--
-- Scrape cache + per-attachment scrape lifecycle.
--
-- This file is the human-readable record. It is NOT applied by hand: the same
-- statements live in server/helpers/Schema.js and are applied idempotently at
-- boot after an information_schema existence check, so dev and prod converge
-- without a migration runner.
--
-- Portability: dev is MariaDB 11.4, prod is MySQL 8. Nothing here may use
-- ADD COLUMN IF NOT EXISTS (MariaDB-only).
--

-- One row per URL, shared across users and notes. url_hash carries the UNIQUE
-- index because a UNIQUE on varchar(1000) utf8mb4 is 4000 bytes and exceeds
-- InnoDB's 3072-byte key limit.
CREATE TABLE IF NOT EXISTS `scrape_cache` (
  `id`            int(10) unsigned NOT NULL AUTO_INCREMENT,
  `url_hash`      char(64) NOT NULL,
  `url`           varchar(1000) NOT NULL DEFAULT '',
  `canonical_url` varchar(1000) DEFAULT NULL,
  `status`        smallint(6) NOT NULL DEFAULT 0,
  `title`         varchar(512) DEFAULT NULL,
  `site_name`     varchar(255) DEFAULT NULL,
  `description`   mediumtext DEFAULT NULL,
  `keywords`      varchar(512) DEFAULT NULL,
  `search_text`   mediumtext DEFAULT NULL,
  `image_url`     varchar(1000) DEFAULT NULL,
  `file_location` varchar(500) DEFAULT NULL,
  `etag`          varchar(255) DEFAULT NULL,
  `last_modified` varchar(128) DEFAULT NULL,
  `content_type`  varchar(128) DEFAULT NULL,
  `fetch_state`   varchar(20) NOT NULL DEFAULT 'pending',
  `failure_count` int(11) NOT NULL DEFAULT 0,
  `last_error`    varchar(255) DEFAULT NULL,
  `fetched_at`    int(11) DEFAULT NULL,
  `expires_at`    int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `scrape_cache_url_hash` (`url_hash`),
  KEY `scrape_cache_expires_at` (`expires_at`),
  KEY `scrape_cache_fetch_state` (`fetch_state`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- Per-attachment lifecycle, so an in-memory queue survives a restart.
--
-- scrape_state: 0 = pending, 1 = fetching, 2 = done, 3 = failed.
-- DEFAULT 2 is load-bearing: it keeps the ~2200 pre-existing rows out of the
-- recovery sweep on first boot.
ALTER TABLE `attachment` ADD COLUMN `scrape_state`    tinyint(4) NOT NULL DEFAULT 2;
ALTER TABLE `attachment` ADD COLUMN `scrape_attempts` tinyint(4) NOT NULL DEFAULT 0;
ALTER TABLE `attachment` ADD COLUMN `enqueued_at`     int(11) DEFAULT NULL;
ALTER TABLE `attachment` ADD KEY `attachment_scrape_state` (`scrape_state`, `enqueued_at`);