commit 6b875fc2bf1f261be41b68dfd9d7f94aa941710b
Author: bsncubed <ben@apointless.space>
Date:   Sat Mar 30 16:01:47 2024 +1100

    File Added

diff --git a/book-to-static.php b/book-to-static.php
new file mode 100644
index 0000000..c72df43
--- /dev/null
+++ b/book-to-static.php
@@ -0,0 +1,263 @@
+#!/usr/bin/env php
+<?php
+
+// API Credentials
+// You can either provide them as environment variables
+// or hard-code them in the empty strings below.
+$apiUrl = getenv('BS_URL') ?: '';
+$clientId = getenv('BS_TOKEN_ID') ?: '';
+$clientSecret = getenv('BS_TOKEN_SECRET') ?: '';
+
+// Output Folder
+// Can be provided as a arguments when calling the script
+// or be hard-coded as strings below.
+$bookSlug = $argv[1] ?? '';
+$outFolder = $argv[2] ?? './out';
+
+// Script logic
+////////////////
+
+// Check we have required options
+if (empty($bookSlug) || empty($outFolder)) {
+    errorOut("Both a book slug and output folder must be provided");
+}
+
+// Create the output folder if it does not exist
+if (!is_dir($outFolder)) {
+    mkdir($outFolder, 0777, true);
+}
+
+// Get full output directory and book details
+$outDir = realpath($outFolder);
+$book = getBookBySlug($bookSlug);
+
+// Error out if we don't have a book
+if (is_null($book)) {
+    errorOut("Could not find book with the URL slug: {$bookSlug}");
+}
+
+// Get all chapters and pages within the book
+$chapters = getAllOfAtListEndpoint("api/chapters", ['filter[book_id]' => $book['id']]);
+$pages = getAllOfAtListEndpoint("api/pages", ['filter[book_id]' => $book['id']]);
+
+// Get the full content for each page
+foreach ($pages as $index => $page) {
+    $pages[$index] = apiGetJson("api/pages/{$page['id']}");
+}
+
+// Create the image output directory
+if (!is_dir($outDir . "/images")) {
+    mkdir($outDir . "/images", 0777, true);
+}
+
+// Find the pages that are not within a chapter
+$directBookPages = array_filter($pages, function($page) {
+    return empty($page['chapter_id']);
+});
+
+// Create book index file
+$bookIndex = getBookHtmlOutput($book, $chapters, $directBookPages);
+file_put_contents($outDir . "/index.html", $bookIndex);
+
+// Create a HTML file for each chapter
+// in addition to each page within those chapters
+foreach ($chapters as $chapter) {
+    $childPages = array_filter($pages, function($page) use ($chapter) {
+        return $page['chapter_id'] == $chapter['id'];
+    });
+    $chapterPage = getChapterHtmlOutput($chapter, $childPages);
+    file_put_contents($outDir . "/chapter-{$chapter['slug']}.html", $chapterPage);
+
+    foreach ($childPages as $childPage) {
+        $childPageContent = getPageHtmlOutput($childPage, $chapter);
+        $childPageContent = extractImagesFromHtml($childPageContent);
+        file_put_contents($outDir . "/page-{$childPage['slug']}.html", $childPageContent);
+    }
+}
+
+// Create a file for each direct child book page
+foreach ($directBookPages as $directPage) {
+    $directPageContent = getPageHtmlOutput($directPage, null);
+    $directPageContent = extractImagesFromHtml($directPageContent);
+    file_put_contents($outDir . "/page-{$directPage['slug']}.html", $directPageContent);
+}
+
+/**
+ * Scan the given HTML for image URL's and extract those images
+ * to save them locally and update the HTML references to point
+ * to the local files.
+ */
+function extractImagesFromHtml(string $html): string {
+    global $outDir;
+    static $savedImages = [];
+    $matches = [];
+    preg_match_all('/<img.*?src=["\'](.*?)[\'"].*?>/i', $html, $matches);
+    foreach (array_unique($matches[1] ?? []) as $url) {
+        $image = getImageFile($url);
+        if ($image === false) {
+            continue;
+        }
+
+        $name = basename($url);
+        $fileName = $name;
+        $count = 1;
+        while (isset($savedImages[$fileName])) {
+            $fileName = $count . '-' . $name;
+            $count++;
+        }
+
+        $savedImages[$fileName] = true;
+        file_put_contents($outDir . "/images/" . $fileName, $image);
+        $html = str_replace($url, "./images/" . $fileName, $html);
+    }
+    return $html;
+}
+
+/**
+ * Get an image file from the given URL.
+ * Checks if it's hosted on the same instance as the API we're
+ * using so that auth details can be provided for BookStack images
+ * in case local_secure images are in use.
+ */
+function getImageFile(string $url): string {
+    global $apiUrl;
+    if (strpos(strtolower($url), strtolower($apiUrl)) === 0) {
+        $url = substr($url, strlen($apiUrl));
+        return apiGet($url);
+    }
+    return @file_get_contents($url);
+}
+
+/**
+ * Get the HTML representation of a book.
+ */
+function getBookHtmlOutput(array $book, array $chapters, array $pages): string {
+    $content = "<html><link rel='stylesheet' href='markdown.css'><head></head><body>";
+    $content .= "<h1>{$book['name']}</h1>";
+    $content .= "<p>{$book['description']}</p>";
+    $content .= "<hr>";
+    if (count($chapters) > 0) {
+        $content .= "<h3>Chapters</h3><ul>";
+        foreach ($chapters as $chapter) {
+            $content .= "<li><a href='./chapter-{$chapter['slug']}.html'>{$chapter['name']}</a></li>";
+        }
+        $content .= "</ul>";
+    }
+    if (count($pages) > 0) {
+        $content .= "<h3>Pages</h3><ul>";
+        foreach ($pages as $page) {
+            $content .= "<li><a href='./page-{$page['slug']}.html'>{$page['name']}</a></li>";
+        }
+        $content .= "</ul>";
+    }
+    return $content;
+}
+
+/**
+ * Get the HTML representation of a chapter.
+ */
+function getChapterHtmlOutput(array $chapter, array $pages): string {
+    $content = "<html><link rel='stylesheet' href='markdown.css'><head></head><body>";
+    $content .= "<p><a href='./index.html'>Back to book</a></p>";
+    $content .= "<h1>{$chapter['name']}</h1>";
+    $content .= "<p>{$chapter['description']}</p>";
+    $content .= "<hr>";
+    if (count($pages) > 0) {
+        $content .= "<h3>Pages</h3><ul>";
+        foreach ($pages as $page) {
+            $content .= "<li><a href='./page-{$page['slug']}.html'>{$page['name']}</a></li>";
+        }
+        $content .= "</ul>";
+    }
+    return $content;
+}
+
+/**
+ * Get the HTML representation of a page.
+ */
+function getPageHtmlOutput(array $page, ?array $parentChapter): string {
+    $content = "<html><link rel='stylesheet' href='markdown.css'><head></head><body>";
+    if (is_null($parentChapter)) {
+        $content .= "<p><a href='./index.html'>Back to book</a></p>";
+    } else {
+        $content .= "<p><a href='./chapter-{$parentChapter['slug']}.html'>Back to chapter</a></p>";
+    }
+    $content .= "<h1>{$page['name']}</h1>";
+    $content .= "<div>{$page['html']}</div>";
+
+    return $content;
+}
+
+/**
+ * Get a single book by the slug or return null if not exists.
+ */
+function getBookBySlug(string $slug): ?array {
+    $endpoint = 'api/books?' . http_build_query(['filter[slug]' => $slug]);
+    $resp = apiGetJson($endpoint);
+    $book = $resp['data'][0] ?? null;
+
+    if (!is_null($book)) {
+        $book = apiGetJson("api/books/{$book['id']}") ?? null;
+    }
+    return $book;
+}
+
+/**
+ * Get all books from the system API.
+ */
+function getAllOfAtListEndpoint(string $endpoint, array $params): array {
+    $count = 100;
+    $offset = 0;
+    $total = 0;
+    $all = [];
+
+    do {
+        $endpoint = $endpoint . '?' . http_build_query(array_merge($params, ['count' => $count, 'offset' => $offset]));
+        $resp = apiGetJson($endpoint);
+
+        $total = $resp['total'] ?? 0;
+        $new = $resp['data'] ?? [];
+        array_push($all, ...$new);
+        $offset += $count;
+    } while ($offset < $total);
+
+    return $all;
+}
+
+/**
+ * Make a simple GET HTTP request to the API.
+ */
+function apiGet(string $endpoint): string {
+    global $apiUrl, $clientId, $clientSecret;
+    $url = rtrim($apiUrl, '/') . '/' . ltrim($endpoint, '/');
+    $opts = ['http' => ['header' => "Authorization: Token {$clientId}:{$clientSecret}"]];
+    $context = stream_context_create($opts);
+    return @file_get_contents($url, false, $context);
+}
+
+/**
+ * Make a simple GET HTTP request to the API &
+ * decode the JSON response to an array.
+ */
+function apiGetJson(string $endpoint): array {
+    $data = apiGet($endpoint);
+    return json_decode($data, true);
+}
+
+/**
+ * DEBUG: Dump out the given variables and exit.
+ */
+function dd(...$args) {
+    foreach ($args as $arg) {
+        var_dump($arg);
+    }
+    exit(1);
+}
+
+/**
+ * Alert of an error then exit the script.
+ */
+function errorOut(string $text) {
+    echo "ERROR: " .  $text;
+    exit(1);
+}
\ No newline at end of file