From 3a70d88fe606355e0121a74fa03932f364288b66 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gr=C3=A9goire=20Henry?= <gregoire.henry@ocamlpro.com>
Date: Mon, 23 Jan 2017 11:09:48 +0100
Subject: [PATCH] Shell: animated generation of `P2p.Identity`

---
 src/node/net/p2p_types.ml  | 47 ++++++++++++++++++++++++++++++++++++--
 src/node/net/p2p_types.mli |  6 +++++
 src/utils/crypto_box.ml    | 17 ++++++++++----
 src/utils/crypto_box.mli   |  2 +-
 4 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/src/node/net/p2p_types.ml b/src/node/net/p2p_types.ml
index 5ed7ded49..f8b8690fa 100644
--- a/src/node/net/p2p_types.ml
+++ b/src/node/net/p2p_types.ml
@@ -193,12 +193,55 @@ module Identity = struct
          (req "secret_key" Crypto_box.secret_key_encoding)
          (req "proof_of_work_stamp" Crypto_box.nonce_encoding))
 
-  let generate target =
+  let generate ?max target =
     let secret_key, public_key, gid = Crypto_box.random_keypair () in
     let proof_of_work_stamp =
-      Crypto_box.generate_proof_of_work public_key target in
+      Crypto_box.generate_proof_of_work ?max public_key target in
     { gid ; public_key ; secret_key ; proof_of_work_stamp }
 
+  let animation = [|
+    "|.....|" ;
+    "|o....|" ;
+    "|oo...|" ;
+    "|ooo..|" ;
+    "|.ooo.|" ;
+    "|..ooo|" ;
+    "|...oo|" ;
+    "|....o|" ;
+    "|.....|" ;
+    "|.....|" ;
+    "|.....|" ;
+    "|.....|" ;
+  |]
+
+  let init = String.make (String.length animation.(0)) '\ '
+  let clean = String.make (String.length animation.(0)) '\b'
+  let animation = Array.map (fun x -> clean ^ x) animation
+  let animation_size = Array.length animation
+  let duration = 1200 / animation_size
+
+  let generate_with_animation ppf target =
+    Format.fprintf ppf "%s%!" init ;
+    let count = ref 10000 in
+    let rec loop n =
+      let start = Mtime.counter () in
+      Format.fprintf ppf "%s%!" animation.(n mod animation_size);
+      try generate ~max:!count target
+      with Not_found ->
+        let time = Mtime.to_ms (Mtime.count start) in
+        count :=
+          if time <= 0. then
+            !count * 10
+          else
+            !count * duration / int_of_float time ;
+        loop (n+1)
+    in
+    let id = loop 0 in
+    Format.fprintf ppf "%s%s\n%!" clean init ;
+    id
+
+  let generate target = generate target
+
 end
 
 module Connection_info = struct
diff --git a/src/node/net/p2p_types.mli b/src/node/net/p2p_types.mli
index f85ed323a..a09283a69 100644
--- a/src/node/net/p2p_types.mli
+++ b/src/node/net/p2p_types.mli
@@ -94,6 +94,12 @@ module Identity : sig
   val generate : Crypto_box.target -> t
   (** [generate target] is a freshly minted identity whose proof of
       work stamp difficulty is at least equal to [target]. *)
+
+  val generate_with_animation :
+    Format.formatter -> Crypto_box.target -> t
+  (** [generate_with_animation ppf target] is a freshly minted identity
+      whose proof of work stamp difficulty is at least equal to [target]. *)
+
 end
 
 
diff --git a/src/utils/crypto_box.ml b/src/utils/crypto_box.ml
index e8d58a80d..8e9cefe63 100644
--- a/src/utils/crypto_box.ml
+++ b/src/utils/crypto_box.ml
@@ -71,11 +71,18 @@ let check_proof_of_work pk nonce target =
     ] in
   compare_target hash target
 
-let generate_proof_of_work pk target =
-  let rec loop nonce =
-    if check_proof_of_work pk nonce target then nonce
-    else loop (increment_nonce nonce) in
-  loop (random_nonce ())
+let generate_proof_of_work ?max pk target =
+  let may_interupt =
+    match max with
+    | None -> (fun _ -> ())
+    | Some max -> (fun cpt -> if max < cpt then raise Not_found) in
+  let rec loop nonce cpt =
+    may_interupt cpt ;
+    if check_proof_of_work pk nonce target then
+      nonce
+    else
+      loop (increment_nonce nonce) (cpt + 1) in
+  loop (random_nonce ()) 0
 
 let public_key_encoding =
   let open Data_encoding in
diff --git a/src/utils/crypto_box.mli b/src/utils/crypto_box.mli
index 0ae416919..cbeedd440 100644
--- a/src/utils/crypto_box.mli
+++ b/src/utils/crypto_box.mli
@@ -38,5 +38,5 @@ val fast_box        : channel_key -> MBytes.t -> nonce -> MBytes.t
 val fast_box_open   : channel_key -> MBytes.t -> nonce -> MBytes.t option
 
 val check_proof_of_work : public_key -> nonce -> target -> bool
-val generate_proof_of_work : public_key -> target -> nonce
+val generate_proof_of_work : ?max:int -> public_key -> target -> nonce