From 87b011191514af3730a78142f59a0b4eb6e13f39 Mon Sep 17 00:00:00 2001
From: Thomas Forgione <thomas@forgione.fr>
Date: Wed, 1 Mar 2023 18:16:17 +0100
Subject: [PATCH] Work on multiple slides

---
 index.js | 127 +++++++++++++++++++++++++++++++++----------------------
 1 file changed, 76 insertions(+), 51 deletions(-)

diff --git a/index.js b/index.js
index a7c7def..a611d38 100644
--- a/index.js
+++ b/index.js
@@ -231,65 +231,90 @@ async function main() {
     await page.setViewport(size);
     await page.goto('file://' + path);
 
-    // Only consider the first slide (#\\331 === #1, which is the id of the first slide)
-    // We don't take into account the other slides because it will mess up with our screenshot varification
-    let root = await page.$('#\\31');
+    let output = [];
 
-    // If there is no slide, try to run on HTML body
-    if (root === null) {
-        error('not a marp HTML file');
-        process.exit(1);
-    }
+    for (let pageIndex = 1;; pageIndex++) {
 
-    // Hide slides controls
-    await page.evaluate(() => {
-        for (let elt of document.getElementsByClassName('bespoke-marp-osc')) {
-            elt.style.visibility = "hidden";
+        let root = await page.$('#\\3' + pageIndex);
+        if (root === null) {
+            break;
         }
-    });
 
-    // Take a first screenshot
-    await page.screenshot({path: (outputDir === null ? __dirname : outputDir) + '/' + 'screenshot1.png'});
+        info("analysing slide " + pageIndex);
+
+        // Hide slides controls
+        await page.evaluate(() => {
+            for (let elt of document.getElementsByClassName('bespoke-marp-osc')) {
+                elt.style.visibility = "hidden";
+            }
+        });
+
+        // Take a first screenshot
+        await page.screenshot({path: (outputDir === null ? __dirname : outputDir) + '/' + 'screenshot1.png'});
+
+        // Edit the page to shrink elements in order to get better bounding boxes
+        if (shrinkBoxes) {
+            info("shrinking bounding boxes");
+            await addSpan(root);
+            info("boundingboxes shrunk");
+            eprintln();
+        }
+
+        // Take another screenshot and check the modification we made didn't change the layout of the page
+        await page.screenshot({path: (outputDir === null ? __dirname : outputDir) + '/' + 'screenshot2.png'});
+
+        // Compare both screenshots
+        let file1 = await fs.readFile(__dirname + '/' + 'screenshot1.png');
+        let file2 = await fs.readFile(__dirname + '/' + 'screenshot2.png');
+        let filesAreSame = file1.map((x, i) => x === file2[i]).reduce((a, b) => a && b, true);
+
+        if (!filesAreSame) {
+            // Check psnr
+            let psnr = await image.psnr(__dirname + '/' + 'screenshot1.png', __dirname + '/' + 'screenshot2.png');
+
+            // Crash if they're different
+            if (psnr > 70) {
+                warning(filename + " produced slight diff: psnr = " + psnr);
+            } else {
+                await error("page edit changed the layout: psnr = " + psnr);
+                process.exit(1);
+            }
+        }
+
+        // Analyse the root and output the result
+        info("performing analysis");
+        let analyse = await analyseElement(root, page, outputDir, threshold);
+        info("analysis done");
+
+        // Append the current slide to the output
+        if (flatten) {
+
+            analyse = flattenTree(analyse);
+            for (let elt of anaylse) {
+                output.push(elt);
+            }
+
+        } else {
+
+            output.push(analyse);
+
+        }
+
+        // Go to the next page
+        await page.evaluate(el => {
+            let buttons = document.getElementsByTagName('button');
+            for (let button of buttons) {
+                if (button.title === "Next slide") {
+                    button.click();
+                }
+            }
+        });
 
-    // Edit the page to shrink elements in order to get better bounding boxes
-    if (shrinkBoxes) {
-        info("shrinking bounding boxes");
-        await addSpan(root);
-        info("boundingboxes shrunk");
         eprintln();
     }
 
-    // Take another screenshot and check the modification we made didn't change the layout of the page
-    await page.screenshot({path: (outputDir === null ? __dirname : outputDir) + '/' + 'screenshot2.png'});
-
-    // Compare both screenshots
-    let file1 = await fs.readFile(__dirname + '/' + 'screenshot1.png');
-    let file2 = await fs.readFile(__dirname + '/' + 'screenshot2.png');
-    let filesAreSame = file1.map((x, i) => x === file2[i]).reduce((a, b) => a && b, true);
-
-    if (!filesAreSame) {
-        // Check psnr
-        let psnr = await image.psnr(__dirname + '/' + 'screenshot1.png', __dirname + '/' + 'screenshot2.png');
-
-        // Crash if they're different
-        if (psnr > 70) {
-            warning(filename + " produced slight diff: psnr = " + psnr);
-        } else {
-            await error("page edit changed the layout: psnr = " + psnr);
-            process.exit(1);
-        }
-    }
-
-    // Analyse the root and output the result
-    info("performing analysis");
-    let analyse = await analyseElement(root, page, outputDir, threshold);
-    info("analysis done");
-
-    if (flatten) {
-        analyse = flattenTree(analyse);
-    }
-
-    let json = JSON.stringify(analyse, undefined, 4);
+    info("saving output");
+    let json = JSON.stringify(output, undefined, 4);
     if (outputDir === null) {
         console.log(json);
     } else {