model/credentials: support legacy env vars; support .env-style credential files

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I231c5f28d7313ed44c252aaedab2becc6a6a6964

src/model/credentials.rs

@@ -132,10 +132,34 @@ impl PakkerCompatCredentialsFile {
       ))
     })?;
 
-    serde_json::from_str(&content).map_err(|e| {
-      PakkerError::InternalError(format!(
-        "Failed to parse Pakku credentials file: {e}"
-      ))
+    // Try JSON first (for compatibility with future format changes)
+    if let Ok(parsed) = serde_json::from_str::<Self>(&content) {
+      return Ok(parsed);
+    }
+
+    // Fall back to .env-style key=value parsing (format written by pakker init)
+    let mut curseforge_api_key = None;
+    let mut github_access_token = None;
+
+    for line in content.lines() {
+      let line = line.trim();
+      if line.is_empty() || line.starts_with('#') {
+        continue;
+      }
+      if let Some((key, value)) = line.split_once('=') {
+        let key = key.trim();
+        let value = value.trim().to_string();
+        match key {
+          "CURSEFORGE_API_KEY" => curseforge_api_key = Some(value),
+          "GITHUB_TOKEN" => github_access_token = Some(value),
+          _ => {},
+        }
+      }
+    }
+
+    Ok(Self {
+      curseforge_api_key,
+      github_access_token,
     })
   }
 }
@@ -160,8 +184,9 @@ impl ResolvedCredentials {
     let pakku_file = PakkerCompatCredentialsFile::load().ok();
 
     Self {
-      curseforge_api_key:  resolve_secret(
+      curseforge_api_key:  resolve_secret_with_fallback(
         "PAKKER_CURSEFORGE_API_KEY",
+        "CURSEFORGE_API_KEY",
         "curseforge_api_key",
         pakker_file
           .as_ref()
@@ -176,8 +201,9 @@ impl ResolvedCredentials {
         pakker_file.as_ref().and_then(|f| f.modrinth_token.clone()),
         None,
       ),
-      github_access_token: resolve_secret(
+      github_access_token: resolve_secret_with_fallback(
         "PAKKER_GITHUB_TOKEN",
+        "GITHUB_TOKEN",
         "github_access_token",
         pakker_file
           .as_ref()
@@ -248,6 +274,40 @@ fn resolve_secret(
     .map(|v| (v, CredentialsSource::PakkerFile))
 }
 
+fn resolve_secret_with_fallback(
+  env_key: &str,
+  fallback_env_key: &str,
+  keyring_entry: &str,
+  pakker_file_value: Option<String>,
+  pakku_file_value: Option<String>,
+) -> Option<(String, CredentialsSource)> {
+  if let Ok(v) = std::env::var(env_key)
+    && !v.trim().is_empty()
+  {
+    return Some((v.trim().to_string(), CredentialsSource::Env));
+  }
+
+  if let Ok(v) = std::env::var(fallback_env_key)
+    && !v.trim().is_empty()
+  {
+    return Some((v.trim().to_string(), CredentialsSource::Env));
+  }
+
+  if let Ok(v) = get_keyring_secret(keyring_entry)
+    && !v.trim().is_empty()
+  {
+    return Some((v.trim().to_string(), CredentialsSource::Keyring));
+  }
+
+  if let Some(v) = pakker_file_value.filter(|v| !v.trim().is_empty()) {
+    return Some((v, CredentialsSource::PakkerFile));
+  }
+
+  pakku_file_value
+    .filter(|v| !v.trim().is_empty())
+    .map(|v| (v, CredentialsSource::PakkerFile))
+}
+
 fn get_keyring_secret(
   entry: &str,
 ) -> std::result::Result<String, keyring::Error> {