From edee1a106788e839651c1bc12269bd375d695d0d Mon Sep 17 00:00:00 2001
From: Mmis1000 <mmis10002@gmail.com>
Date: Sun, 13 Sep 2020 21:33:32 +0800
Subject: [PATCH] Handle alt screen

---
 .../src/SerializeAddon.ts                     | 28 +++++++++++++---
 .../test/SerializeAddon.api.ts                | 32 +++++++++++++++++++
 2 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/addons/xterm-addon-serialize/src/SerializeAddon.ts b/addons/xterm-addon-serialize/src/SerializeAddon.ts
index dad6aa4f..ba366c37 100644
--- a/addons/xterm-addon-serialize/src/SerializeAddon.ts
+++ b/addons/xterm-addon-serialize/src/SerializeAddon.ts
@@ -11,6 +11,11 @@ function constrain(value: number, low: number, high: number): number {
   return Math.max(low, Math.min(value, high));
 }
 
+interface ISerializeOptions {
+  withAlternate?: boolean;
+
+}
+
 // TODO: Refine this template class later
 abstract class BaseSerializeHandler {
   constructor(private _buffer: IBuffer) { }
@@ -167,7 +172,7 @@ export class SerializeAddon implements ITerminalAddon {
     this._terminal = terminal;
   }
 
-  public serialize(rows?: number): string {
+  public serialize(rows?: number, options: ISerializeOptions = {}): string {
     // TODO: Add re-position cursor support
     // TODO: Add word wrap mode support
     // TODO: Add combinedData support
@@ -175,12 +180,25 @@ export class SerializeAddon implements ITerminalAddon {
       throw new Error('Cannot use addon until it has been loaded');
     }
 
-    const maxRows = this._terminal.buffer.active.length;
-    const handler = new StringSerializeHandler(this._terminal.buffer.active);
+    if (this._terminal.buffer.active.type === 'normal' || !(options?.withAlternate ?? false)) {
+      const maxRows = this._terminal.buffer.active.length;
+      const handler = new StringSerializeHandler(this._terminal.buffer.active);
 
-    rows = (rows === undefined) ? maxRows : constrain(rows, 0, maxRows);
+      rows = (rows === undefined) ? maxRows : constrain(rows, 0, maxRows);
 
-    return handler.serialize(maxRows - rows, maxRows);
+      return handler.serialize(maxRows - rows, maxRows);
+    }
+
+    const maxNormalRows = this._terminal.buffer.normal.length;
+    const maxAltRows = this._terminal.buffer.alternate.length;
+    const normalHandler = new StringSerializeHandler(this._terminal.buffer.normal);
+    const altHandler = new StringSerializeHandler(this._terminal.buffer.alternate);
+    const normalRows = (rows === undefined) ? maxNormalRows : constrain(rows, 0, maxNormalRows);
+    const altRows = (rows === undefined) ? maxAltRows : constrain(rows, 0, maxAltRows);
+
+    return normalHandler.serialize(maxNormalRows - normalRows, maxNormalRows)
+      + '\u001b[?1049h\u001b[H'
+      + altHandler.serialize(maxAltRows - altRows, maxAltRows);
   }
 
   public dispose(): void { }
diff --git a/addons/xterm-addon-serialize/test/SerializeAddon.api.ts b/addons/xterm-addon-serialize/test/SerializeAddon.api.ts
index 5b615db1..32e816a1 100644
--- a/addons/xterm-addon-serialize/test/SerializeAddon.api.ts
+++ b/addons/xterm-addon-serialize/test/SerializeAddon.api.ts
@@ -299,6 +299,38 @@ describe('SerializeAddon', () => {
     await writeSync(page, lines.join('\\r\\n'));
     assert.equal(await page.evaluate(`serializeAddon.serialize();`), expected.join('\r\n'));
   });
+
+  it('serialize with alt screen correctly', async () => {
+    const SMCUP = '\u001b[?1049h';
+    const CUP = '\u001b[H';
+
+    const lines = [
+      `1${SMCUP}${CUP}2`
+    ];
+    const expected = [
+      `1${SMCUP}${CUP}2`
+    ];
+
+    await writeSync(page, lines.join('\\r\\n'));
+    assert.equal(JSON.stringify(await page.evaluate(`window.term.buffer.active.type`)), '"alternate"');
+    assert.equal(JSON.stringify(await page.evaluate(`serializeAddon.serialize(undefined, { withAlternate: true });`)), JSON.stringify(expected.join('\r\n')));
+  });
+
+  it('serialize without alt screen correctly', async () => {
+    const SMCUP = '\u001b[?1049h';
+    const RMCUP = '\u001b[?1049l';
+
+    const lines = [
+      `1${SMCUP}2${RMCUP}`
+    ];
+    const expected = [
+      `1`
+    ];
+
+    await writeSync(page, lines.join('\\r\\n'));
+    assert.equal(JSON.stringify(await page.evaluate(`window.term.buffer.active === window.term.buffer.alt`)), 'false');
+    assert.equal(JSON.stringify(await page.evaluate(`serializeAddon.serialize(undefined, { withAlternate: true });`)), JSON.stringify(expected.join('\r\n')));
+  });
 });
 
 function newArray<T>(initial: T | ((index: number) => T), count: number): T[] {