From 51cba3c68c69652dc09bde21c673f985cd7db51c Mon Sep 17 00:00:00 2001
From: kageru <kageru@encode.moe>
Date: Fri, 24 Jan 2020 00:02:32 +0100
Subject: [PATCH] Wip: persistent storage of list entries

---
 Cargo.toml   |  2 ++
 src/main.rs  |  7 +++++--
 src/tracc.rs | 35 ++++++++++++++++++++++++++---------
 3 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index e9b5503..78a91d8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,5 @@ edition = "2018"
 [dependencies]
 tui = "0.8.0"
 termion = "1.5"
+serde_json = "1"
+serde = { version = "1", features = ["derive"] }
diff --git a/src/main.rs b/src/main.rs
index b520d94..48111e9 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -20,7 +20,7 @@ fn main() -> Result<(), io::Error> {
     let mut inputs = io::stdin().keys();
     let backend = TermionBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
-    let mut tracc = Tracc::new();
+    let mut tracc = Tracc::open_or_create();
     terminal.hide_cursor()?;
     terminal.clear()?;
     loop {
@@ -29,7 +29,10 @@ fn main() -> Result<(), io::Error> {
         let input = inputs.next().unwrap().expect("input ded?");
         match tracc.mode {
             Mode::Normal => match input {
-                Key::Char('q') => break,
+                Key::Char('q') => {
+                    tracc.persist();
+                    break;
+                },
                 Key::Char('j') => tracc.selection_down(),
                 Key::Char('k') => tracc.selection_up(),
                 Key::Char('o') => {
diff --git a/src/tracc.rs b/src/tracc.rs
index d5b7018..4db36c7 100644
--- a/src/tracc.rs
+++ b/src/tracc.rs
@@ -1,5 +1,8 @@
 use super::Mode;
-use std::io;
+use serde::{Deserialize, Serialize};
+use serde_json::from_reader;
+use std::fs::File;
+use std::io::{self, BufReader, Write};
 use tui::backend::Backend;
 use tui::Terminal;
 
@@ -10,6 +13,7 @@ pub struct Tracc {
     pub mode: Mode,
 }
 
+#[derive(Serialize, Deserialize)]
 pub struct Todo {
     text: String,
     done: bool,
@@ -24,14 +28,19 @@ impl Todo {
     }
 }
 
+const JSON_PATH: &str = "tracc.json";
+
+fn read_todos() -> Option<Vec<Todo>> {
+    File::open(JSON_PATH)
+        .ok()
+        .map(|f| BufReader::new(f))
+        .and_then(|r| from_reader(r).ok())
+}
+
 impl Tracc {
-    pub fn new() -> Self {
+    pub fn open_or_create() -> Self {
         Self {
-            todos: vec![
-                Todo::new("This is a list entry"),
-                Todo::new("a second todo"),
-                Todo::new("And a third"),
-            ],
+            todos: read_todos().unwrap_or(vec![Todo::new("This is a list entry")]),
             selected: Some(0),
             mode: Mode::Normal,
         }
@@ -84,8 +93,8 @@ impl Tracc {
                 if self.current().text.is_empty() {
                     self.remove_current()
                 }
-                term.hide_cursor()? 
-            },
+                term.hide_cursor()?
+            }
         };
         self.mode = mode;
         Ok(())
@@ -98,4 +107,12 @@ impl Tracc {
     pub fn current_pop(&mut self) {
         self.todos[self.selected.unwrap()].text.pop();
     }
+
+    pub fn persist(self) {
+        let string = serde_json::to_string(&self.todos).unwrap();
+        std::fs::OpenOptions::new().create(true).write(true).open(JSON_PATH)
+            .ok()
+            .or_else(|| panic!("Can’t save todos to JSON. Dumping raw data:\n{}", string))
+            .map(|mut f| f.write(string.as_bytes()));
+    }
 }