Add parsing of minecraft version manifest

src-tauri/src/launcher/mod.rs

@@ -0,0 +1,82 @@
+use std::fmt::Display;
+
+use anyhow::{Result, bail, anyhow};
+use reqwest::Client;
+use serde_json::{Value, Map};
+
+
+
+async fn get_version_manifest(reqwest: &Client) -> Result<Value> {
+    let received: Value = reqwest
+    .get("https://piston-meta.mojang.com/mc/game/version_manifest_v2.json")
+    .send()
+    .await?
+    .json()
+    .await?;
+    Ok(received)
+}
+
+fn get_version_from_manifest<'a>(manifest: &'a Value, game_version: String, version_type: &VersionType) -> Result<&'a Map<String, Value>> {
+    let versions = manifest.get("versions").ok_or(anyhow!("Manifest format is invalid"))?;
+    let arr = versions.as_array().ok_or(anyhow!("Manifest format is invalid"))?;
+    for i in arr.iter().enumerate() {
+        let map = i.1.as_object().ok_or(anyhow!("Manifest format is invalid"))?;
+        let id = map.get("id").ok_or(anyhow!("Manifest format is invalid, cannot find version id"))?;
+        let id = id.as_str().ok_or(anyhow!("Manifest format is invalid, id is not a str"))?;
+        let v_type = map.get("type").ok_or(anyhow!("Manifest format is invalid, cannot find version type"))?;
+        let v_type = v_type.as_str().ok_or(anyhow!("Manifest format is invalid, type is not a str"))?;
+        if id == game_version && v_type.try_into() == Ok(version_type) {
+            return Ok(map);
+        }
+    }
+    bail!("Version not Found")
+}
+
+fn get_version_detail(reqwest: &Client, version : &Map<String, Value>) -> Result<()> {
+    bail!("Not implemented yet")
+}
+
+pub async fn download_assets(game_version: String, version_type: &VersionType) -> Result<()> {
+    let reqwest_client = Client::new();
+    let manifest = get_version_manifest(&reqwest_client).await?;
+    let version = get_version_from_manifest(&manifest, game_version, version_type)?;
+    Ok(())
+    
+    
+}
+
+#[derive(PartialEq)]
+pub enum VersionType {
+    Release,
+    Snapshot,
+    OldAlpha,
+    OldBeta,
+}
+
+impl<'a> TryInto<&'a VersionType> for &str {
+    type Error = ();
+
+    fn try_into(self) -> std::result::Result<&'a VersionType, Self::Error> {
+        match self {
+            "release" => Ok(&VersionType::Release),
+            "snapshot" => Ok(&VersionType::Snapshot),
+            "old_alpha" => Ok(&VersionType::OldAlpha),
+            "old_beta" => Ok(&VersionType::OldBeta),
+            _ => Err(()),
+        }
+    }
+
+    
+}
+
+impl Display for VersionType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let str = match self {
+            Self::Release => "release",
+            Self::Snapshot => "snapshot",
+            Self::OldAlpha => "old_alpha",
+            Self::OldBeta => "old_beta",
+        };
+        write!(f, "{}", str)
+    }
+}

src-tauri/src/main.rs

@@ -4,6 +4,7 @@
 )]
 
 pub mod authentification;
+pub mod launcher;
 
 use authentification::{Authentification, Prompt};
 use anyhow::Result;