Fix slow chatlog queries

Databases can't optimize these month/date extractions so they were
super slow. These queries are instead fast. Assuming the OOM crashes
were due to slow queries, this change should fix them.

(TODO: Figure out why the int cast is necessary.)

server/chat-plugins/chatlog.ts

@@ -87,9 +87,10 @@ export class LogReaderRoom {
 
 	async getLog(day: string) {
 		if (roomlogTable) {
+			const [dayStart, dayEnd] = LogReader.dayToRange(day);
 			const logs = await roomlogTable.selectAll(
 				['log', 'time']
-			)`WHERE roomid = ${this.roomid} AND time::DATE = ${day}`;
+			)`WHERE roomid = ${this.roomid} AND time BETWEEN ${dayStart}::int::timestamp AND ${dayEnd}::int::timestamp`;
 			return new Streams.ObjectReadStream<string>({
 				read(this: Streams.ObjectReadStream<string>) {
 					for (const {log, time} of logs) {
@@ -177,6 +178,23 @@ export const LogReader = new class {
 		return {official, normal, hidden, secret, deleted, personal, deletedPersonal};
 	}
 
+	/** @returns [dayStart, dayEnd] as seconds (NOT milliseconds) since Unix epoch */
+	dayToRange(day: string): [number, number] {
+		const nextDay = LogReader.nextDay(day);
+		return [
+			Math.trunc(new Date(day).getTime() / 1000),
+			Math.trunc(new Date(nextDay).getTime() / 1000),
+		];
+	}
+	/** @returns [monthStart, monthEnd] as seconds (NOT milliseconds) since Unix epoch */
+	monthToRange(month: string): [number, number] {
+		const nextMonth = LogReader.nextMonth(month);
+		return [
+			Math.trunc(new Date(`${month}-01`).getTime() / 1000),
+			Math.trunc(new Date(`${nextMonth}-01`).getTime() / 1000),
+		];
+	}
+
 	getMonth(day?: string) {
 		if (!day) day = Chat.toTimestamp(new Date()).split(' ')[0];
 		return day.slice(0, 7);
@@ -803,14 +821,15 @@ export class RipgrepLogSearcher extends FSLogSearcher {
 }
 
 export class DatabaseLogSearcher extends Searcher {
-	async searchLinecounts(roomid: RoomID, monthString: string, user?: ID) {
+	async searchLinecounts(roomid: RoomID, month: string, user?: ID) {
 		user = toID(user);
 		if (!Rooms.Roomlogs.table) throw new Error(`Database search made while database is disabled.`);
 		const results: {[date: string]: {[user: string]: number}} = {};
-		const [year, month] = monthString.split('-').map(Number);
+		const [monthStart, monthEnd] = LogReader.monthToRange(month);
 		const rows = await Rooms.Roomlogs.table.selectAll()`
-			WHERE EXTRACT("year" FROM time::DATE) = ${year} AND EXTRACT("month" FROM time::DATE) = ${month} AND
-			roomid = ${roomid} AND type = ${'c'}${user ? SQL` AND userid = ${user}` : SQL``}
+			WHERE ${user ? SQL`userid = ${user} AND` : SQL``}roomid = ${roomid} AND
+			time BETWEEN ${monthStart}::int::timestamp AND ${monthEnd}::int::timestamp AND
+			type = ${'c'}
 		`;
 
 		for (const row of rows) {
@@ -823,7 +842,7 @@ export class DatabaseLogSearcher extends Searcher {
 			results[day][row.userid]++;
 		}
 
-		return this.renderLinecountResults(results, roomid, monthString, user);
+		return this.renderLinecountResults(results, roomid, month, user);
 	}
 	activityStats(room: RoomID, month: string): Promise<{average: RoomStats, days: RoomStats[]}> {
 		throw new Chat.ErrorMessage('This is not yet implemented for the new logs database.');