[node] implement shipyard info retrieval and database caching

nodejs/database/005_shipyards.sql

@@ -0,0 +1,6 @@
+CREATE TABLE shipyards (
+       id INTEGER PRIMARY KEY,
+       data JSON NOT NULL,
+       updated DATE DEFAULT NULL
+);
+CREATE UNIQUE INDEX shipyards_data_symbol on shipyards (json_extract(data, '$.symbol'));

nodejs/database/shipyards.ts

@@ -0,0 +1,27 @@
+import { DbData, db } from './db.ts';
+import { Shipyard } from '../lib/types';
+
+const addStatement = db.prepare(`INSERT INTO shipyards(data, updated) VALUES (json(:data), :date);`);
+const getStatement = db.prepare(`SELECT data FROM shipyards WHERE data->>'symbol' = ?;`);
+const updateStatement = db.prepare(`UPDATE shipyards SET data = json(:data), updated = :date WHERE data->>'symbol' = :symbol;`);
+
+export function get(symbol: string): Shipyard|null {
+	const data = getStatement.get(symbol) as DbData|undefined;
+	if (!data) return null;
+	return JSON.parse(data.data);
+}
+
+export function set(data: Shipyard): void {
+    if (get(data.symbol) === null) {
+		addStatement.run({
+			data: JSON.stringify(data),
+			date: new Date().toISOString(),
+		});
+    } else {
+		updateStatement.run({
+			data: JSON.stringify(data),
+			date: new Date().toISOString(),
+			symbol: data.symbol,
+		});
+	}
+}

nodejs/lib/systems.ts

@@ -4,17 +4,22 @@ import {
 	sendPaginated,
 } from './api.ts';
 import * as dbMarkets from '../database/markets.ts';
+import * as dbShipyards from '../database/shipyards.ts';
 import * as dbSystems from '../database/systems.ts';
 import {
 	Market,
+	Shipyard,
 	System,
 	Waypoint,
 } from './types.ts'
-import { systemFromWaypoint } from './utils.ts';
+import {
+	isThereAShipAtThisWaypoint,
+	systemFromWaypoint,
+} from './utils.ts';
 
 export async function market(waypoint: Waypoint): Promise<Market> {
     const data = dbMarkets.getMarketAtWaypoint(waypoint.symbol);
-	if (data) { return data; }
+	if (data && (data.tradeGoods || !isThereAShipAtThisWaypoint(waypoint))) { return data; }
 	const systemSymbol = systemFromWaypoint(waypoint.symbol);
 	let response = await send<Market>({endpoint: `/systems/${systemSymbol}/waypoints/${waypoint.symbol}/market`});
 	if (response.error) {
@@ -25,11 +30,18 @@ export async function market(waypoint: Waypoint): Promise<Market> {
 	return response.data;
 }
 
-//export async function shipyard(waypoint: string): Promise<unknown> {
-//	// TODO database caching
-//	const systemSymbol = systemFromWaypoint(waypoint);
-//	return await send({endpoint: `/systems/${systemSymbol}/waypoints/${waypoint}/shipyard`});
-//}
+export async function shipyard(waypoint: Waypoint): Promise<Shipyard> {
+	const data = dbShipyards.get(waypoint.symbol);
+	if (data && (data.ships || !isThereAShipAtThisWaypoint(waypoint))) { return data; }
+	const systemSymbol = systemFromWaypoint(waypoint.symbol);
+	const response = await send<Shipyard>({endpoint: `/systems/${systemSymbol}/waypoints/${waypoint.symbol}/shipyard`});
+	if (response.error) {
+		debugLog(response);
+		throw response;
+	}
+	dbShipyards.set(response.data);
+	return response.data;
+}
 
 export async function system(symbol: string): Promise<System> {
 	let data = dbSystems.getSystem(symbol);

nodejs/lib/types.ts

@@ -80,6 +80,29 @@ export type RouteEndpoint = {
 	y: number;
 };
 
+export type Shipyard = {
+	modificationFee: number;
+	ships: Array<ShipyardShip>;
+	shipTypes: Array<{type: string}>;
+	symbol: string;
+	//transactions: Array<Transaction>;
+};
+
+export type ShipyardShip = {
+    activity: string;
+	// crew
+    description: string;
+	// engine
+	// frame
+	// modules
+	// mounts
+    name: string;
+    purchasePrice: number;
+	// reactor
+    supply: string;
+    type: string;
+};
+
 export type System = {
 	symbol: string;
 	sectorSymbol: string;

nodejs/lib/utils.ts

@@ -2,9 +2,8 @@ import {
 	debugLog,
 } from './api.ts';
 import { PriorityQueue } from './priority_queue.ts';
-import {
-	market,
-} from './systems.ts';
+import { getShips } from './ships.ts';
+import { market } from './systems.ts';
 import {
 	Cargo,
 	CargoManifest,
@@ -41,6 +40,10 @@ export function distance(a: Point, b: Point) {
 	return Math.sqrt((a.x-b.x)**2 + (a.y-b.y)**2);
 }
 
+export function isThereAShipAtThisWaypoint(waypoint: Waypoint): boolean {
+	return getShips().some(s => s.nav.waypointSymbol === waypoint.symbol);
+}
+
 export function sortByDistanceFrom<T extends Point>(a: Point, points: Array<T>): Array<{data: T, distance: number}>{
 	let result = points.map(function (m) { return {
 		data: m,