From 1648e70b418d2bbe313e2889fdd7f9ed672f51da Mon Sep 17 00:00:00 2001
From: websmithcode <websmithcode@gmail.com>
Date: Thu, 28 Dec 2023 09:29:59 +0300
Subject: [PATCH] Add `getPagesNumbers` method for parse `pages` arg

---
 CHANGELOG.md                                  |  8 ++-
 README.md                                     | 20 ++++++++
 package.json                                  |  4 +-
 .../get-pages-numbers.spec.ts                 | 49 +++++++++++++++++++
 src/get-pages-numbers/get-pages-numbers.ts    | 30 ++++++++++++
 src/index.ts                                  |  1 +
 6 files changed, 109 insertions(+), 3 deletions(-)
 create mode 100644 src/get-pages-numbers/get-pages-numbers.spec.ts
 create mode 100644 src/get-pages-numbers/get-pages-numbers.ts

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 99b56ff..f07149a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,12 @@
 # Changelog
 
-## [5.7.0](https://www.github.com/websmithcode/pdf-to-printer-modern/compare/v5.6.0...v5.7.0) (2023-12-28)
+## [5.8.0](https://www.github.com/websmithcode/pdf-to-printer-modern/compare/v5.7.0...v5.8.0) (2023-12-28)
+
+### Features
+
+- Add `getPagesNumbers` method for parse `pages` arg
+
+## [5.8.0](https://www.github.com/websmithcode/pdf-to-printer-modern/compare/v5.7.0...v5.8.0) (2023-12-28)
 
 ### Bug Fixes
 
diff --git a/README.md b/README.md
index 64e2689..1f1c322 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,7 @@ If you rely on this package, please consider supporting it. Maintaining an open
     - [`.print(pdf[, options]) => Promise<void>`](#printpdf-options--promisevoid)
     - [`.getPrinters() => Promise<Printer[]>`](#getprinters--promiseprinter)
     - [`.getDefaultPrinter() => Promise<Printer | null>`](#getdefaultprinter--promiseprinter--null)
+    - [`.getPagesNumbers() => numbers[]`](#getpagesnumbers--numbers)
   - [License](#license)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
@@ -148,6 +149,25 @@ import { getDefaultPrinter } from "pdf-to-printer";
 
 getDefaultPrinter().then(console.log);
 ```
+### `.getPagesNumbers() => numbers[]`
+
+A function to get the array that contains numbers of pages.
+
+**Arguments**
+
+1. `pages` (`string`, required): The argument represents pages, that should be print.
+
+**Returns**
+
+`number[]`: a array that contains the numbers of pages.
+
+**Examples**
+
+```javascript
+import { getPagesNumbers } from "pdf-to-printer";
+
+console.log(getPagesNumbers('1-2,4,8-12'));
+```
 
 ## License
 
diff --git a/package.json b/package.json
index 2b1c724..ee99d0e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "pdf-to-printer-moderm",
-  "version": "5.7.0",
+  "version": "5.8.0",
   "description": "A utility for printing PDFs and images from Node.js and Electron.",
   "license": "MIT",
   "repository": {
@@ -59,4 +59,4 @@
     "electron",
     "windows"
   ]
-}
\ No newline at end of file
+}
diff --git a/src/get-pages-numbers/get-pages-numbers.spec.ts b/src/get-pages-numbers/get-pages-numbers.spec.ts
new file mode 100644
index 0000000..5bdc44a
--- /dev/null
+++ b/src/get-pages-numbers/get-pages-numbers.spec.ts
@@ -0,0 +1,49 @@
+import getPagesNumbers from "./get-pages-numbers";
+
+type mockedPagesArgsType = {
+  args: Parameters<typeof getPagesNumbers>;
+  expected: ReturnType<typeof getPagesNumbers> | typeof Error;
+}[];
+
+const mockedPagesArgs = [
+  {
+    args: ["1-3,5,7-9"],
+    expected: [1, 2, 3, 5, 7, 8, 9],
+  },
+  {
+    args: ["1,2,3"],
+    expected: [1, 2, 3],
+  },
+  {
+    args: ["1-3"],
+    expected: [1, 2, 3],
+  },
+  {
+    args: ["1-3,5"],
+    expected: [1, 2, 3, 5],
+  },
+  {
+    args: ["5,1-3"],
+    expected: [5, 1, 2, 3],
+  },
+  {
+    args: ["qwe"],
+    expected: Error,
+  },
+  {
+    args: ["1-3,5,7-9,1e+3"],
+    expected: Error,
+  },
+] as mockedPagesArgsType;
+
+describe("getPagesNumbers", () => {
+  mockedPagesArgs.forEach(({ args, expected }) => {
+    it(`should return ${expected} for ${JSON.stringify(args)}`, () => {
+      if (expected === Error) {
+        expect(() => getPagesNumbers(...args)).toThrow();
+      } else {
+        expect(getPagesNumbers(...args)).toEqual(expected);
+      }
+    });
+  });
+});
diff --git a/src/get-pages-numbers/get-pages-numbers.ts b/src/get-pages-numbers/get-pages-numbers.ts
new file mode 100644
index 0000000..dfaf237
--- /dev/null
+++ b/src/get-pages-numbers/get-pages-numbers.ts
@@ -0,0 +1,30 @@
+export default function getPagesNumbers(pagesString: string) {
+  // parse pages string to array of numbers
+  const pagesArray = pagesString.split(",");
+  const pagesNumbers: number[] = [];
+  pagesArray.forEach((page) => {
+    if (page.includes("-")) {
+      const [start, end] = page.split("-");
+      if (!isNumber(start) || !isNumber(end)) {
+        throw new Error(`Invalid page numbers: ${page}`);
+      }
+
+      const [parsedStart, parsedEnd] = [parseInt(start), parseInt(end)];
+      for (let i = parsedStart; i <= parsedEnd; i++) {
+        pagesNumbers.push(i);
+      }
+    } else {
+      const trimmedPage = page.trim();
+      if (!isNumber(trimmedPage)) {
+        throw new Error(`Invalid page number: ${page}`);
+      }
+      pagesNumbers.push(parseInt(trimmedPage));
+    }
+  });
+
+  return pagesNumbers;
+}
+
+function isNumber(value: string | number): boolean {
+  return value != null && /^\d+$/.test(value.toString());
+}
diff --git a/src/index.ts b/src/index.ts
index ef8fbd0..0f58cd2 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,6 +1,7 @@
 export { default as print } from "./print/print";
 export { default as getPrinters } from "./get-printers/get-printers";
 export { default as getDefaultPrinter } from "./get-default-printer/get-default-printer";
+export { default as getPagesNumbers } from "./get-pages-numbers/get-pages-numbers";
 export { PrintOptions } from "./print/print";
 
 export type Printer = {