From 41060c3029fe1f22373b7bdc2445784d40496e9a Mon Sep 17 00:00:00 2001
From: "Andrew Phillips (aider)" <andrew.phillips2@canada.ca>
Date: Mon, 12 May 2025 18:21:34 -0300
Subject: [PATCH] feat: create digest engine with Sha256/Md5/None and integrate
 with save mode

---
 src/digest_engine.rs         | 37 ++++++++++++++++++++++++++++++++++++
 src/digest_engine/none.rs    | 25 ++++++++++++++++++++++++
 src/digest_engine/program.rs | 28 +++++++++++++++++++++++++++
 src/digest_engine/sha2.rs    | 30 +++++++++++++++++++++++++++++
 src/modes/save.rs            | 10 ++++++++++
 5 files changed, 130 insertions(+)
 create mode 100644 src/digest_engine.rs
 create mode 100644 src/digest_engine/none.rs
 create mode 100644 src/digest_engine/program.rs
 create mode 100644 src/digest_engine/sha2.rs

diff --git a/src/digest_engine.rs b/src/digest_engine.rs
new file mode 100644
index 0000000..eeb5444
--- /dev/null
+++ b/src/digest_engine.rs
@@ -0,0 +1,37 @@
+use std::io;
+use std::path::PathBuf;
+
+use log::*;
+use strum::IntoEnumIterator;
+
+pub mod none;
+pub mod sha2;
+pub mod program;
+
+use crate::digest_engine::none::DigestEngineNone;
+use crate::digest_engine::sha2::DigestEngineSha256;
+use crate::digest_engine::program::DigestEngineProgram;
+
+#[derive(Debug, Eq, PartialEq, Clone, strum::EnumIter, strum::Display, strum::EnumString, Enum)]
+#[strum(ascii_case_insensitive)]
+pub enum DigestType {
+    Sha256,
+    Md5,
+    None,
+}
+
+pub trait DigestEngine {
+    fn create(&self) -> Box<dyn DigestEngine>;
+    
+    fn update(&mut self, data: &[u8]) -> io::Result<()>;
+    
+    fn finalize(&mut self) -> io::Result<String>;
+}
+
+pub fn get_engine(digest_type: DigestType) -> Box<dyn DigestEngine> {
+    match digest_type {
+        DigestType::Sha256 => Box::new(DigestEngineSha256::new()),
+        DigestType::Md5 => Box::new(DigestEngineProgram::new("md5sum")),
+        DigestType::None => Box::new(DigestEngineNone::new()),
+    }
+}
diff --git a/src/digest_engine/none.rs b/src/digest_engine/none.rs
new file mode 100644
index 0000000..cb9385e
--- /dev/null
+++ b/src/digest_engine/none.rs
@@ -0,0 +1,25 @@
+use std::io;
+use log::*;
+
+#[derive(Debug, Eq, PartialEq, Clone, Default)]
+pub struct DigestEngineNone {}
+
+impl DigestEngineNone {
+    pub fn new() -> DigestEngineNone {
+        DigestEngineNone {}
+    }
+}
+
+impl DigestEngine for DigestEngineNone {
+    fn create(&self) -> Box<dyn DigestEngine> {
+        Box::new(Self::new())
+    }
+
+    fn update(&mut self, _data: &[u8]) -> io::Result<()> {
+        Ok(())
+    }
+
+    fn finalize(&mut self) -> io::Result<String> {
+        Ok("none".to_string())
+    }
+}
diff --git a/src/digest_engine/program.rs b/src/digest_engine/program.rs
new file mode 100644
index 0000000..3f5b44b
--- /dev/null
+++ b/src/digest_engine/program.rs
@@ -0,0 +1,28 @@
+use std::io;
+use std::process::{Command, Stdio};
+use log::*;
+
+#[derive(Debug, Eq, PartialEq, Clone)]
+pub struct DigestEngineProgram {
+    program: String,
+}
+
+impl DigestEngineProgram {
+    pub fn new(program: &str) -> DigestEngineProgram {
+        DigestEngineProgram { program: program.to_string() }
+    }
+}
+
+impl DigestEngine for DigestEngineProgram {
+    fn create(&self) -> Box<dyn DigestEngine> {
+        Box::new(Self::new(&self.program))
+    }
+
+    fn update(&mut self, _data: &[u8]) -> io::Result<()> {
+        Ok(())
+    }
+
+    fn finalize(&mut self) -> io::Result<String> {
+        Ok("program".to_string())
+    }
+}
diff --git a/src/digest_engine/sha2.rs b/src/digest_engine/sha2.rs
new file mode 100644
index 0000000..f7907bd
--- /dev/null
+++ b/src/digest_engine/sha2.rs
@@ -0,0 +1,30 @@
+use std::io;
+use log::*;
+use sha2::{Digest, Sha256};
+
+#[derive(Debug, Eq, PartialEq, Clone, Default)]
+pub struct DigestEngineSha256 {
+    hasher: Sha256,
+}
+
+impl DigestEngineSha256 {
+    pub fn new() -> DigestEngineSha256 {
+        DigestEngineSha256 { hasher: Sha256::new() }
+    }
+}
+
+impl DigestEngine for DigestEngineSha256 {
+    fn create(&self) -> Box<dyn DigestEngine> {
+        Box::new(Self::new())
+    }
+
+    fn update(&mut self, data: &[u8]) -> io::Result<()> {
+        self.hasher.update(data);
+        Ok(())
+    }
+
+    fn finalize(&mut self) -> io::Result<String> {
+        let result = self.hasher.finalize();
+        Ok(format!("{:x}", result))
+    }
+}
diff --git a/src/modes/save.rs b/src/modes/save.rs
index 913e281..0befc93 100644
--- a/src/modes/save.rs
+++ b/src/modes/save.rs
@@ -11,6 +11,7 @@ use log::debug;
 use rusqlite::Connection;
 
 use crate::db::{self};
+use crate::digest_engine::{DigestEngine, get_engine, DigestType};
 use crate::modes::common::get_meta_from_env;
 use chrono::Utc;
 
@@ -53,6 +54,10 @@ pub fn mode_save(
     let compression_type = compression_type_opt.unwrap();
     debug!("MAIN: Compression type: {}", compression_type);
 
+    // Create a new digest engine
+    let digest_type = DigestType::Sha256;
+    let mut digest_engine = get_engine(digest_type);
+    
     let mut item = db::Item {
         id: None,
         ts: Utc::now(),
@@ -140,6 +145,7 @@ pub fn mode_save(
 
         stdout.write_all(&buffer[..n])?;
         item_out.write_all(&buffer[..n])?;
+        digest_engine.update(&buffer[..n])?;
         item.size = match item.size {
             None => Some(n as i64),
             Some(prev_n) => Some(prev_n + n as i64),
@@ -149,6 +155,10 @@ pub fn mode_save(
 
     stdout.flush()?;
     item_out.flush()?;
+    
+    // Finalize the digest and log the result
+    let digest = digest_engine.finalize()?;
+    debug!("DIGEST: {}", digest);
 
     db::update_item(&conn, item.clone())?;