Initial commit

app/src/main/java/com/aryan/reader/epubreader/EpubReaderVertical.kt

@@ -0,0 +1,121 @@
+package com.aryan.reader.epubreader
+
+import timber.log.Timber
+import android.webkit.JavascriptInterface
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.automirrored.filled.ArrowForward
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import org.json.JSONObject
+import kotlin.math.min
+
+val DRAG_TO_CHANGE_CHAPTER_THRESHOLD_DP = 100.dp
+val PAGE_INFO_BAR_HEIGHT = 25.dp
+
+@Composable
+fun ChapterChangeIndicator(
+    text: String,
+    progress: Float,
+    isPullingDown: Boolean,
+    modifier: Modifier = Modifier
+) {
+    val alpha = min(1f, progress * 1.5f)
+    if (alpha > 0.1f) {
+        Surface(
+            modifier = modifier
+                .fillMaxWidth()
+                .alpha(alpha)
+                .padding(horizontal = 16.dp),
+            shape = MaterialTheme.shapes.medium,
+            color = MaterialTheme.colorScheme.inverseSurface.copy(alpha = 0.5f),
+            tonalElevation = 4.dp
+        ) {
+            Column(
+                modifier = Modifier.padding(vertical = 8.dp),
+                horizontalAlignment = Alignment.CenterHorizontally
+            ) {
+                Icon(
+                    imageVector = if (isPullingDown) Icons.AutoMirrored.Filled.ArrowBack else Icons.AutoMirrored.Filled.ArrowForward,
+                    contentDescription = null,
+                    tint = MaterialTheme.colorScheme.inverseOnSurface,
+                    modifier = Modifier.size(20.dp * min(1f, progress + 0.2f))
+                )
+                Spacer(modifier = Modifier.height(4.dp))
+                Text(
+                    text = if (progress >= 1.0f) text else "Pull further... (${(progress * 100).toInt()}%)",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.inverseOnSurface,
+                    textAlign = TextAlign.Center
+                )
+            }
+        }
+    }
+}
+
+enum class ChapterScrollPosition {
+    START, END
+}
+
+data class SelectionRect(
+    val x: Float,
+    val y: Float,
+    val width: Float,
+    val height: Float,
+    val text: String
+)
+
+interface TextSelectionListener {
+    fun onTextSelected(rect: SelectionRect)
+    fun onSelectionCleared()
+}
+
+@Suppress("unused")
+class TextSelectionJsInterface(private val listener: TextSelectionListener) {
+    @JavascriptInterface
+    fun onTextSelected(rectJson: String) {
+        try {
+            val json = JSONObject(rectJson)
+            val rect = SelectionRect(
+                x = json.getDouble("x").toFloat(),
+                y = json.getDouble("y").toFloat(),
+                width = json.getDouble("width").toFloat(),
+                height = json.getDouble("height").toFloat(),
+                text = json.getString("text")
+            )
+            listener.onTextSelected(rect)
+        } catch (e: Exception) {
+            Timber.e(e, "Error parsing selection rect JSON")
+        }
+    }
+
+    @JavascriptInterface
+    fun onSelectionCleared() {
+        listener.onSelectionCleared()
+    }
+}
+
+class PageInfoBridge(
+    private val onUpdate: (scrollY: Int, scrollHeight: Int, clientHeight: Int, activeFragmentId: String?) -> Unit
+) {
+    @JavascriptInterface
+    fun updateScrollState(scrollY: Int, scrollHeight: Int, clientHeight: Int, activeFragmentId: String?) {
+        val fragment = if (activeFragmentId == "null" || activeFragmentId.isNullOrBlank()) null else activeFragmentId
+        Timber.tag("FRAG_NAV_DEBUG").d("Bridge received fragmentId: $fragment")
+        onUpdate(scrollY, scrollHeight, clientHeight, fragment)
+    }
+}