From 9cee703e73b1c5fc00411b406dfe04bbe7189ca7 Mon Sep 17 00:00:00 2001
From: Miguel Molina <miguel@erizocosmi.co>
Date: Mon, 8 Jan 2018 18:08:57 +0100
Subject: [PATCH] wip: implement writeFile and writeFileSync

Signed-off-by: Miguel Molina <miguel@erizocosmi.co>
---
 src/fs.re          | 36 +++++++++++++++++++++++++++++++++---
 src/fs.rei         | 38 +++++++++++++++++---------------------
 src/renodeUtils.re |  5 +++++
 3 files changed, 55 insertions(+), 24 deletions(-)

diff --git a/src/fs.re b/src/fs.re
index 76ef09b..e179ad6 100644
--- a/src/fs.re
+++ b/src/fs.re
@@ -168,6 +168,36 @@ let writeString = (~fd, ~string, ~offset, ~length) =>
 let writeStringSync = (~fd, ~string, ~offset, ~length) =>
   Unix.write_substring(fd, string, offset, length);
 
-let writeFile = (~file, ~data, ~options) => ();
-
-let writeFileSync = (~file, ~data, ~options) => ();
\ No newline at end of file
+type writeFileOptions = {
+  encoding: option(string),
+  mode: option(asyncFilePerm),
+  flags: list(asyncOpenFlag)
+};
+
+let defaultWriteFileFlags = [Unix.O_CREAT, Unix.O_TRUNC];
+
+let writeFile = (~options={encoding: None, mode: None, flags: []}, ~file, ~data) => {
+  let flags = List.length(options.flags) < 1 ? defaultWriteFileFlags : options.flags;
+  let mode = RenodeUtils.withDefault(options.mode, ~default=438);
+  Lwt.bind(
+    Lwt_unix.openfile(file, flags, mode),
+    fd => Lwt.bind(
+      write(fd, data, 0, Bytes.length(data)),
+      (_) => close(fd)
+    )
+  )
+};
+
+type writeFileSyncOptions = {
+  encoding: option(string),
+  mode: option(syncFilePerm),
+  flags: list(syncOpenFlag)
+};
+
+let writeFileSync = (~options={encoding: None, mode: None, flags: []}, ~file, ~data) => {
+  let flags = List.length(options.flags) < 1 ? defaultWriteFileFlags : options.flags;
+  let mode = RenodeUtils.withDefault(options.mode, ~default=438);
+  let fd = Unix.openfile(file, flags, mode);
+  let _ = writeSync(fd, data, 0, Bytes.length(data));
+  closeSync(fd);
+};
\ No newline at end of file
diff --git a/src/fs.rei b/src/fs.rei
index 6cce62f..f3b368b 100644
--- a/src/fs.rei
+++ b/src/fs.rei
@@ -363,24 +363,20 @@ let writeString:
 let writeStringSync:
   (~fd: syncFileDescr, ~string: string, ~offset: int, ~length: int) => int;
 
-[@ocaml.deprecated
-  {|
-    Fs.writeFile has yet to be implemented.
-    Please open a Work-In-Progress pull request if you are interested in contributing.
-    We will help answer questions and push you in the right direction.
-
-    Repo URL: https://github.com/kennetpostigo/lwt-node
-  |}
-]
-let writeFile: (~file: 'a, ~data: 'b, ~options: 'c) => unit;
-
-[@ocaml.deprecated
-  {|
-    Fs.writeFileSync has yet to be implemented.
-    Please open a Work-In-Progress pull request if you are interested in contributing.
-    We will help answer questions and push you in the right direction.
-
-    Repo URL: https://github.com/kennetpostigo/lwt-node
-  |}
-]
-let writeFileSync: (~file: 'a, ~data: 'b, ~options: 'c) => unit;
\ No newline at end of file
+type writeFileOptions = {
+  encoding: option(string),
+  mode: option(asyncFilePerm),
+  flags: list(asyncOpenFlag)
+};
+
+let writeFile:
+  (~options: writeFileOptions=?, ~file: string, ~data: bytes) => Node.t(unit);
+
+type writeFileSyncOptions = {
+  encoding: option(string),
+  mode: option(syncFilePerm),
+  flags: list(syncOpenFlag)
+};
+
+let writeFileSync:
+  (~options: writeFileSyncOptions=?, ~file: string, ~data: bytes) => unit;
\ No newline at end of file
diff --git a/src/renodeUtils.re b/src/renodeUtils.re
index 6a744a5..e300dd4 100644
--- a/src/renodeUtils.re
+++ b/src/renodeUtils.re
@@ -157,4 +157,9 @@ let iterPathUntil = (~condition, ~list, ~f) => {
     f(arr[position^], position, ! (position^ > (-1)));
     position := position^ - 1;
   };
+};
+
+let withDefault = (opt, ~default) => switch opt {
+| Some(v) => v
+| None => default
 };
\ No newline at end of file