Allow custom qpdf binary

[luicfrr]

With this we can pass a custom qpdf binary path.
If user wants to use source compiled or standalone versions of qpdf binaries.

In my case I needed to use the standalone Linux binary release because qpdf cannot be installed nor used as a layer.
Here's an example of usage:

await encrypt( {
  // path where qpdf binary is located
  qpdfPath: path/to/qpdf/bin,
  ... other props
})

[luicfrr]

While this don't get merged, here's a patch I've made in case of anyone need:

diff --git a/node_modules/node-qpdf2/dist/decrypt.d.ts b/node_modules/node-qpdf2/dist/decrypt.d.ts
index 32909cc..df98587 100644
--- a/node_modules/node-qpdf2/dist/decrypt.d.ts
+++ b/node_modules/node-qpdf2/dist/decrypt.d.ts
@@ -1,5 +1,7 @@
 /// <reference types="node" resolution-mode="require"/>
 export interface DecryptSettings {
+    /** Path to custom qpdf binary */
+    qpdfPath?: string
     /** The path for the encrypted pdf */
     input: string;
     /** The path for the decrypted pdf */
diff --git a/node_modules/node-qpdf2/dist/decrypt.js b/node_modules/node-qpdf2/dist/decrypt.js
index c44ca6a..d2f4994 100644
--- a/node_modules/node-qpdf2/dist/decrypt.js
+++ b/node_modules/node-qpdf2/dist/decrypt.js
@@ -24,5 +24,5 @@ export const decrypt = async (payload) => {
     else {
         callArguments.push("-");
     }
-    return execute(callArguments);
+    return execute(callArguments, payload.qpdfPath);
 };
diff --git a/node_modules/node-qpdf2/dist/encrypt.d.ts b/node_modules/node-qpdf2/dist/encrypt.d.ts
index 10d7a72..3440f50 100644
--- a/node_modules/node-qpdf2/dist/encrypt.d.ts
+++ b/node_modules/node-qpdf2/dist/encrypt.d.ts
@@ -1,5 +1,7 @@
 /// <reference types="node" resolution-mode="require"/>
 export interface EncryptOptions {
+    /** Path to custom qpdf binary */
+    qpdfPath?: string
     /** The location of the unencrypted pdf file */
     input: string;
     /**
@@ -43,7 +45,7 @@ export interface EncryptOptions {
         /** Please see: https://qpdf.readthedocs.io/en/stable/cli.html#option-modify-other */
         modifyOther?: "y" | "n";
         /** Please see: https://qpdf.readthedocs.io/en/stable/cli.html#option-print */
-        print?: "y" | "n" | "full" | "low" | "none";
+        print?: "full" | "low" | "none";
         /** Please see: https://qpdf.readthedocs.io/en/stable/cli.html#option-use-aes */
         useAes?: "y" | "n";
     };
diff --git a/node_modules/node-qpdf2/dist/encrypt.js b/node_modules/node-qpdf2/dist/encrypt.js
index 3009281..f0064ee 100644
--- a/node_modules/node-qpdf2/dist/encrypt.js
+++ b/node_modules/node-qpdf2/dist/encrypt.js
@@ -21,9 +21,9 @@ export const encrypt = async (userPayload) => {
     if (payload.output && !payload.overwrite && fileExists(payload.output))
         throw new Error("Output file already exists");
     const callArguments = [];
-    // If the keyLength is 40, `--allow-weak-crypto` needs to be specified before `--encrypt`.
+    // If the keyLength is not 256, `--allow-weak-crypto` needs to be specified before `--encrypt`.
     // This is required for qpdf 11+.
-    if (payload.keyLength === 40)
+    if (payload.keyLength !== 256)
         callArguments.push("--allow-weak-crypto");
     callArguments.push("--encrypt");
     // Set user-password and owner-password
@@ -78,5 +78,5 @@ export const encrypt = async (userPayload) => {
         callArguments.push("-");
     }
     // Execute command and return stdout for pipe
-    return execute(callArguments);
+    return execute(callArguments, payload.qpdfPath);
 };
diff --git a/node_modules/node-qpdf2/dist/info.d.ts b/node_modules/node-qpdf2/dist/info.d.ts
index 263ded6..a1877b0 100644
--- a/node_modules/node-qpdf2/dist/info.d.ts
+++ b/node_modules/node-qpdf2/dist/info.d.ts
@@ -1,4 +1,6 @@
 export interface InfoSettings {
+    /** Path to custom qpdf binary */
+    qpdfPath?: string
     /** The path for the encrypted pdf */
     input: string;
     /** The password for the encrypted pdf */
diff --git a/node_modules/node-qpdf2/dist/info.js b/node_modules/node-qpdf2/dist/info.js
index 7424797..b65020c 100644
--- a/node_modules/node-qpdf2/dist/info.js
+++ b/node_modules/node-qpdf2/dist/info.js
@@ -17,6 +17,6 @@ export const info = async (payload) => {
     }
     // Input file path
     callArguments.push(payload.input);
-    const result = await execute(callArguments);
+    const result = await execute(callArguments, payload.qpdfPath);
     return result.toLocaleString().trim();
 };
diff --git a/node_modules/node-qpdf2/dist/spawn.d.ts b/node_modules/node-qpdf2/dist/spawn.d.ts
index 2b93ec5..47fa939 100644
--- a/node_modules/node-qpdf2/dist/spawn.d.ts
+++ b/node_modules/node-qpdf2/dist/spawn.d.ts
@@ -1,3 +1,3 @@
 /// <reference types="node" resolution-mode="require"/>
-declare const _default: (callArguments: string[]) => Promise<Buffer>;
-export default _default;
+declare const _default: ( callArguments: string[], qpdfPath?: string ) => Promise<Buffer>
+export default _default
diff --git a/node_modules/node-qpdf2/dist/spawn.js b/node_modules/node-qpdf2/dist/spawn.js
index 21377c8..dc594e2 100644
--- a/node_modules/node-qpdf2/dist/spawn.js
+++ b/node_modules/node-qpdf2/dist/spawn.js
@@ -1,8 +1,10 @@
 // Ignore errors about unsafe-arguments, this is because data is unknown
 /* eslint-disable @typescript-eslint/no-unsafe-argument */
 import { spawn } from "node:child_process";
-export default (callArguments) => new Promise((resolve, reject) => {
-    const process = spawn("qpdf", callArguments);
+export default (callArguments, qpdfPath) => new Promise((resolve, reject) => {
+    const process = spawn(qpdfPath? "./qpdf" : "qpdf", callArguments, {
+      cwd: qpdfPath
+    });
     const stdout = [];
     const stderr = [];
     process.stdout.on("data", (data) => {

[luicfrr]

@Sparticuz Can you please take a look to merge this?
Thanks 😁

[Sparticuz]

Thanks for the PR! Sorry it was a little bit before I could look at it.

My main question is this. Can't you just add that directory to PATH?

EDIT: what I mean by that is something like this

process.env["PATH"] = `${process.env["PATH"]}:${path.join(process.cwd(),"qpdf_dir","bin")}`

[Sparticuz]

I've added a few notes. Thanks!

[luicfrr]

Thanks for the PR! Sorry it was a little bit before I could look at it.

My main question is this. Can't you just add that directory to PATH?

EDIT: what I mean by that is something like this

process.env["PATH"] = `${process.env["PATH"]}:${path.join(process.cwd(),"qpdf_dir","bin")}`

I'll see if can manage it to work using your suggestion.
At this moment I'm using the pacakge with PR changes and it's working nice.