feat(audio-rooms): font-tag parser + system-font typography (T3 #1)

Closes the deferred font tag from the Tier-3 plan. Wire-up: * quartz: FontTag(family, optionalUrl) parser/assembler with blank-rejection on family + blank-URL-becomes-null normalisation. * MeetingSpaceEvent.font(): FontTag? accessor. * TagArrayBuilder.font(family, url) DSL. * RoomTheme gains fontFamily / fontUrl fields. * AudioRoomThemedScope maps `family` to a Compose FontFamily for the four CSS-style generic-family names ("sans-serif", "serif", "monospace", "cursive") — each maps to the corresponding system fallback. The whole Material3 typography is rebuilt with that family so headlines / body / labels all swap together. URL-based font loading (RoomTheme.fontUrl) is the natural follow-up: fetch + cache via OkHttp, then build a FontFamily from a local file. Until then, an unknown family is silently a no-op — the room renders in the platform default rather than crashing or fetching on the UI thread. Tests: * FontTagTest — 9 cases covering family-only, family+URL, blank rejection, missing family, wrong tag name, blank-URL normalisation, assembler shapes (with + without URL), and the assembler's blank-family rejection. * RoomThemeTest gains 3 cases for font projection (family-only / family+URL / empty event).
2026-04-26 23:55:49 +00:00
parent bed9a2ee21
commit 14863415d5
7 changed files with 284 additions and 2 deletions
@@ -85,6 +85,14 @@ class MeetingSpaceEvent(
     */
    fun background() = tags.firstNotNullOfOrNull(com.vitorpamplona.quartz.nip53LiveActivities.meetingSpaces.tags.BackgroundTag::parse)

+    /**
+     * Suggested typography for the room screen. Returns the first
+     * `["f", family, optionalUrl]` tag. Clients with theming
+     * support match the family against system fonts (or fetch the
+     * URL); clients without theming support ignore.
+     */
+    fun font() = tags.firstNotNullOfOrNull(com.vitorpamplona.quartz.nip53LiveActivities.meetingSpaces.tags.FontTag::parse)
+
    /**
     * Scheduled start time as unix seconds, only meaningful when
     * [status] is [StatusTag.STATUS.PLANNED]. Returns null on
@@ -53,6 +53,14 @@ fun TagArrayBuilder<MeetingSpaceEvent>.starts(unixSeconds: Long) =
            .assemble(unixSeconds),
    )

+fun TagArrayBuilder<MeetingSpaceEvent>.font(
+    family: String,
+    url: String? = null,
+) = addUnique(
+    com.vitorpamplona.quartz.nip53LiveActivities.meetingSpaces.tags.FontTag
+        .assemble(family, url),
+)
+
 fun TagArrayBuilder<MeetingSpaceEvent>.relays(urls: List<NormalizedRelayUrl>) = addUnique(RelayListTag.assemble(urls))

 fun TagArrayBuilder<MeetingSpaceEvent>.participant(
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip53LiveActivities.meetingSpaces.tags
+
+import com.vitorpamplona.quartz.nip01Core.core.has
+import com.vitorpamplona.quartz.utils.ensure
+
+/**
+ * `["f", family, optionalUrl]` on a kind-30312 audio-room event.
+ * The host suggests a font family for the room screen; clients
+ * with theming support load it (URL → fetch font file; bare
+ * family → match against a built-in / system font name with the
+ * client's platform fallback). Clients without theming support
+ * ignore the tag.
+ *
+ * The URL component is optional and is the only spec-defined way
+ * to request a non-system font (e.g. a Google-Fonts WOFF). When
+ * present, the URL must be HTTPS — the parser does not enforce
+ * this (a renderer is free to decline `http://` for security
+ * reasons), but invalid / blank family values are rejected so
+ * the renderer can trust the parsed shape.
+ */
+class FontTag(
+    val family: String,
+    val url: String?,
+) {
+    companion object {
+        const val TAG_NAME = "f"
+
+        fun parse(tag: Array<String>): FontTag? {
+            ensure(tag.has(1)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            val family = tag[1]
+            ensure(family.isNotBlank()) { return null }
+            val url = tag.getOrNull(2)?.takeIf { it.isNotBlank() }
+            return FontTag(family, url)
+        }
+
+        fun assemble(
+            family: String,
+            url: String? = null,
+        ): Array<String> {
+            require(family.isNotBlank()) { "font: family must not be blank" }
+            return if (url != null) arrayOf(TAG_NAME, family, url) else arrayOf(TAG_NAME, family)
+        }
+    }
+}
@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip53LiveActivities.meetingSpaces.tags
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
+import kotlin.test.assertNotNull
+import kotlin.test.assertNull
+
+class FontTagTest {
+    @Test
+    fun parsesFamilyOnly() {
+        val parsed = FontTag.parse(arrayOf("f", "Inter"))
+        assertNotNull(parsed)
+        assertEquals("Inter", parsed.family)
+        assertNull(parsed.url)
+    }
+
+    @Test
+    fun parsesFamilyWithUrl() {
+        val parsed = FontTag.parse(arrayOf("f", "Inter", "https://fonts.example/inter.woff2"))
+        assertNotNull(parsed)
+        assertEquals("Inter", parsed.family)
+        assertEquals("https://fonts.example/inter.woff2", parsed.url)
+    }
+
+    @Test
+    fun rejectsBlankFamily() {
+        // A blank family is not actionable for the renderer — match
+        // ColorTag's strictness rather than letting an empty value
+        // through and surprising the typography fallback.
+        assertNull(FontTag.parse(arrayOf("f", "")))
+        assertNull(FontTag.parse(arrayOf("f", "  ")))
+    }
+
+    @Test
+    fun rejectsMissingFamily() {
+        assertNull(FontTag.parse(arrayOf("f")))
+    }
+
+    @Test
+    fun rejectsWrongName() {
+        assertNull(FontTag.parse(arrayOf("font", "Inter")))
+    }
+
+    @Test
+    fun blankUrlBecomesNull() {
+        // A blank third element is treated as "no URL" rather than
+        // an empty URL — otherwise the renderer would attempt an
+        // HTTP fetch for "" and fail at the URL parser.
+        val parsed = FontTag.parse(arrayOf("f", "Inter", ""))
+        assertNotNull(parsed)
+        assertNull(parsed.url)
+    }
+
+    @Test
+    fun assembleFamilyOnly() {
+        assertEquals(
+            arrayOf("f", "Inter").toList(),
+            FontTag.assemble("Inter").toList(),
+        )
+    }
+
+    @Test
+    fun assembleWithUrl() {
+        assertEquals(
+            arrayOf("f", "Inter", "https://fonts.example/inter.woff2").toList(),
+            FontTag.assemble("Inter", "https://fonts.example/inter.woff2").toList(),
+        )
+    }
+
+    @Test
+    fun assembleRejectsBlankFamily() {
+        assertFailsWith<IllegalArgumentException> { FontTag.assemble("") }
+    }
+}