feat: in-game theme store — server catalog + verified downloads + install UI

Phase 1+2 of the theme-store roadmap: a free catalog served by solitaire_server and an in-app browse/install flow, making custom themes installable on Android for the first time (the manual drop-a-zip flow can't reach the app-private themes dir there). - solitaire_sync: ThemeCatalogEntry/ThemeCatalogResponse wire types (additive module; SyncPayload and SyncProvider untouched) - solitaire_server: THEME_STORE_DIR scan at startup (meta-only theme.ron parse, sha256, 20 MiB cap, best-effort per archive); public GET /api/themes, /api/themes/{id}/download, /{id}/preview; compose volume + README_SERVER docs - solitaire_data: ThemeStoreClient — catalog fetch + download with mandatory size/sha256 verification before bytes are released - solitaire_engine: ThemeStorePlugin — 'Browse theme store' button in Settings → Cosmetic, modal catalog (leaderboard-style rebuild), download on AsyncComputeTaskPool, atomic .tmp+rename write into user_theme_dir, then the existing hardened import_theme pipeline and an in-place registry refresh New deps: sha2 (workspace, server+data); ron/zip reused in server; serde_json added to solitaire_sync dev-deps for DTO round-trip tests. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-07 13:12:41 -07:00
parent 018b69285d
commit d87397b382
23 changed files with 1718 additions and 3 deletions
@@ -0,0 +1,366 @@
+//! Theme-store catalog and file-serving endpoints.
+//!
+//! The store is filesystem-driven: the operator drops theme `.zip`
+//! archives (the same format the engine's theme importer consumes)
+//! into the directory named by the `THEME_STORE_DIR` environment
+//! variable (default `theme_store/`), plus an optional `<id>.png`
+//! preview per theme. [`ThemeStore::scan`] runs once at startup —
+//! adding a theme means dropping the files and restarting the server.
+//!
+//! Endpoints (all public, no auth — the catalog is free):
+//!
+//! - `GET /api/themes` — [`ThemeCatalogResponse`] JSON
+//! - `GET /api/themes/{id}/download` — the theme `.zip`
+//! - `GET /api/themes/{id}/preview` — the preview PNG (404 when absent)
+
+use std::collections::HashMap;
+use std::io::{Cursor, Read};
+use std::path::{Path, PathBuf};
+
+use axum::Json;
+use axum::extract::{Path as UrlPath, State};
+use axum::http::header;
+use axum::response::{IntoResponse, Response};
+use serde::Deserialize;
+use sha2::{Digest, Sha256};
+use solitaire_sync::{ThemeCatalogEntry, ThemeCatalogResponse};
+use tracing::{info, warn};
+
+use crate::AppState;
+use crate::error::AppError;
+
+/// Environment variable naming the theme-store directory.
+pub const THEME_STORE_DIR_ENV: &str = "THEME_STORE_DIR";
+
+/// Default theme-store directory, relative to the server working dir —
+/// same convention as the `avatars/` upload directory.
+pub const DEFAULT_THEME_STORE_DIR: &str = "theme_store";
+
+/// Archives larger than this are skipped at scan time with a warning.
+/// Mirrors the engine importer's `MAX_ARCHIVE_BYTES` (20 MiB) — a zip
+/// whose *compressed* size already exceeds the client's uncompressed
+/// limit can never import, so serving it only wastes bandwidth.
+pub const MAX_STORE_ARCHIVE_BYTES: u64 = 20 * 1024 * 1024;
+
+/// Upper bound on the bytes read out of an archive's `theme.ron`
+/// entry at scan time, guarding the catalog scan against a
+/// zip-bombed manifest. Real manifests are a few KB.
+const MAX_MANIFEST_BYTES: u64 = 1024 * 1024;
+
+/// `theme.ron`'s outer shape, `meta` block only — the 53 face entries
+/// are irrelevant to the catalog and are validated client-side by the
+/// importer at install time.
+#[derive(Debug, Deserialize)]
+struct ManifestMetaOnly {
+    meta: StoreThemeMeta,
+}
+
+/// Mirror of the `meta` block of a theme manifest. The canonical
+/// definition is `solitaire_engine::theme::ThemeMeta`; the server
+/// cannot depend on the engine crate (it links Bevy), so the shape is
+/// re-declared here. Keep the two in lockstep.
+#[derive(Debug, Deserialize)]
+struct StoreThemeMeta {
+    id: String,
+    name: String,
+    author: String,
+    version: String,
+    card_aspect: (u32, u32),
+}
+
+/// In-memory catalog built by scanning the theme-store directory once
+/// at startup. Shared via [`AppState`].
+#[derive(Debug, Default)]
+pub struct ThemeStore {
+    entries: Vec<ThemeCatalogEntry>,
+    zip_paths: HashMap<String, PathBuf>,
+    preview_paths: HashMap<String, PathBuf>,
+}
+
+impl ThemeStore {
+    /// An empty store — used by tests and when the store directory is
+    /// absent (the server runs fine without a theme store).
+    pub fn empty() -> Self {
+        Self::default()
+    }
+
+    /// Scans `dir` for `*.zip` theme archives and builds the catalog.
+    ///
+    /// Best-effort per archive: unreadable files, oversized archives,
+    /// missing/malformed manifests, and duplicate ids are skipped with
+    /// a warning rather than failing startup — one bad upload must not
+    /// take the store (or the server) down.
+    pub fn scan(dir: &Path) -> Self {
+        let mut store = Self::default();
+        let read_dir = match std::fs::read_dir(dir) {
+            Ok(read_dir) => read_dir,
+            Err(e) => {
+                info!(
+                    "theme store: directory {} not readable ({e}); serving an empty catalog",
+                    dir.display()
+                );
+                return store;
+            }
+        };
+
+        let mut zips: Vec<PathBuf> = read_dir
+            .flatten()
+            .map(|entry| entry.path())
+            .filter(|path| path.extension().is_some_and(|ext| ext == "zip"))
+            .collect();
+        // Deterministic catalog regardless of directory iteration order.
+        zips.sort();
+
+        for zip_path in zips {
+            match scan_archive(&zip_path) {
+                Ok((meta, size_bytes, sha256)) => {
+                    if store.zip_paths.contains_key(&meta.id) {
+                        warn!(
+                            "theme store: skipping {} — duplicate theme id {:?}",
+                            zip_path.display(),
+                            meta.id
+                        );
+                        continue;
+                    }
+                    let preview_path = dir.join(format!("{}.png", meta.id));
+                    let preview_url = if preview_path.is_file() {
+                        store.preview_paths.insert(meta.id.clone(), preview_path);
+                        Some(format!("/api/themes/{}/preview", meta.id))
+                    } else {
+                        None
+                    };
+                    store.entries.push(ThemeCatalogEntry {
+                        download_url: format!("/api/themes/{}/download", meta.id),
+                        preview_url,
+                        id: meta.id.clone(),
+                        name: meta.name,
+                        author: meta.author,
+                        version: meta.version,
+                        card_aspect: meta.card_aspect,
+                        size_bytes,
+                        sha256,
+                    });
+                    store.zip_paths.insert(meta.id, zip_path);
+                }
+                Err(reason) => {
+                    warn!("theme store: skipping {} — {reason}", zip_path.display());
+                }
+            }
+        }
+
+        store.entries.sort_by(|a, b| a.name.cmp(&b.name));
+        info!("theme store: serving {} theme(s)", store.entries.len());
+        store
+    }
+
+    /// Catalog entries, sorted by display name.
+    pub fn entries(&self) -> &[ThemeCatalogEntry] {
+        &self.entries
+    }
+}
+
+/// Reads one archive: enforces the size cap, hashes the bytes, and
+/// extracts + validates the manifest's `meta` block.
+fn scan_archive(zip_path: &Path) -> Result<(StoreThemeMeta, u64, String), String> {
+    let size_bytes = std::fs::metadata(zip_path)
+        .map_err(|e| format!("cannot stat: {e}"))?
+        .len();
+    if size_bytes > MAX_STORE_ARCHIVE_BYTES {
+        return Err(format!(
+            "{size_bytes} bytes exceeds the {MAX_STORE_ARCHIVE_BYTES}-byte store limit"
+        ));
+    }
+
+    let bytes = std::fs::read(zip_path).map_err(|e| format!("cannot read: {e}"))?;
+    let sha256 = hex_digest(&bytes);
+
+    let mut archive =
+        zip::ZipArchive::new(Cursor::new(bytes)).map_err(|e| format!("not a zip archive: {e}"))?;
+    let manifest_bytes = {
+        let entry = archive
+            .by_name("theme.ron")
+            .map_err(|e| format!("no theme.ron in archive: {e}"))?;
+        let mut buf = Vec::new();
+        entry
+            .take(MAX_MANIFEST_BYTES)
+            .read_to_end(&mut buf)
+            .map_err(|e| format!("cannot read theme.ron: {e}"))?;
+        buf
+    };
+
+    let parsed: ManifestMetaOnly =
+        ron::de::from_bytes(&manifest_bytes).map_err(|e| format!("malformed theme.ron: {e}"))?;
+    let meta = parsed.meta;
+    if meta.id.is_empty() {
+        return Err("theme id is empty".to_string());
+    }
+    if meta.id.contains('/') || meta.id.contains('\\') || meta.id.contains("..") {
+        return Err(format!("theme id {:?} is not filesystem-safe", meta.id));
+    }
+    if meta.card_aspect.0 == 0 || meta.card_aspect.1 == 0 {
+        return Err("card_aspect contains a zero".to_string());
+    }
+    Ok((meta, size_bytes, sha256))
+}
+
+/// Lowercase-hex SHA-256 of `bytes`.
+fn hex_digest(bytes: &[u8]) -> String {
+    let digest = Sha256::digest(bytes);
+    let mut out = String::with_capacity(digest.len() * 2);
+    for byte in digest {
+        out.push_str(&format!("{byte:02x}"));
+    }
+    out
+}
+
+/// `GET /api/themes` — the full catalog.
+pub async fn list(State(state): State<AppState>) -> Json<ThemeCatalogResponse> {
+    Json(ThemeCatalogResponse {
+        themes: state.theme_store.entries().to_vec(),
+    })
+}
+
+/// `GET /api/themes/{id}/download` — the theme archive bytes.
+pub async fn download(
+    State(state): State<AppState>,
+    UrlPath(id): UrlPath<String>,
+) -> Result<Response, AppError> {
+    let path = state
+        .theme_store
+        .zip_paths
+        .get(&id)
+        .ok_or_else(|| AppError::NotFound("theme not found".into()))?;
+    let bytes = tokio::fs::read(path)
+        .await
+        .map_err(|e| AppError::Internal(format!("theme archive unreadable: {e}")))?;
+    Ok((
+        [
+            (header::CONTENT_TYPE, "application/zip".to_string()),
+            (
+                header::CONTENT_DISPOSITION,
+                format!("attachment; filename=\"{id}.zip\""),
+            ),
+        ],
+        bytes,
+    )
+        .into_response())
+}
+
+/// `GET /api/themes/{id}/preview` — the preview PNG, when the store
+/// ships one for this theme.
+pub async fn preview(
+    State(state): State<AppState>,
+    UrlPath(id): UrlPath<String>,
+) -> Result<Response, AppError> {
+    let path = state
+        .theme_store
+        .preview_paths
+        .get(&id)
+        .ok_or_else(|| AppError::NotFound("theme preview not found".into()))?;
+    let bytes = tokio::fs::read(path)
+        .await
+        .map_err(|e| AppError::Internal(format!("theme preview unreadable: {e}")))?;
+    Ok(([(header::CONTENT_TYPE, "image/png".to_string())], bytes).into_response())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::io::Write;
+
+    /// Minimal valid manifest for id/name pairs — the scan only reads
+    /// the `meta` block, so no face entries are needed.
+    fn manifest(id: &str, name: &str) -> String {
+        format!(
+            r#"(
+    meta: (
+        id: "{id}",
+        name: "{name}",
+        author: "Test Author",
+        version: "1.0.0",
+        card_aspect: (2, 3),
+    ),
+    faces: {{}},
+    back: "back.svg",
+)"#
+        )
+    }
+
+    fn write_zip(dir: &Path, file_name: &str, manifest: &str) -> PathBuf {
+        let path = dir.join(file_name);
+        let file = std::fs::File::create(&path).expect("create zip");
+        let mut writer = zip::ZipWriter::new(file);
+        let options = zip::write::SimpleFileOptions::default();
+        writer.start_file("theme.ron", options).expect("start");
+        writer.write_all(manifest.as_bytes()).expect("write");
+        writer.finish().expect("finish");
+        path
+    }
+
+    #[test]
+    fn scan_of_missing_dir_yields_empty_catalog() {
+        let store = ThemeStore::scan(Path::new("/nonexistent/theme/store"));
+        assert!(store.entries().is_empty());
+    }
+
+    #[test]
+    fn scan_builds_sorted_catalog_with_hashes() {
+        let dir = tempfile::tempdir().expect("tempdir");
+        let zebra = write_zip(dir.path(), "b.zip", &manifest("zebra", "Zebra"));
+        write_zip(dir.path(), "a.zip", &manifest("aurora", "Aurora"));
+
+        let store = ThemeStore::scan(dir.path());
+        let entries = store.entries();
+        assert_eq!(entries.len(), 2);
+        // Sorted by display name, not filename.
+        assert_eq!(entries[0].id, "aurora");
+        assert_eq!(entries[1].id, "zebra");
+        assert_eq!(entries[1].download_url, "/api/themes/zebra/download");
+        assert_eq!(entries[1].preview_url, None);
+
+        let zebra_bytes = std::fs::read(&zebra).expect("read zip");
+        assert_eq!(entries[1].sha256, hex_digest(&zebra_bytes));
+        assert_eq!(entries[1].size_bytes, zebra_bytes.len() as u64);
+    }
+
+    #[test]
+    fn scan_picks_up_preview_png_keyed_by_theme_id() {
+        let dir = tempfile::tempdir().expect("tempdir");
+        write_zip(dir.path(), "neon.zip", &manifest("neon", "Neon"));
+        std::fs::write(dir.path().join("neon.png"), b"png-bytes").expect("write png");
+
+        let store = ThemeStore::scan(dir.path());
+        assert_eq!(
+            store.entries()[0].preview_url.as_deref(),
+            Some("/api/themes/neon/preview")
+        );
+        assert!(store.preview_paths.contains_key("neon"));
+    }
+
+    #[test]
+    fn scan_skips_duplicate_ids_and_keeps_first() {
+        let dir = tempfile::tempdir().expect("tempdir");
+        write_zip(dir.path(), "1_first.zip", &manifest("dupe", "First"));
+        write_zip(dir.path(), "2_second.zip", &manifest("dupe", "Second"));
+
+        let store = ThemeStore::scan(dir.path());
+        assert_eq!(store.entries().len(), 1);
+        assert_eq!(store.entries()[0].name, "First");
+    }
+
+    #[test]
+    fn scan_skips_malformed_and_unsafe_manifests() {
+        let dir = tempfile::tempdir().expect("tempdir");
+        // Not a zip at all.
+        std::fs::write(dir.path().join("junk.zip"), b"not a zip").expect("write");
+        // Path-separator id must be rejected — it would become a URL
+        // path segment and a client install directory name.
+        write_zip(dir.path(), "evil.zip", &manifest("../evil", "Evil"));
+        // Valid one to prove the scan carries on past failures.
+        write_zip(dir.path(), "ok.zip", &manifest("ok", "Ok"));
+
+        let store = ThemeStore::scan(dir.path());
+        assert_eq!(store.entries().len(), 1);
+        assert_eq!(store.entries()[0].id, "ok");
+    }
+}