-- Backfill actionable notification lifecycle state and business-object links.
-- This migration is deliberately restricted to the verified tjwater_v2 BizDB.

BEGIN;
SET LOCAL lock_timeout = '5s';

DO $$
BEGIN
    IF current_database() <> 'tjwater_v2' THEN
        RAISE EXCEPTION 'Notification lifecycle migration is restricted to tjwater_v2';
    END IF;
END $$;

LOCK TABLE workbench.operational_task_notifications IN SHARE ROW EXCLUSIVE MODE;

CREATE TEMP TABLE notification_lifecycle_projects ON COMMIT DROP AS
SELECT project_id, count(*)::bigint AS notification_count
FROM workbench.operational_task_notifications
GROUP BY project_id;

WITH mapped AS (
    SELECT
        notification.project_id,
        notification.notification_id,
        action.action_id,
        action.approval_status,
        action.execution_status
    FROM workbench.operational_task_notifications AS notification
    LEFT JOIN LATERAL (
        SELECT candidate.action_id, candidate.approval_status, candidate.execution_status
        FROM workbench.operational_task_actions AS candidate
        WHERE candidate.project_id = notification.project_id
          AND candidate.task_id = notification.task_id
          AND 1 = (
              SELECT count(*)
              FROM workbench.operational_task_actions AS sibling
              WHERE sibling.project_id = notification.project_id
                AND sibling.task_id = notification.task_id
          )
        LIMIT 1
    ) AS action ON true
    WHERE notification.document->>'kind' IN (
        'action_pending', 'action_approval_pending', 'external_coordination_failed'
    )
      AND NOT (notification.document ? 'lifecycle_status')
)
UPDATE workbench.operational_task_notifications AS notification
SET document = notification.document || jsonb_strip_nulls(jsonb_build_object(
    'lifecycle_status', CASE
        WHEN mapped.action_id IS NULL THEN 'active'
        WHEN notification.document->>'kind' IN ('action_pending', 'action_approval_pending')
             AND mapped.approval_status = 'pending' THEN 'active'
        WHEN notification.document->>'kind' = 'external_coordination_failed'
             AND mapped.execution_status IN ('failed', 'unsupported', 'unknown') THEN 'active'
        ELSE 'resolved'
    END,
    'subject_type', CASE WHEN mapped.action_id IS NULL THEN 'task' ELSE 'action' END,
    'subject_id', COALESCE(mapped.action_id::text, notification.task_id::text),
    'resolved_at', CASE
        WHEN (notification.document->>'kind' IN ('action_pending', 'action_approval_pending')
              AND mapped.approval_status <> 'pending')
          OR (notification.document->>'kind' = 'external_coordination_failed'
              AND mapped.execution_status NOT IN ('failed', 'unsupported', 'unknown'))
        THEN COALESCE(notification.document->'resolved_at', to_jsonb(CURRENT_TIMESTAMP))
        ELSE NULL
    END,
    'resolution_reason', CASE
        WHEN notification.document->>'resolution_reason' IS NOT NULL
        THEN notification.document->>'resolution_reason'
        WHEN notification.document->>'kind' IN ('action_pending', 'action_approval_pending')
             AND mapped.approval_status <> 'pending' THEN 'migration_action_decided'
        WHEN notification.document->>'kind' = 'external_coordination_failed'
             AND mapped.execution_status NOT IN ('failed', 'unsupported', 'unknown')
        THEN 'migration_external_coordination_recovered'
        ELSE NULL
    END
))
FROM mapped
WHERE notification.project_id = mapped.project_id
  AND notification.notification_id = mapped.notification_id;

DO $block$
BEGIN
    IF to_regclass('workbench.operational_task_access_requests') IS NOT NULL THEN
        EXECUTE $update$
            WITH mapped AS (
                SELECT
                    notification.project_id,
                    notification.notification_id,
                    access_request.access_request_id,
                    access_request.status
                FROM workbench.operational_task_notifications AS notification
                LEFT JOIN LATERAL (
                    SELECT candidate.access_request_id, candidate.status
                    FROM workbench.operational_task_access_requests AS candidate
                    WHERE candidate.project_id = notification.project_id
                      AND candidate.task_id = notification.task_id
                      AND 1 = (
                          SELECT count(*)
                          FROM workbench.operational_task_access_requests AS sibling
                          WHERE sibling.project_id = notification.project_id
                            AND sibling.task_id = notification.task_id
                      )
                    LIMIT 1
                ) AS access_request ON true
                WHERE notification.document->>'kind' = 'access_approval_pending'
                  AND NOT (notification.document ? 'lifecycle_status')
            )
            UPDATE workbench.operational_task_notifications AS notification
            SET document = notification.document || jsonb_strip_nulls(jsonb_build_object(
                'lifecycle_status', CASE
                    WHEN mapped.access_request_id IS NULL OR mapped.status = 'pending'
                    THEN 'active' ELSE 'resolved'
                END,
                'subject_type', CASE
                    WHEN mapped.access_request_id IS NULL THEN 'task'
                    ELSE 'access_request'
                END,
                'subject_id', COALESCE(
                    mapped.access_request_id::text,
                    notification.task_id::text
                ),
                'resolved_at', CASE
                    WHEN mapped.access_request_id IS NOT NULL AND mapped.status <> 'pending'
                    THEN COALESCE(
                        notification.document->'resolved_at',
                        to_jsonb(CURRENT_TIMESTAMP)
                    )
                    ELSE NULL
                END,
                'resolution_reason', CASE
                    WHEN notification.document->>'resolution_reason' IS NOT NULL
                    THEN notification.document->>'resolution_reason'
                    WHEN mapped.status <> 'pending' THEN 'migration_access_request_decided'
                    ELSE NULL
                END
            ))
            FROM mapped
            WHERE notification.project_id = mapped.project_id
              AND notification.notification_id = mapped.notification_id
        $update$;
    END IF;
END $block$;

UPDATE workbench.operational_task_notifications AS notification
SET document = notification.document || jsonb_strip_nulls(jsonb_build_object(
    'lifecycle_status', CASE
        WHEN notification.document->>'kind' = 'task_failed'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') = 'failed'
        THEN 'active'
        WHEN notification.document->>'kind' = 'human_input_required'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') = 'waiting_human'
        THEN 'active'
        WHEN notification.document->>'kind' IN ('task_failed', 'human_input_required')
        THEN 'resolved'
        ELSE COALESCE(notification.document->>'lifecycle_status', 'active')
    END,
    'subject_type', COALESCE(notification.document->>'subject_type', 'task'),
    'subject_id', COALESCE(notification.document->>'subject_id', notification.task_id::text),
    'resolved_at', CASE
        WHEN notification.document->>'kind' = 'task_failed'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') <> 'failed'
        THEN COALESCE(notification.document->'resolved_at', to_jsonb(CURRENT_TIMESTAMP))
        WHEN notification.document->>'kind' = 'human_input_required'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') <> 'waiting_human'
        THEN COALESCE(notification.document->'resolved_at', to_jsonb(CURRENT_TIMESTAMP))
        ELSE notification.document->'resolved_at'
    END,
    'resolution_reason', CASE
        WHEN notification.document->>'kind' = 'task_failed'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') <> 'failed'
        THEN 'migration_task_recovered'
        WHEN notification.document->>'kind' = 'human_input_required'
             AND COALESCE(task.document->>'lifecycle_status', task.document->>'status') <> 'waiting_human'
        THEN 'migration_human_input_completed'
        ELSE notification.document->>'resolution_reason'
    END
))
FROM workbench.operational_tasks AS task
WHERE notification.project_id = task.project_id
  AND notification.task_id = task.task_id
  AND notification.document->>'kind' NOT IN (
      'action_pending', 'action_approval_pending',
      'external_coordination_failed', 'access_approval_pending'
  )
  AND NOT (notification.document ? 'lifecycle_status');

WITH inserted_events AS (
    INSERT INTO workbench.domain_event_log (
        project_id,
        event_id,
        topic,
        aggregate_type,
        aggregate_id,
        aggregate_revision,
        metadata
    )
    SELECT
        project_id,
        (
            substr(md5(project_id::text || ':notification-lifecycle-v1'), 1, 8)
            || '-' || substr(md5(project_id::text || ':notification-lifecycle-v1'), 9, 4)
            || '-5' || substr(md5(project_id::text || ':notification-lifecycle-v1'), 14, 3)
            || '-a' || substr(md5(project_id::text || ':notification-lifecycle-v1'), 18, 3)
            || '-' || substr(md5(project_id::text || ':notification-lifecycle-v1'), 21, 12)
        )::uuid,
        'operational.notification.changed',
        'operational_notification_batch',
        project_id::text,
        1,
        jsonb_build_object(
            'change', 'lifecycle_backfilled',
            'notification_count', notification_count
        )
    FROM notification_lifecycle_projects
    ON CONFLICT (project_id, event_id) DO NOTHING
    RETURNING project_id, event_seq
)
SELECT pg_notify('workbench_events', project_id::text || ':' || event_seq::text)
FROM inserted_events;

COMMENT ON COLUMN workbench.operational_task_notifications.document IS
    '通知内容及 active/resolved 生命周期；用户 unread/read 状态独立存于 notification_reads。';

COMMIT;