Moving OpenGraph parser to commons

2026-01-07 16:34:15 -05:00
parent cba4d25424
commit 882cf6ee59
8 changed files with 77 additions and 44 deletions
@@ -0,0 +1,56 @@
+/**
+ * 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.amethyst.commons.preview
+
+import java.nio.charset.Charset
+
+object HtmlCharsetParser {
+    val ATTRIBUTE_VALUE_CHARSET = "charset"
+    val ATTRIBUTE_VALUE_HTTP_EQUIV = "http-equiv"
+    val CONTENT = "content"
+
+    private val RE_CONTENT_TYPE_CHARSET = Regex("""charset=([^;]+)""")
+
+    fun detectCharset(bodyBytes: ByteArray): Charset {
+        // try to detect charset from meta tags parsed from first 1024 bytes of body
+        val firstPart = String(bodyBytes, 0, 1024, Charset.forName("utf-8"))
+        val metaTags = MetaTagsParser.parse(firstPart)
+        metaTags.forEach { meta ->
+            val charsetAttr = meta.attr(ATTRIBUTE_VALUE_CHARSET)
+            if (charsetAttr.isNotEmpty()) {
+                runCatching { Charset.forName(charsetAttr) }.getOrNull()?.let {
+                    return it
+                }
+            }
+            if (meta.attr(ATTRIBUTE_VALUE_HTTP_EQUIV).lowercase() == "content-type") {
+                RE_CONTENT_TYPE_CHARSET
+                    .find(meta.attr(CONTENT))
+                    ?.let {
+                        runCatching { Charset.forName(it.groupValues[1]) }.getOrNull()
+                    }?.let {
+                        return it
+                    }
+            }
+        }
+        // defaults to UTF-8
+        return Charset.forName("utf-8")
+    }
+}
@@ -0,0 +1,125 @@
+/**
+ * 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.amethyst.commons.preview
+
+class OpenGraphParser {
+    class Result(
+        val title: String,
+        val description: String,
+        val image: String,
+    )
+
+    companion object {
+        val ATTRIBUTE_VALUE_PROPERTY = "property"
+        val ATTRIBUTE_VALUE_NAME = "name"
+        val ATTRIBUTE_VALUE_ITEMPROP = "itemprop"
+
+        // for <meta itemprop=... to get title
+        private val META_X_TITLE =
+            arrayOf(
+                "og:title",
+                "twitter:title",
+                "title",
+            )
+
+        // for <meta itemprop=... to get description
+        private val META_X_DESCRIPTION =
+            arrayOf(
+                "og:description",
+                "twitter:description",
+                "description",
+            )
+
+        // for <meta itemprop=... to get image
+        private val META_X_IMAGE =
+            arrayOf(
+                "og:image",
+                "twitter:image",
+                "image",
+            )
+
+        private val CONTENT = "content"
+    }
+
+    fun extractUrlInfo(metaTags: Sequence<MetaTag>): Result {
+        var title: String = ""
+        var description: String = ""
+        var image: String = ""
+
+        metaTags.forEach {
+            when (it.attr(ATTRIBUTE_VALUE_PROPERTY)) {
+                in META_X_TITLE ->
+                    if (title.isEmpty()) {
+                        title = it.attr(CONTENT)
+                    }
+
+                in META_X_DESCRIPTION ->
+                    if (description.isEmpty()) {
+                        description = it.attr(CONTENT)
+                    }
+
+                in META_X_IMAGE ->
+                    if (image.isEmpty()) {
+                        image = it.attr(CONTENT)
+                    }
+            }
+
+            when (it.attr(ATTRIBUTE_VALUE_NAME)) {
+                in META_X_TITLE ->
+                    if (title.isEmpty()) {
+                        title = it.attr(CONTENT)
+                    }
+
+                in META_X_DESCRIPTION ->
+                    if (description.isEmpty()) {
+                        description = it.attr(CONTENT)
+                    }
+
+                in META_X_IMAGE ->
+                    if (image.isEmpty()) {
+                        image = it.attr(CONTENT)
+                    }
+            }
+
+            when (it.attr(ATTRIBUTE_VALUE_ITEMPROP)) {
+                in META_X_TITLE ->
+                    if (title.isEmpty()) {
+                        title = it.attr(CONTENT)
+                    }
+
+                in META_X_DESCRIPTION ->
+                    if (description.isEmpty()) {
+                        description = it.attr(CONTENT)
+                    }
+
+                in META_X_IMAGE ->
+                    if (image.isEmpty()) {
+                        image = it.attr(CONTENT)
+                    }
+            }
+
+            if (title.isNotEmpty() && description.isNotEmpty() && image.isNotEmpty()) {
+                return Result(title, description, image)
+            }
+        }
+        return Result(title, description, image)
+    }
+}
@@ -0,0 +1,45 @@
+/**
+ * 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.amethyst.commons.preview
+
+import androidx.compose.runtime.Immutable
+import java.net.URL
+
+@Immutable
+class UrlInfoItem(
+    val url: String = "",
+    val title: String = "",
+    val description: String = "",
+    val image: String = "",
+    val mimeType: String,
+) {
+    val verifiedUrl = runCatching { URL(url) }.getOrNull()
+    val imageUrlFullPath =
+        if (image.startsWith("/")) {
+            URL(verifiedUrl, image).toString()
+        } else {
+            image
+        }
+
+    fun fetchComplete(): Boolean = url.isNotEmpty() && image.isNotEmpty()
+
+    fun allFetchComplete(): Boolean = title.isNotEmpty() && description.isNotEmpty() && image.isNotEmpty()
+}