feat: Takeout CSV, Atom feed, yt-dlp progress, and SQLite layers

37 unit tests covering the three parsers and the database, including
that a feed refresh preserves download state and that a truncated
feed response fails rather than storing partial results.

src-tauri/src/models.rs

@@ -0,0 +1,104 @@
+use serde::{Deserialize, Serialize};
+
+/// A YouTube channel the user is subscribed to, as imported from Takeout.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Channel {
+    pub id: String,
+    pub title: String,
+    pub url: String,
+}
+
+/// A video as described by a channel's public Atom feed.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct Video {
+    pub id: String,
+    pub channel_id: String,
+    pub title: String,
+    pub description: String,
+    /// Unix seconds, so feed ordering is a plain indexed sort.
+    pub published: i64,
+    pub thumb_url: String,
+    pub views: i64,
+    pub is_short: bool,
+}
+
+/// A channel plus how many of its videos we currently know about.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ChannelWithCount {
+    pub id: String,
+    pub title: String,
+    pub url: String,
+    pub video_count: i64,
+    pub downloaded_count: i64,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum DownloadState {
+    Queued,
+    Running,
+    Done,
+    Failed,
+    Cancelled,
+}
+
+impl DownloadState {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            DownloadState::Queued => "queued",
+            DownloadState::Running => "running",
+            DownloadState::Done => "done",
+            DownloadState::Failed => "failed",
+            DownloadState::Cancelled => "cancelled",
+        }
+    }
+
+    pub fn from_str(s: &str) -> Option<Self> {
+        match s {
+            "queued" => Some(DownloadState::Queued),
+            "running" => Some(DownloadState::Running),
+            "done" => Some(DownloadState::Done),
+            "failed" => Some(DownloadState::Failed),
+            "cancelled" => Some(DownloadState::Cancelled),
+            _ => None,
+        }
+    }
+}
+
+/// A feed row: video metadata joined with whatever we know about its download.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FeedItem {
+    pub id: String,
+    pub channel_id: String,
+    pub channel_title: String,
+    pub title: String,
+    pub description: String,
+    pub published: i64,
+    pub thumb_url: String,
+    pub thumb_path: Option<String>,
+    pub views: i64,
+    pub is_short: bool,
+    pub state: Option<DownloadState>,
+    pub path: Option<String>,
+    pub pct: Option<f64>,
+    pub error: Option<String>,
+}
+
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+pub struct FeedFilter {
+    pub channel_id: Option<String>,
+    pub search: Option<String>,
+    #[serde(default)]
+    pub downloaded_only: bool,
+    #[serde(default)]
+    pub hide_shorts: bool,
+    pub limit: Option<i64>,
+}
+
+/// Result of checking that the external binaries we shell out to exist.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Prereqs {
+    pub yt_dlp: Option<String>,
+    pub ffmpeg: Option<String>,
+    pub library_path: String,
+}