From 45fdf1904d3ef259485c1c54f1a47206e4298024 Mon Sep 17 00:00:00 2001
From: Fred Boniface <fred@fjla.uk>
Date: Thu, 12 Oct 2023 21:56:58 +0100
Subject: [PATCH] Add pipeline for partial PIS match

Signed-off-by: Fred Boniface <fred@fjla.uk>
---
 app.js                       |  1 -
 src/services/pis.services.ts | 54 ++++++++++++++++++++++++++++++++++--
 2 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/app.js b/app.js
index 3e8e348..2485165 100644
--- a/app.js
+++ b/app.js
@@ -72,7 +72,6 @@ app.use("/api/v2/timetable", tt2Rtr); // API Version 2
 app.use("/api/v2/user", user2Rtr); // API Version 2
 app.use("/misc", miscRtr); // Non public-api endpoints (Stats, Issue, etc.)
 
-
 app.use("/api/v1/auth/test", authenticate, (req, res) =>
   res.status(200).json({
     status: "ok",
diff --git a/src/services/pis.services.ts b/src/services/pis.services.ts
index b974cf3..e9b3449 100644
--- a/src/services/pis.services.ts
+++ b/src/services/pis.services.ts
@@ -4,6 +4,7 @@ const db = require("../services/dbAccess.services");
 const clean = require("../utils/sanitizer.utils");
 
 import { logger } from "../utils/logger.utils";
+import { queryAggregate } from "./dbAccess.services";
 
 const supported = ["GW", "UK"];
 
@@ -47,19 +48,66 @@ async function findByTiplocArray(tiplocArray: string[]) {
   };
   const res = await db.query("pis", query);
   // If res is empty then try to find partial match
-  /* if (res.length) {
+  if (res.length) {
     return res;
   } else {
     let partial = await findPartialMatchByTiploc(tiplocArray);
     return partial
-  } */
-  return await res;
+  }
 }
 
 async function findPartialMatchByTiploc(tiplocArray: string[]) {
   // Do some magic here, similar to findPisByOrigDest but
   // ensuring that the stops in the array match the last
   // x number of items in the array.
+
+  const pipeline = [
+    {
+      $addFields: {
+        reversedStops: {
+          $reverseArray: "$stops",
+        },
+        reversedQueryArray: {
+          $reverseArray: tiplocArray,
+        },
+      },
+    },
+    {
+      $match: {
+        $expr: {
+          $gt: [
+            {
+              $indexOfArray: [
+                "$reversedStops",
+                {
+                  $arrayElemAt: ["$reversedQueryArray", 0],
+                }
+              ],
+            },
+            -1,
+          ],
+        },
+      },
+    },
+    {
+      $project: {
+        code: 1,
+        skipStops: {
+          $subtract: [
+            {
+              $size: "$stops",
+            },
+            {
+              $size: tiplocArray,
+            },
+          ],
+        },
+      },
+    },
+  ];
+
+  const res = await queryAggregate('pis', pipeline)
+  console.log(JSON.stringify(res))
 }
 
 module.exports = {