure>]
+type deck