5 files changed, 276 insertions, 0 deletions
diff --git a/editor/state/dune b/editor/state/dune
new file mode 100755
index 0000000..dd405a1
--- /dev/null
+++ b/editor/state/dune
@@ -0,0 +1,9 @@
+(library
+ (name state)
+ (libraries 
+   brr
+   prosemirror
+   plugins
+   )
+ (preprocess (pps js_of_ocaml-ppx))
+ )
diff --git a/editor/state/state.ml b/editor/state/state.ml
new file mode 100755
index 0000000..48b4d58
--- /dev/null
+++ b/editor/state/state.ml
@@ -0,0 +1,70 @@
+open Brr
+module PM = Prosemirror
+module Js = Js_of_ocaml.Js
+
+module Storage = Storage
+
+(** This is the state for the application *)
+type t =
+  { editable : bool
+  ; view : PM.View.editor_view Js.t
+  ; last_backup: float
+  ; page_id: Jstr.t option
+
+  ; window : Brr.El.t list
+  ; pm : PM.t
+  }
+
+(** Compare two states together.
+
+    The prosemirror elemens are ignored
+
+*)
+let eq s1 s2 =
+  Stdlib.(==)
+    ( s1.editable
+    , s1.last_backup
+    , s1.page_id
+    , s1.window )
+
+    ( s2.editable
+    , s2.last_backup
+    , s2.page_id
+    , s2.window )
+
+let set_title
+  : Storage.content Js.t -> unit
+  = fun content ->
+    let title =
+      Js.Opt.get
+        content##.title
+        (fun () -> Jstr.empty) in
+    let title_element = Document.find_el_by_id G.document (Jstr.v "title") in
+    Option.iter
+      (fun el -> El.set_prop (El.Prop.value) title el)
+      title_element
+
+let state_of_storage
+  : PM.t -> Storage.content Js.t -> PM.Model.schema Js.t -> PM.State.editor_state Js.t
+  = fun pm content schema ->
+    Js.Opt.case
+      content##.content
+      (fun () ->
+         let obj = PM.State.creation_prop () in
+         obj##.plugins := Plugins.default pm schema;
+         obj##.schema := Js.some schema;
+         PM.State.create pm obj)
+      (fun page_content ->
+         let obj = PM.State.configuration_prop () in
+         obj##.plugins := Plugins.default pm schema;
+         obj##.schema := Js.some schema;
+         PM.State.fromJSON pm obj page_content)
+
+let load_page
+  : Jstr.t option -> t -> Storage.content Js.t -> t
+  = fun page_id state json ->
+    let editor_state = state_of_storage state.pm json state.view##.state##.schema in
+    let () = state.view##updateState editor_state
+    and () = set_title json in
+    { state with page_id }
+
diff --git a/editor/state/state.mli b/editor/state/state.mli
new file mode 100755
index 0000000..e370015
--- /dev/null
+++ b/editor/state/state.mli
@@ -0,0 +1,24 @@
+module Js = Js_of_ocaml.Js
+
+module Storage = Storage
+
+type t =
+  { editable : bool
+  ; view : Prosemirror.View.editor_view Js.t
+  ; last_backup: float
+  ; page_id: Jstr.t option
+
+  ; window : Brr.El.t list
+  ; pm : Prosemirror.t
+  }
+
+val eq: t -> t -> bool
+
+val set_title
+  : Storage.content Js.t -> unit
+
+val state_of_storage
+  : Prosemirror.t -> Storage.content Js.t -> Prosemirror.Model.schema Js.t -> Prosemirror.State.editor_state Js.t
+
+val load_page
+  : Jstr.t option -> t -> Storage.content Js.t -> t
diff --git a/editor/state/storage.ml b/editor/state/storage.ml
new file mode 100755
index 0000000..f893c2d
--- /dev/null
+++ b/editor/state/storage.ml
@@ -0,0 +1,137 @@
+open Brr
+module Js = Js_of_ocaml.Js
+
+let storage_key = (Jstr.v "editor")
+
+let storage = Brr_io.Storage.local G.window
+
+class type content = object
+
+  method title
+    : Jstr.t Js.opt Js.readonly_prop
+
+  method content
+    : Jv.t Js.opt Js.readonly_prop
+
+  method date
+    : float Js.opt Js.readonly_prop
+
+end
+
+let page_id
+  : unit -> Jstr.t option
+  = fun () ->
+    let uri = Brr.Window.location Brr.G.window in
+    let query = Brr.Uri.query uri in
+    let params = Brr.Uri.Params.of_jstr query in
+    Brr.Uri.Params.find (Jstr.v "page") params
+
+(** [load' pm schema content key] will load the content stored in the local
+    storage for the [key].
+*)
+let load'
+  : Jstr.t -> content Js.t
+  = fun key ->
+
+    let opt_data = Brr_io.Storage.get_item storage key in
+    match opt_data with
+    | None ->
+      object%js
+        val title = Js.null
+        val content = Js.null
+        val date = Js.null
+      end
+    | Some contents ->
+
+      (* Try to load from the storage *)
+      match Json.decode contents with
+      | Error _ ->
+        object%js
+          val title = Js.null
+          val content = Js.null
+          val date = Js.null
+        end
+
+      | Ok json ->
+        Jv.Id.of_jv json
+
+(** Save the view *)
+let save'
+  : check:(content Js.t -> bool) -> content Js.t -> Jstr.t -> (bool, Jv.Error.t) result
+  = fun ~check object_content key ->
+
+    (* First load the content from the storage *)
+    match check (load' key) with
+    | false -> Ok false
+    | true ->
+      let storage = Brr_io.Storage.local G.window in
+      let operation = Brr_io.Storage.set_item
+          storage
+          key
+          (Json.encode @@ Jv.Id.to_jv @@ object_content) in
+      Result.map (fun () -> true) operation
+
+
+(** [load pm schema content f] will try load the content stored in the local
+    storage. The right key is given by the result of the function [f]
+*)
+let load
+  : Jstr.t option -> content Js.t
+  = fun key ->
+    match key with
+    | None -> load' storage_key
+    | Some value ->
+      let key = Jstr.concat
+          ~sep:(Jstr.v "_")
+          [storage_key ;  value] in
+      load' key
+
+let save
+  : check:(content Js.t -> bool) -> content Js.t -> Jstr.t option -> (bool, Jv.Error.t) result
+  = fun ~check object_content key ->
+    match key with
+    | None ->
+      save' ~check object_content storage_key
+    | Some value ->
+      let key = Jstr.concat
+          ~sep:(Jstr.v "_")
+          [storage_key ;  value] in
+      save' ~check object_content key
+
+let delete
+  : (unit -> Jstr.t option) -> unit
+  = fun f ->
+    match f () with
+    | None -> ()
+    | Some value ->
+      let key = Jstr.concat
+          ~sep:(Jstr.v "_")
+          [storage_key ;  value] in
+      let storage = Brr_io.Storage.local G.window in
+      Brr_io.Storage.remove_item storage key
+
+let get_ids
+  : unit -> Jstr.t list
+  = fun () ->
+    let open Brr_io in
+    let storage = Storage.local G.window in
+    let items = Storage.length storage in
+
+    let sub = Jstr.( storage_key + (v "_") ) in
+    let start = Jstr.length sub in
+
+    let rec add_element acc = function
+      | -1 -> acc
+      | nb ->
+        begin match Storage.key storage nb with
+          | Some key when (Jstr.starts_with ~sub key) ->
+
+            let key_name = Jstr.sub key
+                ~start in
+            add_element (key_name::acc) (nb -1)
+          | _ ->
+            add_element acc (nb -1)
+        end
+
+    in
+    add_element [] items
diff --git a/editor/state/storage.mli b/editor/state/storage.mli
new file mode 100755
index 0000000..5b7e0a0
--- /dev/null
+++ b/editor/state/storage.mli
@@ -0,0 +1,36 @@
+module Js = Js_of_ocaml.Js
+
+(** Provide a function for extracting the page id from the URL *)
+val page_id
+  : unit -> Jstr.t option
+
+class type content = object
+
+  method title
+    : Jstr.t Js.opt Js.readonly_prop
+
+  method content
+    : Jv.t Js.opt Js.readonly_prop
+
+  method date 
+    : float Js.opt Js.readonly_prop
+
+end
+
+(** load f] will try to load the content associated with the given key.
+
+    The function [f] is called to identified which is the appropriate page id.
+*)
+val load
+  : Jstr.t option -> content Js.t
+
+val save
+  : check:(content Js.t -> bool) -> content Js.t -> Jstr.t option -> (bool, Jv.Error.t) result
+
+(** Remove the page from the storage. *)
+val delete 
+  : (unit -> Jstr.t option) -> unit
+
+(** Collect all the keys to the existing pages *)
+val get_ids
+  : unit -> Jstr.t list