-- R720 agent-team durable SQLite schema (design §3.3.1, §6.7).
--
-- This file holds the raw DDL statements ONLY. The authoritative copies live
-- as string constants in agent_team/db/schema.py; this companion file mirrors
-- them verbatim for tooling / direct inspection. SQL DDL lives only in these
-- two places.
--
-- The LangGraph SqliteSaver checkpointer creates its OWN tables against this
-- same database file/connection; those are intentionally NOT declared here.

-- pending_questions: the durable human-interaction lifecycle ledger.
-- The LangGraph checkpoint holds graph state; this table holds the question
-- lifecycle (delivery, duplicate/late answers, expiry) and is what delivery,
-- the responder, and restart recovery read. Every race resolves via an atomic
-- compare-and-set against the `status` column under BEGIN IMMEDIATE.
CREATE TABLE IF NOT EXISTS pending_questions (
    question_id   TEXT PRIMARY KEY,
    thread_id     TEXT NOT NULL,
    turn          INTEGER NOT NULL,
    status        TEXT NOT NULL
                  CHECK (status IN ('open', 'answered', 'expired', 'superseded')),
    transport     TEXT NOT NULL,
    channel_ref   TEXT,
    posted_at     TEXT,
    deadline_at   TEXT,
    answer_json   TEXT,
    answered_at   TEXT,
    answered_via  TEXT
);

CREATE INDEX IF NOT EXISTS idx_pending_questions_thread
    ON pending_questions (thread_id, turn);

CREATE INDEX IF NOT EXISTS idx_pending_questions_status
    ON pending_questions (status);

-- Defense-in-depth: at most one OPEN question may carry a given non-null
-- channel_ref, so a thread reply's thread_ts can never map to two open rows
-- (a partial unique index; NULL channel_refs and closed rows are excluded).
CREATE UNIQUE INDEX IF NOT EXISTS uq_pending_questions_open_channel_ref
    ON pending_questions (channel_ref)
    WHERE channel_ref IS NOT NULL AND status = 'open';

-- budget_ledger: the persistent shared Claude budget ledger (§6.1, §6.6).
-- One row per accounted spend event; the shared daily cap and the
-- interactive-first reserve are computed by summing over a UTC day. Spend is
-- recorded across ALL R720 Claude work (pipeline + Plane-1 sweeps).
CREATE TABLE IF NOT EXISTS budget_ledger (
    entry_id        INTEGER PRIMARY KEY AUTOINCREMENT,
    thread_id       TEXT,
    stage           TEXT,
    model           TEXT NOT NULL,
    billing_mode    TEXT NOT NULL,
    input_tokens    INTEGER NOT NULL DEFAULT 0,
    output_tokens   INTEGER NOT NULL DEFAULT 0,
    usd_cost        REAL NOT NULL DEFAULT 0.0,
    recorded_at     TEXT NOT NULL,
    day_bucket      TEXT NOT NULL
);

CREATE INDEX IF NOT EXISTS idx_budget_ledger_day
    ON budget_ledger (day_bucket);

CREATE INDEX IF NOT EXISTS idx_budget_ledger_thread
    ON budget_ledger (thread_id);

-- ingested_issues (schema v2): durable de-dup ledger for the GitHub-issue intake
-- poller. The in-memory poller set does not survive a restart, so a scheduled
-- intake (each run a fresh process) would re-ingest every still-open labeled
-- issue and spawn duplicate tasks. This table records, per (source, issue_id),
-- the issues already turned into tasks so intake is idempotent across restarts.
-- The box is read-only (no write token to remove the intake label), so durable
-- de-dup is the only correct guard. `source` namespaces by repo (e.g.
-- "github:owner/repo") so per-repo issue numbers from different repos cannot collide.
CREATE TABLE IF NOT EXISTS ingested_issues (
    source       TEXT NOT NULL,
    issue_id     TEXT NOT NULL,
    ingested_at  TEXT NOT NULL,
    PRIMARY KEY (source, issue_id)
);

-- schema_meta: single-row table recording the applied schema version so
-- migrate() can detect and step forward.
CREATE TABLE IF NOT EXISTS schema_meta (
    id              INTEGER PRIMARY KEY CHECK (id = 1),
    schema_version  INTEGER NOT NULL
);