From f72100b83d79e929e1952dbcb757dca47708a37e Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Tue, 10 Aug 2021 14:59:35 -0500
Subject: [PATCH] feat: Help write decoders/encoders

---
 src/encoded.rs |  8 ++++++--
 src/error.rs   | 20 ++++++++++++++++++++
 src/lib.rs     | 21 +++++++++++++++++++++
 3 files changed, 47 insertions(+), 2 deletions(-)
 create mode 100644 src/error.rs

diff --git a/src/encoded.rs b/src/encoded.rs
index fc013ba..ba79d78 100644
--- a/src/encoded.rs
+++ b/src/encoded.rs
@@ -7,8 +7,12 @@ pub enum Encoded {
 }
 
 impl Encoded {
-    pub fn from_slice(v: &[u8]) -> Result<Self, serde_json::Error> {
-        serde_json::from_slice(v)
+    pub fn from_slice(v: &[u8]) -> Result<Self, crate::Error> {
+        serde_json::from_slice(v).map_err(|e| crate::Error::new(e.to_string()))
+    }
+
+    pub fn to_string_pretty(&self) -> Result<String, crate::Error> {
+        serde_json::to_string_pretty(self).map_err(|e| crate::Error::new(e.to_string()))
     }
 }
 
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..e464738
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,20 @@
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Error {
+    message: String,
+}
+
+impl Error {
+    pub fn new(message: impl ToString) -> Self {
+        Self {
+            message: message.to_string(),
+        }
+    }
+}
+
+impl std::fmt::Display for Error {
+    fn fmt(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
+        self.message.fmt(formatter)
+    }
+}
+
+impl std::error::Error for Error {}
diff --git a/src/lib.rs b/src/lib.rs
index 2bd3a8a..dffd25b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1 +1,22 @@
+use std::io::Read;
+use std::io::Write;
+
+mod error;
+
 pub mod encoded;
+pub use error::Error;
+
+pub fn encoder_in() -> Result<encoded::Encoded, Error> {
+    let mut buf = Vec::new();
+    std::io::stdin()
+        .read_to_end(&mut buf)
+        .map_err(|e| crate::Error::new(e.to_string()))?;
+    encoded::Encoded::from_slice(&buf)
+}
+
+pub fn decoder_output(e: encoded::Encoded) -> Result<(), Error> {
+    let s = e.to_string_pretty()?;
+    std::io::stdout()
+        .write_all(s.as_bytes())
+        .map_err(|e| crate::Error::new(e.to_string()))
+}