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vissue_tui/
backend.rs

1//! Sync board facade shared by the file-backed and socket-backed clients.
2
3use vissue_core::config::Layout;
4use vissue_core::error::Error;
5use vissue_core::views::{
6    AgendaRow, ClaimRow, Excerpt, IssueDetail, ListQuery, RelatedHit, SearchHit, TreeNode,
7};
8
9/// Which store the board is talking to.
10#[derive(Debug, Clone, Copy, PartialEq, Eq)]
11pub enum BackendKind {
12    /// File-backed [`crate::CoreBackend`].
13    Core,
14    /// Socket-backed `ControlBackend`.
15    Control,
16}
17
18/// One page of list/ready rows.
19#[derive(Debug, Clone, Default)]
20pub struct ListPage {
21    /// Rows for this page. Empty when [`Self::unchanged`].
22    pub issues: Vec<vissue_core::views::IssueRow>,
23    /// Total issues in the catalog on serve; core repeats [`Self::matched`].
24    pub total: u64,
25    /// Rows that matched the query.
26    pub matched: u64,
27    /// Serve catalog revision. Core is 0.
28    pub revision: u64,
29    /// File-watcher generation.
30    pub generation: u64,
31    /// Serve says the catalog is unchanged since `since_revision`.
32    pub unchanged: bool,
33}
34
35/// Outcome of claim, note, or update.
36#[derive(Debug, Clone)]
37pub struct MutResult {
38    /// Mutation succeeded.
39    pub ok: bool,
40    /// Status text from the op. Core includes a trailing newline.
41    pub report: String,
42    /// Issue after the write, when the backend returns one.
43    pub issue: Option<IssueDetail>,
44    /// Serve revision after the write. Core is 0.
45    pub revision: u64,
46    /// File-watcher generation after the write.
47    pub generation: u64,
48}
49
50/// Fields `issue/update` accepts.
51#[derive(Debug, Clone, Default)]
52pub struct UpdateReq {
53    /// Issue to change.
54    pub id: String,
55    /// New org TODO state, if any.
56    pub state: Option<String>,
57    /// New priority letter, if any.
58    pub priority: Option<char>,
59    /// Blocker id to add.
60    pub block: Option<String>,
61    /// Blocker id to drop.
62    pub unblock: Option<String>,
63}
64
65/// Drops `since_revision` for one fetch after attach.
66#[derive(Debug)]
67pub struct SinceGate {
68    skip_once: std::sync::atomic::AtomicBool,
69}
70
71impl SinceGate {
72    /// After `initialize`, the next list must not send a core generation.
73    pub fn after_attach() -> Self {
74        Self {
75            skip_once: std::sync::atomic::AtomicBool::new(true),
76        }
77    }
78
79    /// Consume the skip flag, or return `Some(revision)` when `revision > 0`.
80    pub fn next(&self, revision: u64) -> Option<u64> {
81        if self
82            .skip_once
83            .swap(false, std::sync::atomic::Ordering::SeqCst)
84        {
85            None
86        } else if revision > 0 {
87            Some(revision)
88        } else {
89            None
90        }
91    }
92
93    /// Next list/ready must omit `since_revision` (pane or query changed).
94    pub fn invalidate(&self) {
95        self.skip_once
96            .store(true, std::sync::atomic::Ordering::SeqCst);
97    }
98}
99
100/// Read and mutate the board. Implementations are `CoreBackend` and
101/// `ControlBackend`.
102pub trait BoardBackend: Send + Sync + std::fmt::Debug {
103    /// Vault this backend reads and writes.
104    fn layout(&self) -> &Layout;
105    /// File-watcher generation.
106    fn generation(&self) -> u64;
107    /// Serve catalog revision. Core is always 0.
108    fn revision(&self) -> u64;
109    /// Which store this backend is.
110    fn live(&self) -> BackendKind;
111    /// Claim and update identity (core: constructor; control: serve `initialize`).
112    fn identity(&self) -> &str;
113
114    /// Filtered issue list for the List pane.
115    ///
116    /// # Errors
117    ///
118    /// Returns an error if the list cannot be loaded.
119    fn list(&self, q: ListQuery) -> Result<ListPage, Error>;
120    /// Actionable ready queue, optionally scoped to `project`.
121    ///
122    /// # Errors
123    ///
124    /// Returns an error if the ready list cannot be loaded.
125    fn ready(&self, project: Option<&str>) -> Result<ListPage, Error>;
126    /// Full metadata for one issue.
127    ///
128    /// # Errors
129    ///
130    /// Returns an error if the issue does not exist or cannot be fetched.
131    fn get(&self, id: &str) -> Result<IssueDetail, Error>;
132    /// On-disk heading range, capped and screened for secrets.
133    ///
134    /// # Errors
135    ///
136    /// Returns an error if the issue does not exist or its file cannot be read.
137    fn excerpt(&self, id: &str) -> Result<Excerpt, Error>;
138    /// Title and body search hits, capped at `limit`.
139    ///
140    /// # Errors
141    ///
142    /// Returns an error if search cannot run.
143    fn search(&self, query: &str, limit: usize) -> Result<Vec<SearchHit>, Error>;
144    /// Open claims, optionally filtered by holder and project.
145    ///
146    /// # Errors
147    ///
148    /// Returns an error if claims cannot be listed.
149    fn claims(&self, holder: Option<&str>, project: Option<&str>) -> Result<Vec<ClaimRow>, Error>;
150    /// Deadlines and scheduled dates inside `days`.
151    ///
152    /// # Errors
153    ///
154    /// Returns an error if the agenda cannot be listed.
155    fn agenda(&self, days: i64, project: Option<&str>) -> Result<Vec<AgendaRow>, Error>;
156    /// Parent and child tree rooted at `id`.
157    ///
158    /// # Errors
159    ///
160    /// Returns an error if the issue does not exist or the tree cannot be built.
161    fn tree(&self, id: &str) -> Result<TreeNode, Error>;
162    /// Related issues by graph walk and text overlap.
163    ///
164    /// # Errors
165    ///
166    /// Returns an error if the issue does not exist or related hits cannot be scored.
167    fn related(&self, id: &str, depth: usize, limit: usize) -> Result<Vec<RelatedHit>, Error>;
168    /// Project names under the layout prefix.
169    ///
170    /// # Errors
171    ///
172    /// Returns an error if the project list cannot be read.
173    fn projects(&self) -> Result<Vec<String>, Error>;
174    /// Claim `id` as [`Self::identity`]. `force` takes over another holder.
175    ///
176    /// # Errors
177    ///
178    /// Returns an error if the issue does not exist, is DONE or CANCELLED, is
179    /// held by another identity without `force`, or the write fails.
180    fn claim(&self, id: &str, force: bool) -> Result<MutResult, Error>;
181    /// Append a one-line logbook note.
182    ///
183    /// # Errors
184    ///
185    /// Returns an error if the issue does not exist, the text is empty, or the
186    /// write fails.
187    fn note(&self, id: &str, text: &str) -> Result<MutResult, Error>;
188    /// Change state, priority, or blocker edges.
189    ///
190    /// # Errors
191    ///
192    /// Returns an error if the issue does not exist, the change is refused, or
193    /// the write fails.
194    fn update(&self, req: UpdateReq) -> Result<MutResult, Error>;
195    /// Same metadata as [`Self::get`]; control also marks the issue opened.
196    ///
197    /// # Errors
198    ///
199    /// Returns an error if the issue does not exist or cannot be fetched.
200    fn open(&self, id: &str) -> Result<IssueDetail, Error>;
201
202    /// Core: wait on the file generation. Control: wait for `vault/changed`.
203    ///
204    /// # Errors
205    ///
206    /// Returns an error if the wait cannot be started or a newer catalog cannot
207    /// be re-read.
208    fn wait(&self, last: u64, timeout_ms: u64) -> Result<u64, Error>;
209
210    /// Last `since_revision` sent on list/ready. `None` means the field was
211    /// omitted. Default is "not recorded".
212    fn last_since_revision(&self) -> Option<Option<u64>> {
213        None
214    }
215
216    /// Drop `since_revision` on the next list/ready. Serve `unchanged` is
217    /// catalog-wide, so a pane or project change must fetch a full page.
218    fn invalidate_since(&self) {}
219
220    /// Re-read the files. Core uses this after an out-of-band write such as
221    /// `ops::create`. Control is a no-op; serve sees the file event.
222    ///
223    /// # Errors
224    ///
225    /// Returns an error if the catalog cannot be re-read. Control never fails.
226    fn refresh(&self) -> Result<(), Error> {
227        Ok(())
228    }
229}
230
231#[cfg(test)]
232mod tests {
233    use super::SinceGate;
234
235    #[test]
236    fn after_attach_first_list_omits_since_revision() {
237        let gate = SinceGate::after_attach();
238        assert_eq!(gate.next(7), None);
239        assert_eq!(gate.next(7), Some(7));
240        assert_eq!(gate.next(8), Some(8));
241    }
242
243    #[test]
244    fn a_zero_revision_never_sends_since() {
245        let gate = SinceGate::after_attach();
246        assert_eq!(gate.next(0), None);
247        assert_eq!(gate.next(0), None);
248    }
249
250    #[test]
251    fn invalidate_omits_the_next_since() {
252        let gate = SinceGate::after_attach();
253        assert_eq!(gate.next(7), None);
254        assert_eq!(gate.next(7), Some(7));
255        gate.invalidate();
256        assert_eq!(gate.next(7), None);
257        assert_eq!(gate.next(7), Some(7));
258    }
259}