-- Private messages are deliberately excluded from the project event log.
BEGIN;

CREATE TABLE IF NOT EXISTS workbench.agent_messages (
    project_id uuid NOT NULL,
    message_id uuid NOT NULL,
    request_id uuid NOT NULL,
    task_id uuid NOT NULL,
    run_id uuid NOT NULL,
    source_session_id text NOT NULL CHECK (length(source_session_id)>0),
    source_owner_id uuid NOT NULL,
    conversation_owner_id uuid NOT NULL,
    target_session_id text,
    direction text NOT NULL CHECK (direction IN ('to_task','to_chat')),
    in_reply_to uuid,
    text text NOT NULL CHECK (length(text) BETWEEN 1 AND 12000 AND text ~ '\S'),
    status text NOT NULL CHECK (status IN ('pending','enqueued','delivered','failed')),
    native_message_id text NOT NULL,
    failure_detail text,
    created_at timestamptz NOT NULL,
    updated_at timestamptz NOT NULL,
    delivered_at timestamptz,
    PRIMARY KEY (project_id,message_id),
    UNIQUE (project_id,source_owner_id,source_session_id,request_id),
    FOREIGN KEY (project_id,task_id)
        REFERENCES workbench.operational_tasks(project_id,task_id),
    FOREIGN KEY (project_id,run_id)
        REFERENCES workbench.operational_task_runs(project_id,run_id),
    FOREIGN KEY (project_id,in_reply_to)
        REFERENCES workbench.agent_messages(project_id,message_id),
    CHECK ((direction='to_task')
        OR (direction='to_chat' AND in_reply_to IS NOT NULL AND target_session_id IS NOT NULL))
);
CREATE INDEX IF NOT EXISTS agent_messages_pending_idx
    ON workbench.agent_messages(project_id,created_at,message_id)
    WHERE status IN ('pending','enqueued');
CREATE INDEX IF NOT EXISTS agent_messages_owner_session_idx
    ON workbench.agent_messages(project_id,conversation_owner_id,created_at);
CREATE INDEX IF NOT EXISTS agent_messages_run_idx
    ON workbench.agent_messages(project_id,run_id,status);

COMMIT;