From 466981457d95cd77beb2ca011cf290b41a90744d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adam=20Kr=C5=A1ka?= <adam@krska.com>
Date: Sat, 14 Sep 2024 16:01:51 +0200
Subject: [PATCH] calculate new points

---
 src/gambleMath.ts       | 54 +++++++++++++++++++++++++++++++++++++++++
 src/index.ts            | 25 +++++++++++++------
 src/templates/index.ejs |  1 -
 3 files changed, 72 insertions(+), 8 deletions(-)
 create mode 100644 src/gambleMath.ts

diff --git a/src/gambleMath.ts b/src/gambleMath.ts
new file mode 100644
index 0000000..c642e25
--- /dev/null
+++ b/src/gambleMath.ts
@@ -0,0 +1,54 @@
+const deltaX: number = 10;
+const ymax: number = 1;
+
+function f(a: number, x: number): number {
+	return Math.exp(-1 * Math.pow((x - a), 2) / 20);
+}
+
+// helper function
+function randomRange(min: number, max: number): number {
+	return min + Math.random() * (max - min);
+}
+
+let numberOfInterations = 0;
+export default function calculateNewPoints(currentPoints: number): number {
+	let randomX: number;
+	let randomY: number;
+	do {
+		numberOfInterations++;
+		randomX = randomRange(currentPoints - deltaX, currentPoints + deltaX);
+		randomY = randomRange(0, ymax);
+	} while (f(currentPoints, randomX) <= randomY)
+
+	return randomX;
+}
+
+// testing functions
+//let stats = new Map<number, number>();
+//let points = new Map<number, number>();
+//for (let i = 0; i < 1000; i++) {
+//	numberOfInterations = 0;
+//	let p = Math.round(calculateNewPoints(100));
+//
+//	if (stats.has(numberOfInterations)) {
+//		let iters = stats.get(numberOfInterations) + 1;
+//		stats.set(numberOfInterations, iters);
+//	} else {
+//		stats.set(numberOfInterations, 1);
+//	}
+//
+//
+//	if (points.has(p)) {
+//		let po = points.get(p) + 1;
+//		console.log(po);
+//		points.set(p, po);
+//	} else {
+//		points.set(p, 1);
+//	}
+//}
+//
+//console.log("iterace (počet iterací, počet výskytů):");
+//console.log(new Map([...stats.entries()].sort()));
+//console.log("body (počet bodů, počet výskytů):");
+//console.log(new Map([...points.entries()].sort()));
+//
diff --git a/src/index.ts b/src/index.ts
index 86f3843..2bd051b 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -2,8 +2,9 @@ import express from "express";
 import ejs from "ejs";
 import multer from "multer";
 import { db } from "./database/db";
-import { eq, sql, sum } from "drizzle-orm";
+import { eq, sql } from "drizzle-orm";
 import { personTable, pointsTable } from "./database/schema";
+import calculateNewPoints from "./gambleMath";
 
 const app = express();
 const port = 8080;
@@ -15,8 +16,7 @@ app.use(express.static('www'));
 app.get("/", async (req, res) => {
 	const people = await db.select({
 		personId: personTable.personId,
-		name: personTable.name,
-		pointsTotal: sql`coalesce(sum(${pointsTable.points}), 0)`
+		name: personTable.name
 	}).from(personTable)
 		.leftJoin(pointsTable, eq(personTable.personId, pointsTable.personId))
 		.groupBy(personTable.personId)
@@ -103,9 +103,16 @@ app.post("/gamble/:id", upload.none(), async (req, res) => {
 		return;
 	}
 
-	let person = await db.query.personTable.findFirst({
-		where: eq(personTable.personId, id)
-	})
+	let person = (await db.select({
+		personId: personTable.personId,
+		name: personTable.name,
+		secret: personTable.secret,
+		gambleTime: personTable.gambleTime,
+		pointsTotal: sql<string>`coalesce(sum(${pointsTable.points}), 0)`
+	}).from(personTable)
+		.leftJoin(pointsTable, eq(personTable.personId, pointsTable.personId))
+		.where(eq(personTable.personId, id))
+		.groupBy(personTable.personId))[0];
 
 	if (!person) {
 		res.status(404).send("Invalid person id");
@@ -122,6 +129,10 @@ app.post("/gamble/:id", upload.none(), async (req, res) => {
 		return;
 	}
 
+	let currentPoints = parseInt(person.pointsTotal);
+	let newTotalPoints = calculateNewPoints(currentPoints);
+	let pointsDiff = newTotalPoints - currentPoints;
+
 	await db.update(personTable)
 		.set({
 			gambleTime: sql`NOW()`
@@ -130,7 +141,7 @@ app.post("/gamble/:id", upload.none(), async (req, res) => {
 
 	await db.insert(pointsTable).values({
 		personId: id,
-		points: req.body['points']
+		points: pointsDiff
 	})
 
 	res.redirect('/person/' + id);
diff --git a/src/templates/index.ejs b/src/templates/index.ejs
index acf7a3c..50d42fe 100644
--- a/src/templates/index.ejs
+++ b/src/templates/index.ejs
@@ -10,7 +10,6 @@
 </head>
 
 <body data-bs-theme="dark">
-	<a href="/gamble">gamble</a>
 	People
 	<div class="row p-5">
 		<div class="list-group col-3">