imlement native csv loader

3 files changed, 79 insertions, 0 deletions

diff --git a/src/sheet/loader/mod.rs b/src/sheet/loader/mod.rs
new file mode 100644
index 0000000..0e083fe
--- /dev/null
+++ b/src/sheet/loader/mod.rs
@@ -0,0 +1,58 @@
+use std::{collections::HashMap, path::Path, ptr::addr_of_mut};
+
+use mlua::{Lua, UserData};
+use once_cell::sync::Lazy;
+
+use crate::lua::{ownedfunction::OwnedFunction, runnable::Runnable};
+
+use self::native::csv::load_csv;
+
+use super::{register::SheetId, tablized::Tablized};
+
+pub mod native;
+
+#[derive(Default)]
+pub struct Loader {
+    loaders: HashMap<String, Box<dyn Runnable<String, Tablized>>>,
+}
+
+impl Loader {
+    pub fn new() -> Self {
+        let mut loaders: HashMap<String, Box<dyn Runnable<String, Tablized>>> = HashMap::new();
+
+        loaders.insert("csv".to_string(), Box::new(load_csv));
+
+        Self { loaders }
+    }
+
+    pub fn load_sheet(&self, path: String, lua: &Lua) -> Option<SheetId> {
+        let p = Path::new(&path);
+        if p.is_file() {
+            let loader = self.loaders.get(p.extension()?.to_str()?)?;
+            return match loader.run(path, lua) {
+                Ok(table) => table.to_sheet(lua).ok(),
+                Err(_) => None,
+            };
+        }
+
+        return None;
+    }
+
+    pub fn add(&mut self, extension: String, func: Box<dyn Runnable<String, Tablized>>) {
+        self.loaders.insert(extension, func);
+    }
+
+    pub fn get() -> &'static mut Self {
+        static mut GLOBAL_LOADER: Lazy<Loader> = Lazy::new(|| Loader::new());
+        unsafe { &mut *addr_of_mut!(GLOBAL_LOADER) }
+    }
+}
+
+impl UserData for Loader {
+    fn add_methods<'lua, M: mlua::prelude::LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
+        methods.add_function("add", |_, (extension, func): (String, OwnedFunction)| {
+            Loader::get().add(extension, Box::new(func));
+            Ok(())
+        });
+    }
+}
diff --git a/src/sheet/loader/native/csv.rs b/src/sheet/loader/native/csv.rs
new file mode 100644
index 0000000..4a8f05d
--- /dev/null
+++ b/src/sheet/loader/native/csv.rs
@@ -0,0 +1,19 @@
+use std::{fs::File, io::BufReader};
+
+use crate::sheet::{cell::Cell, tablized::Tablized};
+
+pub fn load_csv(path: String) -> Tablized {
+    let file = File::open(path).unwrap();
+    let reader = BufReader::new(file);
+    let mut csv_reader = csv::Reader::from_reader(reader);
+
+    let mut table = Vec::new();
+
+    for result in csv_reader.records() {
+        if let Ok(record) = result {
+            table.push(record.iter().map(|s| Cell::from(s)).collect::<Vec<Cell>>())
+        }
+    }
+
+    Tablized::Vector(table)
+}
diff --git a/src/sheet/loader/native/mod.rs b/src/sheet/loader/native/mod.rs
new file mode 100644
index 0000000..41ec797
--- /dev/null
+++ b/src/sheet/loader/native/mod.rs
@@ -0,0 +1,2 @@
+
+pub mod csv;