loopflow 0.12.32

//! SQLite persistence for Project and Tasks.

use std::path::PathBuf;

// Product writes read before they write (for example, validating parent Work),
// so a deferred transaction has to upgrade its read lock to a write
// lock. Under WAL, SQLite fails that upgrade immediately rather than waiting —
// `busy_timeout` is never consulted, because waiting on an upgrade can deadlock
// two upgraders. Beginning IMMEDIATE takes the write lock up front, where
// `busy_timeout` does apply, so a second `lf` process queues instead of dying
// with `database is locked`.
use rusqlite::{params, Connection, OptionalExtension, ToSql, TransactionBehavior};
use time::OffsetDateTime;

use crate::child::AbandonIntent;
use crate::durable::Author;
use crate::id::WaveId;
use crate::planning::{LinearIssueId, LinearProjectId, ProjectPlan, TaskPlan};
use crate::store::rows::now_unix;
use crate::store::{StoreError, StoreResult};
use crate::work::project::{Project, ProjectEvent, ProjectEventKind, ProjectId};
use crate::work::task::{
    CiObservation, GithubObservation, GithubPr, LinearObservationApply, LinearObservationOutcome,
    PmWritebackState, PrMergeRequest, PrPhase, PrPresentation, PrPublication, Task, TaskEvent,
    TaskEventKind, TaskId, TaskLinearObservation, TaskPr, TaskPrId, TaskPrRepairKind,
};

use super::durable::{create_project_work, create_task_work};
use super::SqliteStore;

impl SqliteStore {
    pub(crate) fn task_checkouts(&self) -> StoreResult<Vec<super::TaskCheckout>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let mut statement = conn.prepare(
            "SELECT t.id, t.external_issue_id, t.issue_identifier, t.worktree, p.home_id
             FROM tasks t LEFT JOIN work_placements p ON p.task_id=t.id",
        )?;
        let rows = statement.query_map([], |row| {
            let home: Option<String> = row.get(4)?;
            Ok(super::TaskCheckout {
                task_id: TaskId::from_raw(row.get::<_, String>(0)?),
                issue_id: row.get(1)?,
                issue_identifier: row.get(2)?,
                worktree: PathBuf::from(row.get::<_, String>(3)?),
                home_id: home
                    .map(|id| crate::durable::HomeId::parse(&id))
                    .transpose()
                    .map_err(|error| invalid_column(4, error))?,
            })
        })?;
        rows.map(|row| row.map_err(StoreError::from)).collect()
    }

    // Durable Tasks: Linear identity, immutable placement, commands,
    // and lifecycle events share one sqlite transaction boundary.

    pub fn insert_task(&self, task: &Task, pr: &TaskPr) -> StoreResult<()> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        insert_initial_task(&transaction, task, pr)?;
        transaction.commit()?;
        Ok(())
    }

    pub fn insert_task_with_worktree(&self, task: &Task, pr: &TaskPr) -> StoreResult<()> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        insert_initial_task(&transaction, task, pr)?;
        insert_task_event_in(
            &transaction,
            &task.id,
            &TaskEventKind::WorktreeInitializing {
                pr_id: pr.id.clone(),
                sequence: pr.sequence,
                branch: pr.branch.clone(),
                path: task.worktree.display().to_string(),
                base_commit: pr.base_commit.clone(),
            },
        )?;
        transaction.commit()?;
        Ok(())
    }

    pub fn update_task_plan(&self, task_id: &TaskId, plan: &TaskPlan) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let changed = conn.execute(
            "UPDATE tasks SET issue_identifier=?2, issue_title=?3, issue_description=?4,
                 pm_snapshot_synced_at=?5 WHERE id=?1 AND external_issue_id=?6",
            params![
                task_id.as_str(),
                plan.identifier,
                plan.title,
                plan.description,
                plan.pm_snapshot_synced_at,
                plan.id.as_str()
            ],
        )?;
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        Ok(())
    }

    pub fn update_task_pm_writeback(
        &self,
        task_id: &TaskId,
        state: &PmWritebackState,
        updated_at: OffsetDateTime,
    ) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        update_task_pm_writeback_in(&conn, task_id, state, updated_at)
    }

    pub fn update_task(&self, task: &Task) -> StoreResult<()> {
        validate_task(task)?;
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        validate_task_project(&transaction, task)?;
        let parameters = task_params(task);
        let changed = transaction.execute(
            TASK_UPDATE,
            rusqlite::params_from_iter(parameters.iter().map(|value| value.as_ref())),
        )?;
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        transaction.commit()?;
        Ok(())
    }

    pub fn set_task_agent(&self, task_id: &TaskId, agent: &str) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let changed = conn.execute(
            "UPDATE tasks SET agent=?2, updated_at=?3 WHERE id=?1",
            params![task_id.as_str(), agent, now_unix()],
        )?;
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        Ok(())
    }

    pub(crate) fn restart_task_flow(
        &self,
        task: &Task,
        expected: Option<&crate::durable::FlowSession>,
        checkpoint_head: &str,
    ) -> StoreResult<()> {
        validate_task(task)?;
        if checkpoint_head.trim().is_empty() {
            return Err(StoreError::InvalidData(
                "Task restart requires a checkpoint head".to_string(),
            ));
        }
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        super::durable::require_ready_work(
            &transaction,
            &crate::durable::WorkRef::Task(task.id.clone()),
        )?;
        let current = super::flows::task_flow_in(&transaction, &task.id)?;
        if current.as_ref() != expected
            || current
                .as_ref()
                .is_some_and(|position| position.claim.is_some())
        {
            return Err(StoreError::InvalidAuthority(
                "Task execution changed before restart; stop the current worker before retrying"
                    .into(),
            ));
        }
        validate_task_project(&transaction, task)?;
        transaction.execute(
            &format!(
                "UPDATE flow_sessions SET state='replaced', ended_at=?2 WHERE {}",
                super::flows::TASK_INVOCATION
            ),
            params![task.id.as_str(), now_unix()],
        )?;
        transaction.execute(
            "UPDATE tasks SET current_invocation_id=NULL WHERE id=?1",
            [task.id.as_str()],
        )?;
        let parameters = task_params(task);
        transaction.execute(
            TASK_UPDATE,
            rusqlite::params_from_iter(parameters.iter().map(|value| value.as_ref())),
        )?;
        insert_task_event_in(
            &transaction,
            &task.id,
            &TaskEventKind::Progress {
                summary: format!("Task restarted from checkpoint {checkpoint_head}"),
            },
        )?;
        transaction.commit()?;
        Ok(())
    }

    pub fn rebind_task_issue_identifier(
        &self,
        issue_id: &str,
        old_identifier: &str,
        new_identifier: &str,
    ) -> StoreResult<bool> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let tx = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let Some((task_id, current_identifier)) = tx
            .query_row(
                "SELECT id, issue_identifier FROM tasks WHERE external_issue_id=?1",
                [issue_id],
                |row| Ok((row.get::<_, String>(0)?, row.get::<_, String>(1)?)),
            )
            .optional()?
        else {
            return Ok(false);
        };
        if current_identifier == new_identifier {
            return Ok(false);
        }
        if current_identifier != old_identifier {
            return Err(StoreError::InvalidData(format!(
                "Task {task_id} identifies issue {issue_id} as {current_identifier}, not {old_identifier}"
            )));
        }
        let changed = tx.execute(
            "UPDATE tasks SET issue_identifier=?3 WHERE id=?1 AND issue_identifier=?2",
            params![task_id, old_identifier, new_identifier],
        )?;
        if changed == 0 {
            return Err(StoreError::InvalidData(format!(
                "Task {task_id} changed during its team migration"
            )));
        }
        tx.execute(
            "UPDATE tasks SET updated_at=?2 WHERE id=?1",
            params![task_id, now_unix()],
        )?;
        tx.commit()?;
        Ok(true)
    }

    pub fn complete_task(&self, task: &Task, skipped_pr: Option<&TaskPr>) -> StoreResult<()> {
        validate_task(task)?;
        if let Some(pr) = skipped_pr {
            validate_task_pr(pr)?;
            if pr.task_id != task.id || pr.phase() != PrPhase::Working {
                return Err(StoreError::InvalidData(
                    "empty completion requires an unpublished Working Task PR".to_string(),
                ));
            }
        }
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        validate_task_project(&transaction, task)?;
        if let Some(pr) = skipped_pr {
            if transaction.execute(
                "UPDATE task_prs SET abandoned_at=?3, updated_at=?3
                 WHERE id=?1 AND task_id=?2
                   AND publication_requested_at IS NULL
                   AND merge_commit IS NULL AND abandoned_at IS NULL",
                params![pr.id.as_str(), pr.task_id.as_str(), now_unix()],
            )? == 0
            {
                return Err(StoreError::NotFound);
            }
        }
        update_task_pm_writeback_in(&transaction, &task.id, &task.pm_writeback, task.updated_at)?;
        complete_task_work_in(&transaction, task)?;
        // Cleanup settles the selected Flow after both driver and step exit.
        transaction.commit()?;
        Ok(())
    }

    pub fn task(&self, task_id: &TaskId) -> StoreResult<Option<Task>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        task_on(&conn, task_id)
    }

    pub fn task_by_issue(&self, issue: &str) -> StoreResult<Option<Task>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let query = format!(
            "{TASK_COLUMNS} WHERE t.id=?1 OR t.external_issue_id=?1 OR t.issue_identifier=?1"
        );
        let mut statement = conn.prepare(&query)?;
        let rows = statement.query_map(params![issue], map_task_row)?;
        let mut tasks = Vec::new();
        for row in rows {
            tasks.push(row?);
        }
        resolve_current_task(issue, tasks)
    }

    pub fn task_by_branch(&self, branch: &str) -> StoreResult<Option<Task>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let query = format!(
            "{TASK_COLUMNS} WHERE EXISTS (
                SELECT 1 FROM task_prs matched
                WHERE matched.task_id=t.id AND matched.branch=?1
                  AND matched.abandoned_at IS NULL
                  AND (
                    matched.merge_commit IS NULL
                    OR NOT EXISTS (
                        SELECT 1 FROM task_prs active
                        WHERE active.task_id=t.id
                          AND active.merge_commit IS NULL
                          AND active.abandoned_at IS NULL
                    )
                  )
            )"
        );
        let mut statement = conn.prepare(&query)?;
        let rows = statement.query_map(params![branch], map_task_row)?;
        let mut tasks = Vec::new();
        for row in rows {
            tasks.push(row?);
        }
        resolve_current_task(branch, tasks)
    }

    pub fn list_tasks(&self, wave_id: Option<&WaveId>) -> StoreResult<Vec<Task>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let (query, parameter): (String, Option<&dyn ToSql>) = match wave_id {
            Some(wave_id) => (
                format!("{TASK_COLUMNS} WHERE p.wave_id=?1 AND {TASK_VISIBLE} ORDER BY t.updated_at DESC"),
                Some(wave_id as &dyn ToSql),
            ),
            None => (format!("{TASK_COLUMNS} WHERE {TASK_VISIBLE} ORDER BY t.updated_at DESC"), None),
        };
        let mut statement = conn.prepare(&query)?;
        let mut tasks = Vec::new();
        if let Some(parameter) = parameter {
            let rows = statement.query_map([parameter], map_task_row)?;
            for row in rows {
                tasks.push(row?);
            }
        } else {
            let rows = statement.query_map([], map_task_row)?;
            for row in rows {
                tasks.push(row?);
            }
        }
        Ok(tasks)
    }

    /// Select a dependency without claiming that Git or GitHub has moved.
    pub fn stack_task_pr(&self, expected: &TaskPr, parent_id: &TaskPrId) -> StoreResult<()> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let tx = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let child = active_task_pr_on(&tx, &expected.task_id)?.ok_or(StoreError::NotFound)?;
        if child.id != expected.id || child.base_commit != expected.base_commit {
            return Err(StoreError::InvalidAuthority(
                "Task PR changed; retry preparation".into(),
            ));
        }
        if child.parent_pr_id.as_ref() == Some(parent_id) {
            return Ok(());
        }
        if child.parent_pr_id.is_some() {
            return Err(StoreError::InvalidAuthority(
                "Task PR already has a parent; retain its dependency until explicit reparenting"
                    .into(),
            ));
        }
        if child
            .publication
            .as_ref()
            .is_some_and(|publication| publication.merge.is_some())
        {
            return Err(StoreError::InvalidAuthority(
                "Task PR has a merge request; cancel its delivery before selecting a parent".into(),
            ));
        }
        let ready: bool = tx.query_row(
            "SELECT work_state='ready' FROM tasks WHERE id=?1",
            [child.task_id.as_str()],
            |row| row.get(0),
        )?;
        let claimed: bool = tx.query_row(
            "SELECT EXISTS(SELECT 1 FROM flow_sessions WHERE task_id=?1 AND claim_json IS NOT NULL)",
            [child.task_id.as_str()], |row| row.get(0),
        )?;
        if !ready || claimed {
            return Err(StoreError::InvalidAuthority(
                "Task must be ready with its worker claim released before selecting a parent; use the existing Task stop/recovery path".into(),
            ));
        }
        let parent = task_pr_on(&tx, parent_id)?.ok_or(StoreError::NotFound)?;
        if parent.is_settled() || parent.github().is_none() {
            return Err(StoreError::InvalidAuthority(
                "open the parent PR before stacking work on it".into(),
            ));
        }
        let same_repo: bool = tx.query_row(
            "SELECT cw.repo=pw.repo FROM tasks c
             JOIN projects cp ON cp.id=c.project_id JOIN waves cw ON cw.id=cp.wave_id
             JOIN tasks p ON p.id=?2
             JOIN projects pp ON pp.id=p.project_id JOIN waves pw ON pw.id=pp.wave_id
             WHERE c.id=?1",
            params![child.task_id.as_str(), parent.task_id.as_str()],
            |row| row.get(0),
        )?;
        if !same_repo {
            return Err(StoreError::InvalidAuthority(
                "stack parent belongs to another repository".into(),
            ));
        }
        let mut ancestor = Some(parent);
        let mut seen = std::collections::HashSet::new();
        while let Some(pr) = ancestor {
            if pr.task_id == child.task_id || !seen.insert(pr.id.clone()) {
                return Err(StoreError::InvalidAuthority(
                    "stack parent would create a dependency cycle".into(),
                ));
            }
            ancestor = match pr.parent_pr_id {
                Some(id) => Some(task_pr_on(&tx, &id)?.ok_or(StoreError::NotFound)?),
                None => None,
            };
        }
        tx.execute(
            "UPDATE task_prs SET parent_pr_id=?2, updated_at=?3 WHERE id=?1",
            params![child.id.as_str(), parent_id.as_str(), now_unix()],
        )?;
        tx.commit()?;
        Ok(())
    }

    pub fn update_task_pr(&self, pr: &TaskPr) -> StoreResult<()> {
        validate_task_pr(pr)?;
        let conn = self.conn.lock().expect("store mutex poisoned");
        let changed = update_task_pr(&conn, pr)?;
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        Ok(())
    }

    pub(crate) fn record_task_pr_repair_incident(
        &self,
        pr_id: &TaskPrId,
        kind: TaskPrRepairKind,
        occurred_at: OffsetDateTime,
    ) -> StoreResult<bool> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        record_task_pr_repair_incident_on(&conn, pr_id, kind, occurred_at)
    }

    pub fn heal_task_pr_base(&self, pr: &TaskPr) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        if heal_task_pr_base(&conn, pr)? == 0 {
            return Err(StoreError::NotFound);
        }
        Ok(())
    }

    pub fn task_prs(&self, task_id: &TaskId) -> StoreResult<Vec<TaskPr>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let mut statement = conn.prepare(&format!(
            "{TASK_PR_COLUMNS} WHERE task_id=?1 ORDER BY sequence"
        ))?;
        let rows = statement.query_map(params![task_id.as_str()], map_task_pr_row)?;
        Ok(rows.collect::<Result<Vec<_>, _>>()?)
    }

    pub fn task_pr(&self, pr_id: &TaskPrId) -> StoreResult<Option<TaskPr>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        task_pr_on(&conn, pr_id)
    }

    pub fn active_task_pr(&self, task_id: &TaskId) -> StoreResult<Option<TaskPr>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        active_task_pr_on(&conn, task_id)
    }

    pub fn settle_task_pr(&self, settled: &TaskPr, next: Option<&TaskPr>) -> StoreResult<()> {
        validate_task_pr_settlement(settled, next)?;
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        settle_task_pr_in(&transaction, settled, next)?;
        transaction.commit()?;
        Ok(())
    }

    /// Move a stacked Task PR to its parent's current tip, or clear the parent
    /// after that work reaches the default branch. This deliberately moves the
    /// otherwise-immutable `base_commit` through a dedicated transition.
    pub fn sync_task_pr(
        &self,
        pr_id: &TaskPrId,
        new_base: &str,
        clear_parent: bool,
        updated_at: OffsetDateTime,
    ) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let changed = if clear_parent {
            conn.execute(
                "UPDATE task_prs SET base_commit=?2, parent_pr_id=NULL, updated_at=?3 WHERE id=?1",
                params![pr_id.as_str(), new_base, updated_at.unix_timestamp()],
            )?
        } else {
            conn.execute(
                "UPDATE task_prs SET base_commit=?2, updated_at=?3 WHERE id=?1 AND parent_pr_id IS NOT NULL",
                params![pr_id.as_str(), new_base, updated_at.unix_timestamp()],
            )?
        };
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        Ok(())
    }

    pub(crate) fn settle_task_pr_merged(
        &self,
        settled: &TaskPr,
        merged_at: Option<OffsetDateTime>,
    ) -> StoreResult<crate::store::TaskPrMergeEvidenceOutcome> {
        validate_task_pr_settlement(settled, None)?;
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let outcome = settle_task_pr_merged_in(&transaction, settled, merged_at)?;
        transaction.commit()?;
        Ok(outcome)
    }

    pub fn task_linear_observation(
        &self,
        task_id: &TaskId,
    ) -> StoreResult<Option<TaskLinearObservation>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.query_row(
            "SELECT task_id, last_revision, last_title, last_description,
                    last_success_at, degraded_reason, updated_at
             FROM task_linear_observations WHERE task_id=?1",
            params![task_id.as_str()],
            map_task_linear_observation_row,
        )
        .optional()
        .map_err(StoreError::from)
    }

    /// Persist one Linear observation as Task direction, atomically. Exactly-once
    /// comments are imported on the first read and deduplicated by revision.
    /// Issue revisions guard definition changes independently of comments.
    pub fn apply_linear_observation(
        &self,
        apply: &LinearObservationApply,
    ) -> StoreResult<LinearObservationOutcome> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;

        let existing = transaction
            .query_row(
                "SELECT last_revision, last_title, last_description
                 FROM task_linear_observations WHERE task_id=?1",
                params![apply.task_id.as_str()],
                |row| {
                    Ok((
                        row.get::<_, String>(0)?,
                        row.get::<_, String>(1)?,
                        row.get::<_, String>(2)?,
                    ))
                },
            )
            .optional()?;

        let observed_at = apply.observed_at.unix_timestamp();
        let mut follow_ups_created = Vec::new();
        for follow_up in &apply.follow_ups {
            if let Some(id) = ingest_linear_comment(
                &transaction,
                apply.task_id.as_str(),
                &follow_up.comment_id,
                &follow_up.text,
                observed_at,
            )? {
                follow_ups_created.push(id);
            }
        }

        let Some((last_revision, last_title, last_description)) = existing else {
            // Baseline the definition; existing comments were imported above.
            transaction.execute(
                "INSERT INTO task_linear_observations (
                    task_id, last_revision, last_title, last_description,
                    last_success_at, degraded_reason, updated_at
                 ) VALUES (?1, ?2, ?3, ?4, ?5, NULL, ?5)",
                params![
                    apply.task_id.as_str(),
                    apply.revision,
                    apply.title,
                    apply.description,
                    observed_at,
                ],
            )?;
            transaction.commit()?;
            return Ok(LinearObservationOutcome {
                baselined: true,
                content_steer_applied: false,
                follow_ups_created,
            });
        };

        // Monotonic guard: an out-of-order response older than what we have
        // carries stale content, so drop it rather than let it revert direction.
        if apply.revision.as_str() < last_revision.as_str() {
            transaction.commit()?;
            return Ok(LinearObservationOutcome {
                baselined: false,
                content_steer_applied: false,
                follow_ups_created,
            });
        }

        let mut content_steer_applied = false;
        if let Some(text) = &apply.content_steer {
            if last_title != apply.title || last_description != apply.description {
                Self::append_task_steer_in(&transaction, &apply.task_id, &Author::User, text)?;
                content_steer_applied = true;
            }
        }

        transaction.execute(
            "UPDATE task_linear_observations
             SET last_revision=?2, last_title=?3, last_description=?4,
                 last_success_at=?5, degraded_reason=NULL, updated_at=?5
             WHERE task_id=?1",
            params![
                apply.task_id.as_str(),
                apply.revision,
                apply.title,
                apply.description,
                observed_at,
            ],
        )?;
        transaction.commit()?;
        Ok(LinearObservationOutcome {
            baselined: false,
            content_steer_applied,
            follow_ups_created,
        })
    }

    /// Persist one participant-authored Linear comment as a FIFO Task Steer, exactly once.
    /// Webhook comments arrive one at a time (unlike the snapshot edit path), and
    /// Linear delivers at-least-once — so the `task_linear_ingested_comments`
    /// ledger is the guard: the Steer is created only on the comment id's first
    /// insertion. Returns the created Steer id, or `None` for a
    /// duplicate delivery.
    pub fn apply_linear_comment(
        &self,
        task_id: &TaskId,
        comment_id: &str,
        text: &str,
        observed_at: OffsetDateTime,
    ) -> StoreResult<Option<i64>> {
        let observed_at = observed_at.unix_timestamp();
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let created = ingest_linear_comment(
            &transaction,
            task_id.as_str(),
            comment_id,
            text,
            observed_at,
        )?;
        if created.is_some() {
            // Best-effort freshness for status; a Task missing its seed row
            // (legacy) simply has nothing to update.
            transaction.execute(
                "UPDATE task_linear_observations
                 SET last_success_at=?2, degraded_reason=NULL, updated_at=?2
                 WHERE task_id=?1",
                params![task_id.as_str(), observed_at],
            )?;
        }
        transaction.commit()?;
        Ok(created)
    }

    /// Record that the latest observation failed, without moving the cursor. A
    /// Task with no baseline yet has no row to mark, which is fine — status
    /// then simply shows no observation.
    pub fn mark_task_linear_degraded(&self, task_id: &TaskId, reason: &str) -> StoreResult<()> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.execute(
            "UPDATE task_linear_observations SET degraded_reason=?2, updated_at=?3
             WHERE task_id=?1",
            params![task_id.as_str(), reason, now_unix()],
        )?;
        Ok(())
    }

    pub fn append_task_event(
        &self,
        task_id: &TaskId,
        kind: &TaskEventKind,
    ) -> StoreResult<TaskEvent> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let event = insert_task_event_in(&transaction, task_id, kind)?;
        transaction.commit()?;
        Ok(event)
    }

    pub fn task_events_after(&self, task_id: &TaskId, cursor: i64) -> StoreResult<Vec<TaskEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        task_events_after_in(&conn, task_id, cursor)
    }

    pub fn task_event(&self, task_id: &TaskId, event_id: i64) -> StoreResult<Option<TaskEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.query_row(
            "SELECT id, task_id, kind_json, created_at
             FROM task_events WHERE task_id = ?1 AND id = ?2",
            params![task_id.as_str(), event_id],
            map_task_event_row,
        )
        .optional()
        .map_err(StoreError::from)
    }

    /// When this Task last appended a durable event. This is the progress
    /// signal the body observation reads: a live body that has written nothing to
    /// its event log past the stall deadline is stalled, not working. `None` means
    /// no events yet (the status change is the only progress the caller can use).
    pub fn latest_task_event_at(&self, task_id: &TaskId) -> StoreResult<Option<OffsetDateTime>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let seconds: Option<i64> = conn.query_row(
            "SELECT MAX(created_at) FROM task_events WHERE task_id = ?1",
            params![task_id.as_str()],
            |row| row.get(0),
        )?;
        Ok(seconds.map(crate::store::rows::unix_to_datetime))
    }

    /// The newest `limit` events, newest first. Recovery reads a bounded window
    /// rather than the whole log: a long-lived Task accumulates thousands of
    /// events, and the attempt count only ever looks at the recent tail.
    pub fn recent_task_events(&self, task_id: &TaskId, limit: u32) -> StoreResult<Vec<TaskEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let mut statement = conn.prepare(
            "SELECT id, task_id, kind_json, created_at
             FROM task_events WHERE task_id = ?1 ORDER BY id DESC LIMIT ?2",
        )?;
        let rows = statement.query_map(params![task_id.as_str(), limit], map_task_event_row)?;
        let mut events = Vec::new();
        for row in rows {
            events.push(row?);
        }
        Ok(events)
    }

    pub fn latest_task_event(&self, task_id: &TaskId) -> StoreResult<Option<TaskEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.query_row(
            "SELECT id, task_id, kind_json, created_at
             FROM task_events WHERE task_id = ?1 ORDER BY id DESC LIMIT 1",
            params![task_id.as_str()],
            map_task_event_row,
        )
        .optional()
        .map_err(StoreError::from)
    }

    // Projects are durable KR-pursuit children. They share the same
    // process/receipt shape as Tasks but deliberately own no worktree.

    pub fn insert_project(&self, project: &Project) -> StoreResult<()> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        transaction.execute(
            PROJECT_INSERT,
            rusqlite::params_from_iter(project_params(project).iter().map(|value| value.as_ref())),
        )?;
        create_project_work(&transaction, project)?;
        transaction.commit()?;
        Ok(())
    }

    pub fn update_project(&self, project: &Project) -> StoreResult<()> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let parameters = project_fact_params(project);
        let changed = transaction.execute(
            PROJECT_FACT_UPDATE,
            rusqlite::params_from_iter(parameters.iter().map(|value| value.as_ref())),
        )?;
        if changed == 0 {
            return Err(StoreError::NotFound);
        }
        transaction.commit()?;
        Ok(())
    }

    pub fn project(&self, project_id: &ProjectId) -> StoreResult<Option<Project>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.query_row(
            PROJECT_SELECT,
            params![project_id.as_str()],
            map_project_row,
        )
        .optional()
        .map_err(StoreError::from)
    }

    pub fn project_by_project(&self, project: &str) -> StoreResult<Option<Project>> {
        if let Ok(project_id) = ProjectId::parse(project) {
            return self.project(&project_id);
        }
        let conn = self.conn.lock().expect("store mutex poisoned");
        let query = format!(
            "{PROJECT_COLUMNS}
             WHERE external_project_id=?1 OR project_slug=?1
             ORDER BY created_at DESC, id DESC
             LIMIT 1"
        );
        conn.query_row(&query, params![project], map_project_row)
            .optional()
            .map_err(StoreError::from)
    }

    pub fn list_projects(&self, wave_id: Option<&WaveId>) -> StoreResult<Vec<Project>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let query = match wave_id {
            Some(_) => {
                format!("{PROJECT_COLUMNS} WHERE wave_id=?1 ORDER BY updated_at DESC")
            }
            None => format!("{PROJECT_COLUMNS} ORDER BY updated_at DESC"),
        };
        let mut statement = conn.prepare(&query)?;
        let mut projects = Vec::new();
        if let Some(wave_id) = wave_id {
            let rows = statement.query_map(params![wave_id], map_project_row)?;
            for row in rows {
                projects.push(row?);
            }
        } else {
            let rows = statement.query_map([], map_project_row)?;
            for row in rows {
                projects.push(row?);
            }
        }
        Ok(projects)
    }

    pub fn append_project_event(
        &self,
        project_id: &ProjectId,
        kind: &ProjectEventKind,
    ) -> StoreResult<ProjectEvent> {
        let mut conn = self.conn.lock().expect("store mutex poisoned");
        let transaction = conn.transaction_with_behavior(TransactionBehavior::Immediate)?;
        let project = transaction.query_row(
            PROJECT_SELECT,
            params![project_id.as_str()],
            map_project_row,
        )?;
        let event = insert_project_event_in(&transaction, &project, kind)?;
        transaction.commit()?;
        Ok(event)
    }

    pub fn project_events_after(
        &self,
        project_id: &ProjectId,
        cursor: i64,
    ) -> StoreResult<Vec<ProjectEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let mut statement = conn.prepare(
            "SELECT id, project_id, kind_json, created_at
             FROM project_events WHERE project_id=?1 AND id>?2 ORDER BY id",
        )?;
        let rows =
            statement.query_map(params![project_id.as_str(), cursor], map_project_event_row)?;
        let mut events = Vec::new();
        for row in rows {
            events.push(row?);
        }
        Ok(events)
    }

    /// When this Project last appended a durable event. The progress
    /// signal for the Project body observation, mirroring [`Self::latest_task_event_at`].
    pub fn latest_project_event_at(
        &self,
        project_id: &ProjectId,
    ) -> StoreResult<Option<OffsetDateTime>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let seconds: Option<i64> = conn.query_row(
            "SELECT MAX(created_at) FROM project_events WHERE project_id = ?1",
            params![project_id.as_str()],
            |row| row.get(0),
        )?;
        Ok(seconds.map(crate::store::rows::unix_to_datetime))
    }

    pub fn latest_project_event(
        &self,
        project_id: &ProjectId,
    ) -> StoreResult<Option<ProjectEvent>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        conn.query_row(
            "SELECT id, project_id, kind_json, created_at
             FROM project_events WHERE project_id=?1 ORDER BY id DESC LIMIT 1",
            params![project_id.as_str()],
            map_project_event_row,
        )
        .optional()
        .map_err(StoreError::from)
    }

    pub fn latest_project_failure(
        &self,
        project_id: &ProjectId,
    ) -> StoreResult<Option<crate::work::project::HistoricalFailure>> {
        let conn = self.conn.lock().expect("store mutex poisoned");
        let event = conn
            .query_row(
                "SELECT id, project_id, kind_json, created_at
                 FROM project_events
                 WHERE project_id=?1 AND json_extract(kind_json, '$.kind')='failed'
                 ORDER BY id DESC LIMIT 1",
                params![project_id.as_str()],
                map_project_event_row,
            )
            .optional()?;
        Ok(event
            .as_ref()
            .and_then(crate::work::project::HistoricalFailure::from_event))
    }
}

fn validate_task(task: &Task) -> StoreResult<()> {
    task.validate()
        .map_err(|error| StoreError::InvalidData(error.to_string()))
}

fn update_task_pm_writeback_in(
    conn: &Connection,
    task_id: &TaskId,
    state: &PmWritebackState,
    updated_at: OffsetDateTime,
) -> StoreResult<()> {
    let changed = conn.execute(
        "UPDATE tasks SET pm_writeback_json=?2, updated_at=?3 WHERE id=?1",
        params![
            task_id.as_str(),
            serde_json::to_string(state).expect("Task PM writeback state must serialize"),
            updated_at.unix_timestamp(),
        ],
    )?;
    if changed == 0 {
        return Err(StoreError::NotFound);
    }
    Ok(())
}

fn complete_task_work_in(conn: &Connection, task: &Task) -> StoreResult<()> {
    let state: String = conn.query_row(
        "SELECT work_state FROM tasks WHERE id=?1",
        [task.id.as_str()],
        |row| row.get(0),
    )?;
    match state.as_str() {
        "done" => return Ok(()),
        "ready" => {}
        "abandoned" => {
            return Err(StoreError::InvalidData(format!(
                "Task {} Work is abandoned and cannot be completed",
                task.id
            )))
        }
        other => {
            return Err(StoreError::InvalidData(format!(
                "Task {} Work has invalid state {other:?}",
                task.id
            )))
        }
    }
    if conn.execute(
        "UPDATE tasks SET work_state='done', work_terminal_at=?2
         WHERE id=?1 AND work_state='ready'",
        params![task.id.as_str(), now_unix()],
    )? != 1
    {
        return Err(StoreError::InvalidData(format!(
            "Task {} Work changed while completion was being recorded",
            task.id
        )));
    }
    insert_task_event_in(
        conn,
        &task.id,
        &TaskEventKind::Completed {
            summary: "Task completed".to_string(),
        },
    )?;
    Ok(())
}

fn resolve_current_task(key: &str, mut tasks: Vec<Task>) -> StoreResult<Option<Task>> {
    if tasks.len() > 1 {
        return Err(StoreError::InvalidData(format!(
            "multiple stable Tasks resolve to {key:?}"
        )));
    }
    Ok(tasks.pop())
}

fn validate_task_pr(pr: &TaskPr) -> StoreResult<()> {
    pr.validate()
        .map_err(|error| StoreError::InvalidData(error.to_string()))
}

fn validate_initial_task_pr(task: &Task, pr: &TaskPr) -> StoreResult<()> {
    validate_task_pr(pr)?;
    if pr.task_id != task.id || pr.sequence != 1 || !pr.is_active() {
        return Err(StoreError::InvalidData(
            "Task requires its sequence-1 active PR".to_string(),
        ));
    }
    Ok(())
}

fn require_task_not_deleted(conn: &Connection, task: &Task) -> StoreResult<()> {
    let deleted: bool = conn.query_row(
        "SELECT EXISTS(SELECT 1 FROM task_deletions WHERE wave_id=?1 AND issue_id=?2)",
        params![task.wave_id.as_str(), task.plan.id.as_str()],
        |row| row.get(0),
    )?;
    if deleted {
        return Err(StoreError::InvalidAuthority(format!(
            "Task {} was deleted; create a new Task",
            task.plan.identifier
        )));
    }
    Ok(())
}

fn insert_initial_task(
    conn: &rusqlite::Transaction<'_>,
    task: &Task,
    pr: &TaskPr,
) -> StoreResult<()> {
    validate_task(task)?;
    validate_initial_task_pr(task, pr)?;
    validate_task_project(conn, task)?;
    require_task_not_deleted(conn, task)?;
    let expired: bool = conn.query_row(
        "SELECT EXISTS(SELECT 1 FROM projects p WHERE p.id=?1 AND
         (p.status != 'started' OR (SELECT count(*) FROM projects current
          WHERE current.wave_id=p.wave_id AND current.status='started') != 1))",
        [task.project_id.as_str()],
        |row| row.get(0),
    )?;
    if expired {
        return Err(StoreError::InvalidData(
            "cannot prepare a new Task in chapter history; refresh the Wave".into(),
        ));
    }

    let mut parameters = task_params(task);
    parameters.push(Box::new(task.agent.clone()));
    conn.execute(
        TASK_INSERT,
        rusqlite::params_from_iter(parameters.iter().map(|value| value.as_ref())),
    )?;
    create_task_work(conn, task)?;
    insert_task_pr(conn, pr)?;
    seed_task_linear_observation(conn, task)
}

/// Seed the Linear observation cursor from the planning directive, in the Task's
/// creation transaction. Webhooks only fire for changes *after* subscription, so
/// there is no cursor to build lazily on a first poll — seeding here means the
/// first issue-edit webhook diffs against the directive title/description instead of
/// baselining (and swallowing) it. The revision seeds empty so any real Linear
/// `updatedAt` wins the monotonic guard.
fn seed_task_linear_observation(conn: &Connection, task: &Task) -> StoreResult<()> {
    conn.execute(
        "INSERT OR IGNORE INTO task_linear_observations (
            task_id, last_revision, last_title, last_description,
            last_success_at, degraded_reason, updated_at
         ) VALUES (?1, '', ?2, ?3, ?4, NULL, ?4)",
        params![
            task.id.as_str(),
            task.plan.title,
            task.plan.description,
            now_unix(),
        ],
    )?;
    Ok(())
}

fn validate_task_project(conn: &Connection, task: &Task) -> StoreResult<()> {
    let owner = conn
        .query_row(
            "SELECT wave_id FROM projects WHERE id=?1",
            params![task.project_id.as_str()],
            |row| row.get::<_, String>(0),
        )
        .optional()?;
    let Some(wave_id) = owner else {
        return Err(StoreError::InvalidData(format!(
            "Task {} requires Project {}",
            task.id, task.project_id
        )));
    };
    if wave_id != task.wave_id.as_str() {
        return Err(StoreError::InvalidData(format!(
            "Project {} does not belong to Task {}'s Wave {}",
            task.project_id, task.id, task.wave_id
        )));
    }
    Ok(())
}

const TASK_INSERT: &str = "INSERT INTO tasks (
    id, project_id, external_issue_id, issue_identifier, issue_title,
    issue_description, pm_snapshot_synced_at, pm_writeback_json,
    worktree, workspace_slug,
    abandon_requested_at, abandon_reason, created_at, updated_at, agent
) VALUES (
    ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15
)";
const TASK_VISIBLE: &str = "NOT EXISTS (
    SELECT 1 FROM task_deletions d WHERE d.wave_id=p.wave_id AND d.issue_id=t.external_issue_id
)";
const TASK_COLUMNS: &str = "SELECT
    t.id, t.external_issue_id, t.issue_identifier, t.issue_title, t.issue_description,
    p.wave_id, t.worktree, t.workspace_slug,
    t.created_at, t.updated_at, t.pm_snapshot_synced_at, t.pm_writeback_json,
    t.project_id, t.abandon_requested_at, t.abandon_reason, t.agent
    FROM tasks t JOIN projects p ON p.id=t.project_id";
const TASK_UPDATE: &str = "UPDATE tasks SET
    external_issue_id=?3, issue_identifier=?4,
    issue_title=?5, issue_description=?6, pm_snapshot_synced_at=?7,
    pm_writeback_json=?8, worktree=?9, workspace_slug=?10,
    abandon_requested_at=?11, abandon_reason=?12, created_at=?13, updated_at=?14
    WHERE id=?1";
const TASK_PR_COLUMNS: &str = "SELECT
    id, task_id, sequence, slug, branch, base_commit,
    publication_requested_at, after_merge, next_slug, github_number, github_url,
    merge_commit, abandoned_at, created_at, updated_at,
    github_head_sha, ci_observation, parent_pr_id, github_observation,
    linear_attachment_id, linear_comment_id, linear_link_error,
    merge_mode, merge_requested_at, merge_head_sha,
    pr_title, pr_body, pr_copy_head_sha
    FROM task_prs";
const TASK_PR_SELECT: &str = "SELECT
    id, task_id, sequence, slug, branch, base_commit,
    publication_requested_at, after_merge, next_slug, github_number, github_url,
    merge_commit, abandoned_at, created_at, updated_at,
    github_head_sha, ci_observation, parent_pr_id, github_observation,
    linear_attachment_id, linear_comment_id, linear_link_error,
    merge_mode, merge_requested_at, merge_head_sha,
    pr_title, pr_body, pr_copy_head_sha
    FROM task_prs WHERE id=?1";
/// Persist one Linear comment as a Steer exactly once. The insert
/// into `task_linear_ingested_comments` is the guard — the command is written
/// only when the comment id is new to the ledger, so a redelivered webhook or an
/// overlapping catch-up read cannot double-deliver. Shared by the snapshot apply
/// loop and the single-comment webhook path.
fn ingest_linear_comment(
    conn: &rusqlite::Transaction<'_>,
    task_id: &str,
    comment_id: &str,
    text: &str,
    observed_at: i64,
) -> StoreResult<Option<i64>> {
    if let Some((id, _)) = comment_id.split_once('@') {
        let prefix = format!("{id}@");
        let latest: Option<String> = conn.query_row(
            "SELECT MAX(comment_id) FROM task_linear_ingested_comments WHERE task_id=?1 AND substr(comment_id, 1, length(?2))=?2",
            params![task_id, prefix], |row| row.get(0),
        )?;
        if latest.as_deref().is_some_and(|latest| latest > comment_id) {
            return Ok(None);
        }
    }
    let inserted = conn.execute(
        "INSERT OR IGNORE INTO task_linear_ingested_comments
            (task_id, comment_id, ingested_at) VALUES (?1, ?2, ?3)",
        params![task_id, comment_id, observed_at],
    )?;
    if inserted == 1 {
        let steer = SqliteStore::append_task_steer_in(
            conn,
            &TaskId::from_raw(task_id),
            &Author::User,
            text,
        )?;
        Ok(Some(steer.id))
    } else {
        Ok(None)
    }
}

fn task_params(task: &Task) -> Vec<Box<dyn ToSql>> {
    vec![
        Box::new(task.id.as_str().to_string()),
        Box::new(task.project_id.as_str().to_string()),
        Box::new(task.plan.id.as_str().to_string()),
        Box::new(task.plan.identifier.clone()),
        Box::new(task.plan.title.clone()),
        Box::new(task.plan.description.clone()),
        Box::new(task.plan.pm_snapshot_synced_at),
        Box::new(
            serde_json::to_string(&task.pm_writeback)
                .expect("Task PM writeback state must serialize"),
        ),
        Box::new(task.worktree.display().to_string()),
        Box::new(task.workspace_slug.clone()),
        Box::new(
            task.abandon_intent
                .as_ref()
                .map(|intent| intent.requested_at.unix_timestamp()),
        ),
        Box::new(
            task.abandon_intent
                .as_ref()
                .map(|intent| intent.reason.clone()),
        ),
        Box::new(task.created_at.unix_timestamp()),
        Box::new(task.updated_at.unix_timestamp()),
    ]
}

fn insert_task_pr(conn: &Connection, pr: &TaskPr) -> StoreResult<()> {
    validate_task_pr(pr)?;
    let publication = pr.publication.as_ref();
    let presentation = publication.and_then(|publication| publication.presentation.as_ref());
    let github = publication.and_then(|publication| publication.github.as_ref());
    let merge = publication.and_then(|publication| publication.merge.as_ref());
    conn.execute(
        "INSERT INTO task_prs (
            id, task_id, sequence, slug, branch, base_commit,
            publication_requested_at, after_merge, next_slug,
            github_number, github_url, merge_commit, abandoned_at,
            created_at, updated_at, github_head_sha, ci_observation, parent_pr_id,
            github_observation,
            linear_attachment_id, linear_comment_id, linear_link_error,
            merge_mode, merge_requested_at, merge_head_sha,
            pr_title, pr_body, pr_copy_head_sha
         ) VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15, ?16, ?17, ?18, ?19, ?20, ?21, ?22, ?23, ?24, ?25, ?26, ?27, ?28)",
        params![
            pr.id.as_str(),
            pr.task_id.as_str(),
            i64::from(pr.sequence),
            pr.slug,
            pr.branch,
            pr.base_commit,
            publication.map(|publication| publication.requested_at.unix_timestamp()),
            merge.map(|request| request.after_merge.as_str()),
            merge.and_then(|request| request.next_slug.as_deref()),
            github.map(|github| i64::from(github.number)),
            github.map(|github| github.url.as_str()),
            pr.merge_commit,
            pr.abandoned_at.map(OffsetDateTime::unix_timestamp),
            pr.created_at.unix_timestamp(),
            pr.updated_at.unix_timestamp(),
            github.and_then(|github| github.head_sha.as_deref()),
            task_pr_ci_json(pr)?,
            pr.parent_pr_id.as_ref().map(TaskPrId::as_str),
            task_pr_github_observation_json(pr)?,
            pr.linear_attachment_id.as_deref(),
            pr.linear_comment_id.as_deref(),
            pr.linear_link_error.as_deref(),
            merge.map(|request| request.mode.as_str()),
            merge.map(|request| request.requested_at.unix_timestamp()),
            merge.map(|request| request.head_sha.as_str()),
            presentation.map(|copy| copy.title.as_str()),
            presentation.map(|copy| copy.body.as_str()),
            presentation.map(|copy| copy.head_sha.as_str()),
        ],
    )?;
    Ok(())
}

fn record_task_pr_repair_incident_on(
    conn: &Connection,
    pr_id: &TaskPrId,
    kind: TaskPrRepairKind,
    occurred_at: OffsetDateTime,
) -> StoreResult<bool> {
    Ok(conn.execute(
        "INSERT INTO task_pr_repair_incidents (task_pr_id, kind, occurred_at)
         VALUES (?1, ?2, ?3)
         ON CONFLICT(task_pr_id, kind) DO NOTHING",
        params![pr_id.as_str(), kind.as_str(), occurred_at.unix_timestamp()],
    )? == 1)
}

fn update_task_pr(conn: &Connection, pr: &TaskPr) -> StoreResult<usize> {
    validate_task_pr(pr)?;
    let publication = pr.publication.as_ref();
    let presentation = publication.and_then(|publication| publication.presentation.as_ref());
    let github = publication.and_then(|publication| publication.github.as_ref());
    let merge = publication.and_then(|publication| publication.merge.as_ref());
    conn.execute(
        "UPDATE task_prs SET
            publication_requested_at=?7, after_merge=?8, next_slug=?9,
            github_number=?10, github_url=?11, merge_commit=?12,
            abandoned_at=?13, updated_at=?15, github_head_sha=?16,
            ci_observation=?17, github_observation=?19,
            linear_attachment_id=?20, linear_comment_id=?21, linear_link_error=?22,
            merge_mode=?23, merge_requested_at=?24, merge_head_sha=?25,
            pr_title=?26, pr_body=?27, pr_copy_head_sha=?28
         WHERE id=?1 AND task_id=?2 AND sequence=?3 AND slug=?4
           AND branch=?5 AND base_commit=?6 AND created_at=?14",
        params![
            pr.id.as_str(),
            pr.task_id.as_str(),
            i64::from(pr.sequence),
            pr.slug,
            pr.branch,
            pr.base_commit,
            publication.map(|publication| publication.requested_at.unix_timestamp()),
            merge.map(|request| request.after_merge.as_str()),
            merge.and_then(|request| request.next_slug.as_deref()),
            github.map(|github| i64::from(github.number)),
            github.map(|github| github.url.as_str()),
            pr.merge_commit,
            pr.abandoned_at.map(OffsetDateTime::unix_timestamp),
            pr.created_at.unix_timestamp(),
            pr.updated_at.unix_timestamp(),
            github.and_then(|github| github.head_sha.as_deref()),
            task_pr_ci_json(pr)?,
            pr.parent_pr_id.as_ref().map(TaskPrId::as_str),
            task_pr_github_observation_json(pr)?,
            pr.linear_attachment_id.as_deref(),
            pr.linear_comment_id.as_deref(),
            pr.linear_link_error.as_deref(),
            merge.map(|request| request.mode.as_str()),
            merge.map(|request| request.requested_at.unix_timestamp()),
            merge.map(|request| request.head_sha.as_str()),
            presentation.map(|copy| copy.title.as_str()),
            presentation.map(|copy| copy.body.as_str()),
            presentation.map(|copy| copy.head_sha.as_str()),
        ],
    )
    .map_err(StoreError::from)
}

/// Move a Task PR's `base_commit` range anchor forward. `base_commit` is part of
/// `update_task_pr`'s optimistic identity, so healing it needs a dedicated write
/// keyed on the row's true identity (id + task + sequence).
fn heal_task_pr_base(conn: &Connection, pr: &TaskPr) -> StoreResult<usize> {
    validate_task_pr(pr)?;
    conn.execute(
        "UPDATE task_prs SET base_commit=?4, updated_at=?5
         WHERE id=?1 AND task_id=?2 AND sequence=?3",
        params![
            pr.id.as_str(),
            pr.task_id.as_str(),
            i64::from(pr.sequence),
            pr.base_commit,
            pr.updated_at.unix_timestamp(),
        ],
    )
    .map_err(StoreError::from)
}

/// Serialize a Task PR's CI observation to JSON for the `ci_observation` column,
/// or `None` when the head has not been observed.
fn task_pr_ci_json(pr: &TaskPr) -> StoreResult<Option<String>> {
    pr.ci_observation
        .as_ref()
        .map(serde_json::to_string)
        .transpose()
        .map_err(StoreError::from)
}

fn task_pr_github_observation_json(pr: &TaskPr) -> StoreResult<Option<String>> {
    pr.github_observation
        .as_ref()
        .map(serde_json::to_string)
        .transpose()
        .map_err(StoreError::from)
}

pub(super) fn task_on(conn: &Connection, task_id: &TaskId) -> StoreResult<Option<Task>> {
    conn.query_row(
        &format!("{TASK_COLUMNS} WHERE t.id=?1"),
        [task_id.as_str()],
        map_task_row,
    )
    .optional()
    .map_err(StoreError::from)
}

fn task_pr_on(conn: &Connection, pr_id: &TaskPrId) -> StoreResult<Option<TaskPr>> {
    conn.query_row(TASK_PR_SELECT, params![pr_id.as_str()], map_task_pr_row)
        .optional()
        .map_err(StoreError::from)
}

fn active_task_pr_on(conn: &Connection, task_id: &TaskId) -> StoreResult<Option<TaskPr>> {
    let query = format!(
        "{TASK_PR_COLUMNS}
         WHERE task_id=?1 AND merge_commit IS NULL AND abandoned_at IS NULL"
    );
    conn.query_row(&query, [task_id.as_str()], map_task_pr_row)
        .optional()
        .map_err(StoreError::from)
}

fn settle_task_pr_on(conn: &Connection, settled: &TaskPr) -> StoreResult<()> {
    let current = task_pr_on(conn, &settled.id)?.ok_or(StoreError::NotFound)?;
    if current.is_settled() {
        if !same_task_pr(&current, settled) {
            return Err(StoreError::InvalidData(format!(
                "Task PR {} is already settled differently",
                settled.id
            )));
        }
    } else if update_task_pr(conn, settled)? == 0 {
        return Err(StoreError::NotFound);
    }
    Ok(())
}

fn validate_task_pr_settlement(settled: &TaskPr, next: Option<&TaskPr>) -> StoreResult<()> {
    validate_task_pr(settled)?;
    if !settled.is_settled() {
        return Err(StoreError::InvalidData(
            "Task PR transition requires a settled PR".to_string(),
        ));
    }
    if let Some(next) = next {
        validate_task_pr(next)?;
        if next.task_id != settled.task_id
            || next.sequence != settled.sequence + 1
            || next.phase() != PrPhase::Working
        {
            return Err(StoreError::InvalidData(
                "next Task PR must be the following Working PR for the same Task".to_string(),
            ));
        }
    }
    Ok(())
}

fn settle_task_pr_in(
    conn: &Connection,
    settled: &TaskPr,
    next: Option<&TaskPr>,
) -> StoreResult<()> {
    settle_task_pr_on(conn, settled)?;
    let Some(next) = next else {
        return Ok(());
    };
    let query = format!("{TASK_PR_COLUMNS} WHERE task_id=?1 AND sequence=?2");
    let existing = conn
        .query_row(
            &query,
            params![next.task_id.as_str(), i64::from(next.sequence)],
            map_task_pr_row,
        )
        .optional()?;
    match existing {
        Some(existing) if same_task_pr(&existing, next) => Ok(()),
        Some(existing) => Err(StoreError::InvalidData(format!(
            "Task PR sequence {} already belongs to {}",
            next.sequence, existing.id
        ))),
        None => insert_task_pr(conn, next),
    }
}

fn settle_task_pr_merged_in(
    conn: &Connection,
    settled: &TaskPr,
    merged_at: Option<OffsetDateTime>,
) -> StoreResult<crate::store::TaskPrMergeEvidenceOutcome> {
    let has_authority_column: bool = conn.query_row(
        "SELECT EXISTS(
             SELECT 1 FROM pragma_table_info('task_prs') WHERE name='merged_at'
         )",
        [],
        |row| row.get(0),
    )?;
    if !has_authority_column {
        settle_task_pr_in(conn, settled, None)?;
        return Ok(crate::store::TaskPrMergeEvidenceOutcome::SchemaUnavailable);
    }

    let accepted_at = conn.query_row(
        "SELECT merged_at FROM task_prs WHERE id=?1",
        [settled.id.as_str()],
        |row| row.get::<_, Option<i64>>(0),
    )?;
    let observed_at = merged_at.map(OffsetDateTime::unix_timestamp);
    let outcome = match (accepted_at, observed_at) {
        (None, Some(_)) => crate::store::TaskPrMergeEvidenceOutcome::Accepted,
        (Some(accepted), Some(observed)) if accepted == observed => {
            crate::store::TaskPrMergeEvidenceOutcome::Repeated
        }
        (Some(accepted), Some(_)) => crate::store::TaskPrMergeEvidenceOutcome::Conflict {
            accepted_at: accepted,
        },
        (_, None) => crate::store::TaskPrMergeEvidenceOutcome::Missing,
    };

    settle_task_pr_in(conn, settled, None)?;
    if let crate::store::TaskPrMergeEvidenceOutcome::Conflict { accepted_at } = outcome {
        let checked_at = settled
            .github_observation
            .as_ref()
            .map(|observation| observation.checked_at)
            .unwrap_or_else(OffsetDateTime::now_utc);
        let observation = GithubObservation {
            checked_at,
            result: crate::work::task::GithubObservationResult::Partial {
                reason: format!(
                    "GitHub merged_at conflicts with first accepted value {accepted_at}"
                ),
            },
        };
        conn.execute(
            "UPDATE task_prs SET github_observation=?2 WHERE id=?1",
            params![settled.id.as_str(), serde_json::to_string(&observation)?],
        )?;
    }
    if let Some(observed_at) = observed_at {
        conn.execute(
            "UPDATE task_prs SET merged_at=COALESCE(merged_at, ?2) WHERE id=?1",
            params![settled.id.as_str(), observed_at],
        )?;
    }
    Ok(outcome)
}

fn same_task_pr(left: &TaskPr, right: &TaskPr) -> bool {
    left.id == right.id
        && left.task_id == right.task_id
        && left.sequence == right.sequence
        && left.slug == right.slug
        && left.branch == right.branch
        && left.base_commit == right.base_commit
        && left.publication == right.publication
        && left.merge_commit == right.merge_commit
        && same_settle_instant(left.abandoned_at, right.abandoned_at)
}

/// The column stores unix seconds, so a settle re-presented with the same
/// wall-clock instant but nanosecond precision is the same settle, not a
/// conflicting one.
fn same_settle_instant(
    left: Option<time::OffsetDateTime>,
    right: Option<time::OffsetDateTime>,
) -> bool {
    left.map(time::OffsetDateTime::unix_timestamp)
        == right.map(time::OffsetDateTime::unix_timestamp)
}

fn invalid_column(
    index: usize,
    error: impl std::error::Error + Send + Sync + 'static,
) -> rusqlite::Error {
    rusqlite::Error::FromSqlConversionFailure(index, rusqlite::types::Type::Text, Box::new(error))
}

fn map_task_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<Task> {
    let abandon_intent = match (
        row.get::<_, Option<i64>>(13)?,
        row.get::<_, Option<String>>(14)?,
    ) {
        (Some(requested_at), Some(reason)) => Some(AbandonIntent {
            requested_at: crate::store::rows::unix_to_datetime(requested_at),
            reason,
        }),
        _ => None,
    };
    Ok(Task {
        id: TaskId::from_raw(row.get::<_, String>(0)?),
        plan: TaskPlan {
            id: LinearIssueId::from_raw(row.get::<_, String>(1)?),
            identifier: row.get(2)?,
            title: row.get(3)?,
            description: row.get(4)?,
            pm_snapshot_synced_at: row.get(10)?,
        },
        pm_writeback: serde_json::from_str(&row.get::<_, String>(11)?)
            .map_err(|error| invalid_column(11, error))?,
        wave_id: row.get(5)?,
        project_id: ProjectId::from_raw(row.get::<_, String>(12)?),
        worktree: PathBuf::from(row.get::<_, String>(6)?),
        workspace_slug: row.get(7)?,
        agent: row.get(15)?,
        abandon_intent,
        created_at: crate::store::rows::unix_to_datetime(row.get(8)?),
        updated_at: crate::store::rows::unix_to_datetime(row.get(9)?),
        // Runtime freshness is derived when reconciliation decides whether the
        // durable GitHub observation can be reused.
        observation: crate::work::task::Observation::NotRequired,
    })
}

fn map_task_pr_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<TaskPr> {
    let publication_requested_at = row.get::<_, Option<i64>>(6)?;
    let after_merge = row
        .get::<_, Option<String>>(7)?
        .map(|value| value.parse())
        .transpose()
        .map_err(|error| invalid_column(7, error))?;
    let github_number = row.get::<_, Option<i64>>(9)?.map(|number| number as u32);
    let github_url = row.get::<_, Option<String>>(10)?;
    let github_head_sha = row.get::<_, Option<String>>(15)?;
    let ci_observation = row
        .get::<_, Option<String>>(16)?
        .map(|json| serde_json::from_str::<CiObservation>(&json))
        .transpose()
        .map_err(|error| invalid_column(16, error))?;
    let github_observation = row
        .get::<_, Option<String>>(18)?
        .map(|json| serde_json::from_str::<GithubObservation>(&json))
        .transpose()
        .map_err(|error| invalid_column(18, error))?;
    let merge = match (
        row.get::<_, Option<String>>(22)?,
        row.get::<_, Option<i64>>(23)?,
        row.get::<_, Option<String>>(24)?,
        after_merge,
    ) {
        (Some(mode), Some(requested_at), Some(head_sha), Some(after_merge)) => {
            Some(PrMergeRequest {
                mode: mode.parse().map_err(|error| invalid_column(22, error))?,
                requested_at: crate::store::rows::unix_to_datetime(requested_at),
                head_sha,
                after_merge,
                next_slug: row.get(8)?,
            })
        }
        (None, None, None, None) => None,
        _ => {
            return Err(invalid_column(
                22,
                std::io::Error::new(
                    std::io::ErrorKind::InvalidData,
                    "PR merge request fields must all be present or absent",
                ),
            ))
        }
    };
    let presentation = match (
        row.get::<_, Option<String>>(25)?,
        row.get::<_, Option<String>>(26)?,
        row.get::<_, Option<String>>(27)?,
    ) {
        (Some(title), Some(body), Some(head_sha)) => Some(PrPresentation {
            title,
            body,
            head_sha,
        }),
        (None, None, None) => None,
        _ => {
            return Err(invalid_column(
                25,
                std::io::Error::new(
                    std::io::ErrorKind::InvalidData,
                    "PR presentation fields must all be present or absent",
                ),
            ))
        }
    };
    let publication = match publication_requested_at {
        Some(requested_at) => Some(PrPublication {
            requested_at: crate::store::rows::unix_to_datetime(requested_at),
            presentation,
            github: match (github_number, github_url) {
                (Some(number), Some(url)) => Some(GithubPr {
                    number,
                    url,
                    head_sha: github_head_sha,
                }),
                (None, None) => None,
                _ => {
                    return Err(invalid_column(
                        9,
                        std::io::Error::new(
                            std::io::ErrorKind::InvalidData,
                            "GitHub PR number and URL must both be present or absent",
                        ),
                    ))
                }
            },
            merge,
        }),
        None => None,
    };
    let pr = TaskPr {
        id: TaskPrId::from_raw(row.get::<_, String>(0)?),
        task_id: TaskId::from_raw(row.get::<_, String>(1)?),
        sequence: row.get::<_, i64>(2)? as u32,
        slug: row.get(3)?,
        branch: row.get(4)?,
        base_commit: row.get(5)?,
        parent_pr_id: row.get::<_, Option<String>>(17)?.map(TaskPrId::from_raw),
        publication,
        merge_commit: row.get(11)?,
        abandoned_at: row
            .get::<_, Option<i64>>(12)?
            .map(crate::store::rows::unix_to_datetime),
        ci_observation,
        github_observation,
        linear_attachment_id: row.get::<_, Option<String>>(19)?,
        linear_comment_id: row.get::<_, Option<String>>(20)?,
        linear_link_error: row.get::<_, Option<String>>(21)?,
        created_at: crate::store::rows::unix_to_datetime(row.get(13)?),
        updated_at: crate::store::rows::unix_to_datetime(row.get(14)?),
    };
    pr.validate_persisted()
        .map_err(|error| invalid_column(6, error))?;
    Ok(pr)
}

fn map_task_linear_observation_row(
    row: &rusqlite::Row<'_>,
) -> rusqlite::Result<TaskLinearObservation> {
    let last_success_at = OffsetDateTime::from_unix_timestamp(row.get::<_, i64>(4)?)
        .map_err(|error| invalid_column(4, error))?;
    let updated_at = OffsetDateTime::from_unix_timestamp(row.get::<_, i64>(6)?)
        .map_err(|error| invalid_column(6, error))?;
    Ok(TaskLinearObservation {
        task_id: TaskId::from_raw(row.get::<_, String>(0)?),
        last_revision: row.get(1)?,
        last_title: row.get(2)?,
        last_description: row.get(3)?,
        last_success_at,
        degraded_reason: row.get(5)?,
        updated_at,
    })
}

fn map_task_event_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<TaskEvent> {
    let kind_json: String = row.get(2)?;
    let kind: TaskEventKind =
        serde_json::from_str(&kind_json).map_err(|error| invalid_column(2, error))?;
    Ok(TaskEvent {
        id: row.get(0)?,
        task_id: TaskId::from_raw(row.get::<_, String>(1)?),
        kind,
        created_at: crate::store::rows::unix_to_datetime(row.get(3)?),
    })
}

pub(super) fn task_events_after_in(
    conn: &Connection,
    task_id: &TaskId,
    cursor: i64,
) -> StoreResult<Vec<TaskEvent>> {
    let mut statement = conn.prepare(
        "SELECT id, task_id, kind_json, created_at
         FROM task_events WHERE task_id=?1 AND id>?2 ORDER BY id",
    )?;
    let rows = statement.query_map(params![task_id.as_str(), cursor], map_task_event_row)?;
    rows.collect::<Result<Vec<_>, _>>()
        .map_err(StoreError::from)
}

const PROJECT_INSERT: &str = "INSERT INTO projects (
    id, wave_id, external_project_id, project_slug, project_name,
    project_prompt_context, pm_snapshot_synced_at,
    abandon_requested_at, abandon_reason,
    created_at, updated_at, iteration, flow, status
) VALUES (
    ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14
)";
const PROJECT_COLUMNS: &str = "SELECT
    id, external_project_id, project_slug, project_name, project_prompt_context,
    wave_id, pm_snapshot_synced_at, abandon_requested_at, abandon_reason,
    created_at, updated_at, iteration, flow, status
    FROM projects";
pub(super) const PROJECT_SELECT: &str = "SELECT
    id, external_project_id, project_slug, project_name, project_prompt_context,
    wave_id, pm_snapshot_synced_at, abandon_requested_at, abandon_reason,
    created_at, updated_at, iteration, flow, status
    FROM projects WHERE id=?1";
const PROJECT_FACT_UPDATE: &str = "UPDATE projects SET
    wave_id=?2, external_project_id=?3, project_slug=?4, project_name=?5,
    project_prompt_context=?6, pm_snapshot_synced_at=?7,
    abandon_requested_at=?8, abandon_reason=?9,
    created_at=?10, updated_at=?11, flow=?12, status=?13
    WHERE id=?1";
fn project_params(project: &Project) -> Vec<Box<dyn ToSql>> {
    vec![
        Box::new(project.id.as_str().to_string()),
        Box::new(project.wave_id.clone()),
        Box::new(project.plan.id.as_str().to_string()),
        Box::new(project.plan.slug.clone()),
        Box::new(project.plan.name.clone()),
        Box::new(project.plan.prompt_context.clone()),
        Box::new(project.plan.pm_snapshot_synced_at),
        Box::new(
            project
                .abandon_intent
                .as_ref()
                .map(|intent| intent.requested_at.unix_timestamp()),
        ),
        Box::new(
            project
                .abandon_intent
                .as_ref()
                .map(|intent| intent.reason.clone()),
        ),
        Box::new(project.created_at.unix_timestamp()),
        Box::new(project.updated_at.unix_timestamp()),
        Box::new(project.iteration),
        Box::new(project.plan.flow.clone()),
        Box::new(project.plan.status.as_str().to_string()),
    ]
}

fn project_fact_params(project: &Project) -> Vec<Box<dyn ToSql>> {
    let mut parameters = project_params(project);
    parameters.remove(11); // Planning refresh cannot overwrite completed judgment passes.
    parameters
}

pub(super) fn map_project_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<Project> {
    let abandon_intent = match (
        row.get::<_, Option<i64>>(7)?,
        row.get::<_, Option<String>>(8)?,
    ) {
        (Some(requested_at), Some(reason)) => Some(AbandonIntent {
            requested_at: crate::store::rows::unix_to_datetime(requested_at),
            reason,
        }),
        _ => None,
    };
    Ok(Project {
        id: ProjectId::from_raw(row.get::<_, String>(0)?),
        plan: ProjectPlan {
            id: LinearProjectId::from_raw(row.get::<_, String>(1)?),
            slug: row.get(2)?,
            name: row.get(3)?,
            prompt_context: row.get(4)?,
            pm_snapshot_synced_at: row.get(6)?,
            flow: row.get(12)?,
            status: serde_json::from_value(serde_json::Value::String(row.get(13)?))
                .map_err(|error| invalid_column(13, error))?,
        },
        wave_id: row.get(5)?,
        iteration: row.get::<_, i64>(11)? as u32,
        abandon_intent,
        created_at: crate::store::rows::unix_to_datetime(row.get(9)?),
        updated_at: crate::store::rows::unix_to_datetime(row.get(10)?),
    })
}

fn map_project_event_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<ProjectEvent> {
    let kind: ProjectEventKind = serde_json::from_str(&row.get::<_, String>(2)?)
        .map_err(|error| invalid_column(2, error))?;
    Ok(ProjectEvent {
        id: row.get(0)?,
        project_id: ProjectId::from_raw(row.get::<_, String>(1)?),
        kind,
        created_at: crate::store::rows::unix_to_datetime(row.get(3)?),
    })
}

pub(super) fn insert_task_event_in(
    conn: &Connection,
    task_id: &TaskId,
    kind: &TaskEventKind,
) -> StoreResult<TaskEvent> {
    let created_at = now_unix();
    if conn.execute(
        "INSERT INTO task_events (task_id, kind_json, created_at)
         SELECT id,?2,?3 FROM tasks WHERE id=?1",
        params![task_id.as_str(), serde_json::to_string(kind)?, created_at],
    )? == 0
    {
        return Err(StoreError::NotFound);
    }
    let event_id = conn.last_insert_rowid();
    Ok(TaskEvent {
        id: event_id,
        task_id: task_id.clone(),
        kind: kind.clone(),
        created_at: crate::store::rows::unix_to_datetime(created_at),
    })
}

pub(super) fn insert_project_event_in(
    conn: &Connection,
    project: &Project,
    kind: &ProjectEventKind,
) -> StoreResult<ProjectEvent> {
    let created_at = now_unix();
    conn.execute(
        "INSERT INTO project_events (project_id, kind_json, created_at)
         VALUES (?1, ?2, ?3)",
        params![
            project.id.as_str(),
            serde_json::to_string(kind)?,
            created_at
        ],
    )?;
    let event_id = conn.last_insert_rowid();
    Ok(ProjectEvent {
        id: event_id,
        project_id: project.id.clone(),
        kind: kind.clone(),
        created_at: crate::store::rows::unix_to_datetime(created_at),
    })
}