From 40a689688971f1587960e3bb70bcb2d9021c1e3c Mon Sep 17 00:00:00 2001
From: Peter Tang <petersktang@gmail.com>
Date: Fri, 15 Sep 2023 17:06:06 +0800
Subject: [PATCH] corrected some variable names within BundleManager functions,
 added onDemandBundle registration instead of loading all Resources at
 startup.

---
 Sources/SwiftMath/MathBundle/MathFont.swift | 27 +++++++++++++++------
 Tests/SwiftMathTests/MathFontTests.swift    |  7 ++++++
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/Sources/SwiftMath/MathBundle/MathFont.swift b/Sources/SwiftMath/MathBundle/MathFont.swift
index 5be5d50..4c8a1b6 100644
--- a/Sources/SwiftMath/MathBundle/MathFont.swift
+++ b/Sources/SwiftMath/MathBundle/MathFont.swift
@@ -126,16 +126,28 @@ private class BundleManager {
         initializedOnceAlready.toggle()
     }
     
+    private func onDemandRegistration(mathFont: MathFont) {
+        guard cgFonts[mathFont] == nil else { return }
+        do {
+            try BundleManager.manager.registerCGFont(mathFont: mathFont)
+            try BundleManager.manager.registerMathTable(mathFont: mathFont)
+
+        } catch {
+            fatalError("MTMathFonts:\(#function) ondemand loading failed, mathFont \(mathFont.rawValue), reason \(error)")
+        }
+    }
     fileprivate func obtainCGFont(font: MathFont) -> CGFont {
-        if !initializedOnceAlready { registerAllBundleResources() }
-        guard let cfFont = cgFonts[font] else {
-            fatalError("\(#function) unable to locate CTFont \(font.fontName)")
+        // if !initializedOnceAlready { registerAllBundleResources() }
+        onDemandRegistration(mathFont: font)
+        guard let cgFont = cgFonts[font] else {
+            fatalError("\(#function) unable to locate CGFont \(font.fontName)")
         }
-        return cfFont
+        return cgFont
     }
     
     fileprivate func obtainCTFont(font: MathFont, withSize size: CGFloat) -> CTFont {
-        if !initializedOnceAlready { registerAllBundleResources() }
+        // if !initializedOnceAlready { registerAllBundleResources() }
+        onDemandRegistration(mathFont: font)
         let fontPair = CTFontPair(font: font, size: size)
         guard let ctFont = ctFonts[fontPair] else {
             if let cgFont = cgFonts[font] {
@@ -143,12 +155,13 @@ private class BundleManager {
                 ctFonts[fontPair] = ctFont
                 return ctFont
             }
-            fatalError("\(#function) unable to locate CTFont \(font.fontName)")
+            fatalError("\(#function) unable to locate CGFont \(font.fontName), nor create CTFont")
         }
         return ctFont
     }
     fileprivate func obtainMathTable(font: MathFont) -> NSDictionary {
-        if !initializedOnceAlready { registerAllBundleResources() }
+        // if !initializedOnceAlready { registerAllBundleResources() }
+        onDemandRegistration(mathFont: font)
         guard let mathTable = mathTables[font] else {
             fatalError("\(#function) unable to locate mathTable: \(font.rawValue).plist")
         }
diff --git a/Tests/SwiftMathTests/MathFontTests.swift b/Tests/SwiftMathTests/MathFontTests.swift
index 09ac0db..ed2f441 100644
--- a/Tests/SwiftMathTests/MathFontTests.swift
+++ b/Tests/SwiftMathTests/MathFontTests.swift
@@ -37,6 +37,13 @@ final class MathFontTests: XCTestCase {
         }
         #endif
     }
+    func testOnDemandMathFontScript() throws {
+        let size = Int.random(in: 20 ... 40)
+        let mathFont = MathFont.allCases.randomElement()!
+        XCTAssertNotNil(mathFont.cgFont())
+        XCTAssertNotNil(mathFont.ctFont(withSize: CGFloat(size)))
+        XCTAssertEqual(mathFont.ctFont(withSize: CGFloat(size)).fontSize, CGFloat(size), "ctFont fontSize test")
+    }
     var fontNames: [String] {
         MathFont.allCases.map { $0.fontName }
     }