manager: add monet colors support to webui (webui-next)

- colors are served to /internal/colors.css

the current vars are :

primary
onPrimary
background
onSurface
onSurfaceVariant
tonalSurface
surfaceBright
outlineVariant
error

manager/app/src/main/java/com/rifsxd/ksunext/ui/webui/MonetColorsProvider.kt

@@ -0,0 +1,55 @@
+package com.rifsxd.ksunext.ui.webui
+
+import android.content.Context
+import android.content.res.Configuration
+import android.os.Build
+
+import androidx.compose.material3.dynamicDarkColorScheme
+import androidx.compose.material3.dynamicLightColorScheme
+import androidx.compose.ui.graphics.toArgb
+
+/**
+ * @author rifsxd
+ * @date 2025/6/2.
+ */
+object MonetColorsProvider {
+    fun getColorsCss(context: Context): String {
+
+        // Detect dark mode
+        val isDark = (context.resources.configuration.uiMode and Configuration.UI_MODE_NIGHT_MASK) == Configuration.UI_MODE_NIGHT_YES
+
+        val colorScheme = if (isDark) {
+            dynamicDarkColorScheme(context)
+        } else {
+            dynamicLightColorScheme(context)
+        }
+
+        val monetColors = mapOf(
+            "primary" to colorScheme.primary.toArgb().toHex(),
+            "onPrimary" to colorScheme.onPrimary.toArgb().toHex(),
+            "background" to colorScheme.background.toArgb().toHex(),
+            "onSurface" to colorScheme.onSurface.toArgb().toHex(),
+            "onSurfaceVariant" to colorScheme.onSurfaceVariant.toArgb().toHex(),
+            "tonalSurface" to colorScheme.surface.toArgb().toHex(),
+            "surfaceBright" to colorScheme.surfaceVariant.toArgb().toHex(),
+            "outlineVariant" to colorScheme.outlineVariant.toArgb().toHex(),
+            "error" to colorScheme.error.toArgb().toHex()
+        )
+
+        return monetColors.toCssVars()
+    }
+
+    private fun Map<String, String>.toCssVars(): String {
+        return buildString {
+            append(":root {\n")
+            for ((k, v) in this@toCssVars) {
+                append("  --$k: $v;\n")
+            }
+            append("}\n")
+        }
+    }
+
+    private fun Int.toHex(): String {
+        return String.format("#%06X", 0xFFFFFF and this)
+    }
+}

manager/app/src/main/java/com/rifsxd/ksunext/ui/webui/SuFilePathHandler.java

@@ -1,6 +1,7 @@
 package com.rifsxd.ksunext.ui.webui;
 
 import android.content.Context;
+import android.os.Build;
 import android.util.Log;
 import android.webkit.WebResourceResponse;
 
@@ -15,8 +16,12 @@ import com.topjohnwu.superuser.io.SuFileInputStream;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.ByteArrayInputStream;
+import java.nio.charset.StandardCharsets;
 import java.util.zip.GZIPInputStream;
 
+import com.rifsxd.ksunext.ui.webui.MonetColorsProvider;
+
 /**
  * Handler class to open files from file system by root access
  * For more information about android storage please refer to
@@ -81,8 +86,11 @@ public final class SuFilePathHandler implements WebViewAssetLoader.PathHandler {
      *                  which files can be loaded.
      * @throws IllegalArgumentException if the directory is not allowed.
      */
+    private final Context mContext;
+
     public SuFilePathHandler(@NonNull Context context, @NonNull File directory, Shell rootShell) {
         try {
+            mContext = context;
             mDirectory = new File(getCanonicalDirPath(directory));
             if (!isAllowedInternalStorageDir(context)) {
                 throw new IllegalArgumentException("The given directory \"" + directory
@@ -130,6 +138,16 @@ public final class SuFilePathHandler implements WebViewAssetLoader.PathHandler {
     @WorkerThread
     @NonNull
     public WebResourceResponse handle(@NonNull String path) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+            if ("internal/colors.css".equals(path)) {
+                String css = MonetColorsProvider.INSTANCE.getColorsCss(mContext);
+                return new WebResourceResponse(
+                        "text/css",
+                        "utf-8",
+                        new ByteArrayInputStream(css.getBytes(StandardCharsets.UTF_8))
+                );
+            }
+        }
         try {
             File file = getCanonicalFileIfChild(mDirectory, path);
             if (file != null) {