From 1984c143ac0b8350446dbd071dbe033dbd0ae11a Mon Sep 17 00:00:00 2001
From: Andrew Calcutt <acalcutt@techidiots.net>
Date: Sat, 7 Oct 2023 01:25:39 -0400
Subject: [PATCH] Revert "feat: failed attempt to load big files"

This reverts commit 727187bd7a2327c9df0b62bbf04cfc523554996f.
---
 src/utils.js | 84 +++++++---------------------------------------------
 1 file changed, 11 insertions(+), 73 deletions(-)

diff --git a/src/utils.js b/src/utils.js
index ac6994c..abe0caa 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -6,7 +6,6 @@ import fs from 'node:fs';
 import clone from 'clone';
 import glyphCompose from '@mapbox/glyph-pbf-composite';
 import PMTiles from 'pmtiles';
-import { decompressSync } from "fflate";
 
 /**
  * Generate new URL object
@@ -166,53 +165,6 @@ export const getFontsPbf = (
   return Promise.all(queue).then((values) => glyphCompose.combine(values));
 };
 
-function readBytes(fd, sharedBuffer) {
-  return new Promise((resolve, reject) => {
-      fs.read(
-          fd, 
-          sharedBuffer,
-          0,
-          sharedBuffer.length,
-          null,
-          (err) => {
-              if(err) { return reject(err); }
-              resolve();
-          }
-      );
-  });
-}
-
-const ReadBytes = async (filePath, offset, size) => {
-  const sharedBuffer = Buffer.alloc(size);
-  const stats = fs.statSync(filePath); // file details
-  const fd = fs.openSync(filePath); // file descriptor
-  let bytesRead = 0; // how many bytes were read
-  let end = size; 
-  
-  for(let i = offset; i < Math.ceil(stats.size / size); i++) {
-      await readBytes(fd, sharedBuffer);
-      bytesRead = (i + 1) * size;
-      if(bytesRead > stats.size) {
-         // When we reach the end of file, 
-         // we have to calculate how many bytes were actually read
-         end = size - (bytesRead - stats.size);
-      }
-      if(bytesRead === size) {break;}
-  }
-
-  return sharedBuffer;
-}
-
-function BufferToArrayBuffer(buffer) {
-  const arrayBuffer = new ArrayBuffer(buffer.length);
-  const view = new Uint8Array(arrayBuffer);
-  for (let i = 0; i < buffer.length; ++i) {
-    view[i] = buffer[i];
-  }
-  const v = new DataView(arrayBuffer);
-  return arrayBuffer;
-}
-
 const PMTilesLocalSource = class {
   constructor(file) {
     this.file = file;
@@ -226,33 +178,19 @@ const PMTilesLocalSource = class {
   }
 };
 
-
-
-
 export const GetPMtilesInfo = async (pmtilesFile) => {
-  var buffer = await ReadBytes(pmtilesFile, 0, 16384)
-  const headerBuf = BufferToArrayBuffer(buffer);
-  const header = PMTiles.bytesToHeader(headerBuf, undefined)
-  const compression = header.internalCompression
-  console.log(header);
-
-  const jsonMetadataOffset = header.jsonMetadataOffset;
-  const jsonMetadataLength = header.jsonMetadataLength;
-  var metadataBytes = await ReadBytes(pmtilesFile, jsonMetadataOffset, jsonMetadataLength)
-  const metadataBuf = BufferToArrayBuffer(metadataBytes);
-
-  console.log(metadataBuf)
-  var metadata;
-  if (compression === PMTiles.Compression.None || compression === PMTiles.Compression.Unknown) {
-    metadata = metadataBuf;
-  } else if (compression === PMTiles.Compression.Gzip) {
-    metadata = decompressSync(new Uint8Array(metadataBuf));
-    console.log(metadata)
-  } else {
-    throw Error("Compression method not supported");
+  const buffer = fs.readFileSync(pmtilesFile)
+  const arrayBuffer = new ArrayBuffer(buffer.length);
+  const view = new Uint8Array(arrayBuffer);
+  for (let i = 0; i < buffer.length; ++i) {
+    view[i] = buffer[i];
   }
+  let source = new PMTilesLocalSource(arrayBuffer);
+  let pmtiles = new PMTiles.PMTiles(source);
 
+  const header = await pmtiles.getHeader();
+  const metadata = await pmtiles.getMetadata();
   const bounds = [header.minLat, header.minLon, header.maxLat, header.maxLon]
-  const center = [header.centerLon, header.centerLat, header.centerLat]
-  return { header: header, metadata: metadata, bounds: bounds, center: center };
+  const center = [header.centerLon, header.centerLat, header.centerZoom]
+  return { source: pmtiles, header: header, metadata: metadata, bounds: bounds, center: center };
 }
\ No newline at end of file