Support opds (#133)

* Add OPDS catalog support for book discovery and downloading

* Implement OPDS search, improved book discovery, and enhanced UI details.

* Improve OPDS search and catalog management

* Add authentication support and extended metadata to the OPDS reader.

* Add support for OPDS 2.0 (JSON) feeds

* Enhance OPDS book downloading with progress tracking and multi-format support.

* Enhance OPDS book management and UI

* Add support for OPDS-PSE (Page Streaming Extension) streaming

* Improve OPDS streaming and catalog management

app/src/main/java/com/aryan/reader/opds/OpdsModels.kt

@@ -0,0 +1,93 @@
+// OpdsModels.kt
+package com.aryan.reader.opds
+
+data class OpdsCatalog(
+    val id: String,
+    val title: String,
+    val url: String,
+    val isDefault: Boolean = false,
+    val username: String? = null,
+    val password: String? = null
+)
+
+data class OpdsFacet(
+    val title: String,
+    val group: String,
+    val url: String,
+    val isActive: Boolean
+)
+
+data class OpdsFeed(
+    val title: String,
+    val entries: List<OpdsEntry>,
+    val nextUrl: String?,
+    val searchUrl: String? = null,
+    val facets: List<OpdsFacet> = emptyList()
+)
+
+data class OpdsAuthor(
+    val name: String,
+    val url: String?
+)
+
+data class OpdsAcquisition(
+    val url: String,
+    val mimeType: String
+) {
+    val formatName: String
+        get() = when {
+            mimeType.contains("epub") -> "EPUB"
+            mimeType.contains("pdf") -> "PDF"
+            mimeType.contains("mobi") || mimeType.contains("x-mobipocket-ebook") -> "MOBI"
+            mimeType.contains("fictionbook") || mimeType.contains("fb2") -> "FB2"
+            mimeType.contains("cbz") || mimeType.contains("comicbook") -> "CBZ"
+            mimeType.contains("cbr") || mimeType.contains("rar") -> "CBR"
+            mimeType.contains("txt") || mimeType.contains("text/plain") -> "TXT"
+            else -> mimeType.substringAfterLast("/").uppercase()
+        }
+
+    val priority: Int
+        get() = when (formatName) {
+            "EPUB" -> 5
+            "PDF" -> 4
+            "MOBI" -> 3
+            "FB2" -> 2
+            "CBZ" -> 1
+            "TXT" -> 0
+            else -> -1
+        }
+}
+
+data class OpdsEntry(
+    val id: String,
+    val title: String,
+    val summary: String?,
+    val authors: List<OpdsAuthor> = emptyList(),
+    val coverUrl: String?,
+    val acquisitions: List<OpdsAcquisition> = emptyList(),
+    val navigationUrl: String?,
+    val publisher: String? = null,
+    val published: String? = null,
+    val language: String? = null,
+    val series: String? = null,
+    val seriesIndex: String? = null,
+    val categories: List<String> = emptyList(),
+    // ADD THESE:
+    val pseCount: Int? = null,
+    val pseUrlTemplate: String? = null
+) {
+    val author: String?
+        get() = authors.firstOrNull()?.name
+
+    val bestAcquisition: OpdsAcquisition?
+        get() = acquisitions.maxByOrNull { it.priority }
+
+    val isAcquisition: Boolean
+        get() = acquisitions.isNotEmpty()
+
+    val isNavigation: Boolean
+        get() = navigationUrl != null && acquisitions.isEmpty()
+
+    val isStreamable: Boolean
+        get() = pseUrlTemplate != null && pseCount != null && pseCount > 0
+}