Move database logic into submodule and do simple version check

blahd/schema.sql

@@ -0,0 +1,36 @@
+-- TODO: We are still in prototyping phase. Database migration is not
+-- implemented and layout can change at any time.
+
+CREATE TABLE IF NOT EXISTS `user` (
+    `uid`           INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+    `userkey`       BLOB NOT NULL UNIQUE,
+    `permission`    INTEGER NOT NULL DEFAULT 0
+) STRICT;
+
+CREATE TABLE IF NOT EXISTS `room` (
+    `rid`       INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+    `ruuid`     BLOB NOT NULL UNIQUE,
+    `title`     TEXT NOT NULL,
+    `attrs`     INTEGER NOT NULL
+) STRICT;
+
+CREATE TABLE IF NOT EXISTS `room_member` (
+    `rid`           INTEGER NOT NULL REFERENCES `room` ON DELETE CASCADE,
+    `uid`           INTEGER NOT NULL REFERENCES `user` ON DELETE RESTRICT,
+    `permission`    INTEGER NOT NULL,
+    PRIMARY KEY (`rid`, `uid`)
+) STRICT;
+
+CREATE INDEX IF NOT EXISTS `member_room` ON `room_member` (`uid` ASC, `rid` ASC);
+
+CREATE TABLE IF NOT EXISTS `room_item` (
+    `cid`       INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+    `rid`       INTEGER NOT NULL REFERENCES `room` ON DELETE CASCADE,
+    `uid`       INTEGER NOT NULL REFERENCES `user` ON DELETE RESTRICT,
+    `timestamp` INTEGER NOT NULL,
+    `nonce`     INTEGER NOT NULL,
+    `sig`       BLOB NOT NULL,
+    `rich_text` TEXT NOT NULL
+) STRICT;
+
+CREATE INDEX IF NOT EXISTS `room_latest_item` ON `room_item` (`rid` ASC, `cid` DESC);