feat(chat): show read and write file contents in code viewer card (#1238)

app/src/androidTest/java/com/m57/hermescontrol/ui/chat/FileToolBubbleTest.kt

@@ -0,0 +1,95 @@
+package com.m57.hermescontrol.ui.chat
+
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.MediumTest
+import com.m57.hermescontrol.theme.HermesControlTheme
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+@MediumTest
+class FileToolBubbleTest {
+    @get:Rule
+    val composeRule = createComposeRule()
+
+    @Test
+    fun tappingReadFileBubbleShowsFileViewCardWithSyntaxViewer() {
+        val payload =
+            """
+            {
+              "args": {"path": "/repo/src/Main.kt", "offset": 1, "limit": 2},
+              "result": {"content": "1|fun main() {\n2|    println(\"hi\")\n3|}"}
+            }
+            """.trimIndent()
+
+        showBubble("read_file", payload)
+
+        composeRule.onNodeWithText("Read Main.kt L1-2", substring = true).performClick()
+        composeRule.onNodeWithTag("file_view_card", useUnmergedTree = true).assertExists()
+        composeRule.onNodeWithText("/repo/src/Main.kt", useUnmergedTree = true).assertExists()
+        composeRule.onNodeWithText("3 lines", useUnmergedTree = true).assertExists()
+    }
+
+    @Test
+    fun tappingWriteFileBubbleShowsFileViewCardWhenNoDiff() {
+        val payload =
+            """
+            {
+              "args": {
+                "path": "/repo/src/Config.json",
+                "content": "{\n  \"enabled\": true\n}"
+              },
+              "result": {"verified": true, "success": true}
+            }
+            """.trimIndent()
+
+        showBubble("write_file", payload)
+
+        composeRule.onNodeWithText("Config.json", substring = true).performClick()
+        composeRule.onNodeWithTag("file_view_card", useUnmergedTree = true).assertExists()
+        composeRule.onNodeWithText("/repo/src/Config.json", useUnmergedTree = true).assertExists()
+        composeRule.onNodeWithText("3 lines", useUnmergedTree = true).assertExists()
+    }
+
+    @Test
+    fun tappingWriteFileWithDiffShowsDiffViewCard() {
+        val payload =
+            """
+            {
+              "args": {"path": "/repo/src/Utils.kt"},
+              "result": {
+                "inline_diff": "--- a/Utils.kt\n+++ b/Utils.kt\n@@ -1,1 +1,1 @@\n-old\n+new"
+              }
+            }
+            """.trimIndent()
+
+        showBubble("write_file", payload)
+
+        composeRule.onNodeWithText("Utils.kt", substring = true).performClick()
+        composeRule.onNodeWithTag("diff_view_card", useUnmergedTree = true).assertExists()
+        composeRule.onNodeWithText("Utils.kt", useUnmergedTree = true).assertExists()
+    }
+
+    private fun showBubble(
+        name: String,
+        content: String,
+    ) {
+        composeRule.setContent {
+            HermesControlTheme {
+                ToolBubble(
+                    ChatMessage(
+                        role = MessageRole.TOOL,
+                        content = content,
+                        toolName = name,
+                        toolStatus = ToolStatus.COMPLETED,
+                    ),
+                )
+            }
+        }
+    }
+}

app/src/androidTest/java/com/m57/hermescontrol/ui/chat/components/FileViewCardTest.kt

@@ -0,0 +1,78 @@
+package com.m57.hermescontrol.ui.chat.components
+
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onNodeWithContentDescription
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.MediumTest
+import org.junit.Assert.assertEquals
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+@MediumTest
+class FileViewCardTest {
+    @get:Rule
+    val composeTestRule = createComposeRule()
+
+    @Test
+    fun shortFile_displaysPathLineCountAndFullContentWithoutExpandButton() {
+        val content = "fun hello() = println(\"world\")\nval x = 42"
+        var copiedText = ""
+
+        composeTestRule.setContent {
+            FileViewCard(
+                content = content,
+                filePath = "src/main/Test.kt",
+                onCopy = { copiedText = it },
+            )
+        }
+
+        composeTestRule.onNodeWithTag("file_view_card").assertIsDisplayed()
+        composeTestRule.onNodeWithText("src/main/Test.kt").assertIsDisplayed()
+        composeTestRule.onNodeWithText("2 lines").assertIsDisplayed()
+        composeTestRule.onNodeWithText("Show full file (2 lines)").assertDoesNotExist()
+
+        composeTestRule.onNodeWithTag("file_view_card").assertIsDisplayed()
+    }
+
+    @Test
+    fun longFile_showsExpandButtonAndTogglesFullFile() {
+        val lines = (1..25).map { "line $it: println($it)" }
+        val content = lines.joinToString("\n")
+
+        composeTestRule.setContent {
+            FileViewCard(
+                content = content,
+                filePath = "src/Big.kt",
+            )
+        }
+
+        composeTestRule.onNodeWithText("Show full file (25 lines)").assertIsDisplayed()
+        composeTestRule.onNodeWithText("Show full file (25 lines)").performClick()
+        composeTestRule.onNodeWithText("Collapse file").assertIsDisplayed()
+        composeTestRule.onNodeWithText("Collapse file").performClick()
+        composeTestRule.onNodeWithText("Show full file (25 lines)").assertIsDisplayed()
+    }
+
+    @Test
+    fun copyButton_invokesCallbackWithFullContent() {
+        val content = "1|fun main() = Unit"
+        var copied = ""
+
+        composeTestRule.setContent {
+            FileViewCard(
+                content = content,
+                filePath = "src/App.kt",
+                onCopy = { copied = it },
+            )
+        }
+        composeTestRule.onNodeWithText("src/App.kt").assertIsDisplayed()
+        composeTestRule.onNodeWithContentDescription("Copy file content").performClick()
+        assertEquals(content, copied)
+    }
+}

app/src/main/java/com/m57/hermescontrol/ui/chat/ToolBubble.kt

@@ -75,7 +75,9 @@ import com.m57.hermescontrol.theme.CodeTerminalMuted
 import com.m57.hermescontrol.theme.CodeTerminalText
 import com.m57.hermescontrol.theme.HermesStatusColors
 import com.m57.hermescontrol.theme.LocalHermesStatusColors
+import com.m57.hermescontrol.ui.chat.components.CodeTerminalCard
 import com.m57.hermescontrol.ui.chat.components.DiffViewCard
+import com.m57.hermescontrol.ui.chat.components.FileViewCard
 import com.m57.hermescontrol.ui.chat.components.highlightSyntax
 import com.m57.hermescontrol.ui.chat.tool.ToolJson
 import com.m57.hermescontrol.ui.chat.tool.ToolView
@@ -423,6 +425,11 @@ private fun ExpandedToolContent(
                     diffText = view.inlineDiff,
                     filePath = view.diffPath,
                 )
+            } else if (view.fileContent != null) {
+                FileViewCard(
+                    content = view.fileContent,
+                    filePath = view.filePath,
+                )
             }
 
             // ── Search hits ──
@@ -478,7 +485,7 @@ private fun ExpandedToolContent(
             }
 
             // ── Plain detail body ──
-            if (view.detail.isNotBlank() && view.inlineDiff == null) {
+            if (view.detail.isNotBlank() && view.inlineDiff == null && view.fileContent == null) {
                 Text(
                     text = view.detail,
                     modifier =
@@ -636,42 +643,13 @@ private fun ToolRawJsonView(
             }
     }
 
-    val clipboard = LocalClipboard.current
+    CodeTerminalCard(
-    val scope = rememberCoroutineScope()
+        textToCopy = displayText,
-    var copied by remember { mutableStateOf(false) }
+        modifier = modifier,
-    LaunchedEffect(copied) {
+        testTag = "tool_raw_json",
-        if (copied) {
+        title = "JSON",
-            delay(2000)
+        copyContentDescription = stringResource(R.string.content_desc_copy),
-            copied = false
+        headerActions = {
-        }
-    }
-
-    Surface(
-        modifier =
-            modifier
-                .fillMaxWidth()
-                .testTag("tool_raw_json"),
-        shape = RoundedCornerShape(8.dp),
-        color = CodeTerminalBg,
-        border = BorderStroke(1.dp, CodeTerminalBorder),
-    ) {
-        Column {
-            Row(
-                modifier =
-                    Modifier
-                        .fillMaxWidth()
-                        .padding(horizontal = 8.dp, vertical = 4.dp),
-                verticalAlignment = Alignment.CenterVertically,
-            ) {
-                Text(
-                    text = "JSON",
-                    style =
-                        MaterialTheme.typography.labelSmall.copy(
-                            fontWeight = FontWeight.Bold,
-                            color = CodeTerminalMuted,
-                        ),
-                )
-                Spacer(Modifier.weight(1f))
             if (isFormatDifferent) {
                 Text(
                     text =
@@ -692,28 +670,8 @@ private fun ToolRawJsonView(
                             .padding(horizontal = 6.dp, vertical = 2.dp),
                 )
             }
-                IconButton(
-                    onClick = {
-                        scope.launch {
-                            clipboard.setClipEntry(ClipEntry(ClipData.newPlainText(null, displayText)))
-                        }
-                        copied = true
         },
-                    modifier = Modifier.size(28.dp),
     ) {
-                    Icon(
-                        imageVector = if (copied) Icons.Filled.Check else Icons.Filled.ContentCopy,
-                        contentDescription =
-                            if (copied) {
-                                stringResource(R.string.content_desc_copied)
-                            } else {
-                                stringResource(R.string.content_desc_copy)
-                            },
-                        tint = CodeTerminalMuted,
-                        modifier = Modifier.size(14.dp),
-                    )
-                }
-            }
         SelectionContainer {
             Text(
                 text = highlighted,
@@ -731,7 +689,6 @@ private fun ToolRawJsonView(
         }
     }
 }
-}
 
 @Composable
 private fun CopyButton(

app/src/main/java/com/m57/hermescontrol/ui/chat/components/CodeTerminalCard.kt

@@ -0,0 +1,193 @@
+package com.m57.hermescontrol.ui.chat.components
+
+import android.content.ClipData
+import android.content.ClipboardManager
+import android.content.Context
+import androidx.compose.animation.animateContentSize
+import androidx.compose.foundation.BorderStroke
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.RowScope
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Check
+import androidx.compose.material.icons.filled.ContentCopy
+import androidx.compose.material.icons.filled.ExpandLess
+import androidx.compose.material.icons.filled.ExpandMore
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import com.m57.hermescontrol.R
+import com.m57.hermescontrol.theme.CodeTerminalBg
+import com.m57.hermescontrol.theme.CodeTerminalBorder
+import com.m57.hermescontrol.theme.CodeTerminalMuted
+import com.m57.hermescontrol.theme.CodeTerminalText
+import kotlinx.coroutines.delay
+
+/**
+ * Shared container card for terminal-styled code, diff, and JSON viewers.
+ *
+ * Provides the dark terminal surface, consistent header row with leading icon/label,
+ * optional status badges/actions, animated copy-to-clipboard button, content body slot,
+ * and optional collapsible footer.
+ */
+@Composable
+fun CodeTerminalCard(
+    textToCopy: String,
+    modifier: Modifier = Modifier,
+    testTag: String? = null,
+    title: String? = null,
+    icon: ImageVector? = null,
+    clipLabel: String? = null,
+    copyContentDescription: String = stringResource(R.string.content_desc_copy),
+    onCopy: ((String) -> Unit)? = null,
+    headerLeading: (@Composable RowScope.() -> Unit)? = null,
+    headerActions: (@Composable RowScope.() -> Unit)? = null,
+    totalLines: Int? = null,
+    collapsibleThreshold: Int = 16,
+    isExpanded: Boolean = false,
+    onToggleExpand: (() -> Unit)? = null,
+    expandLabel: String = "Show full",
+    collapseLabel: String = "Collapse",
+    content: @Composable () -> Unit,
+) {
+    val context = LocalContext.current
+    var copied by remember { mutableStateOf(false) }
+
+    LaunchedEffect(copied) {
+        if (copied) {
+            delay(2000)
+            copied = false
+        }
+    }
+
+    Surface(
+        modifier =
+            modifier
+                .fillMaxWidth()
+                .then(if (testTag != null) Modifier.testTag(testTag) else Modifier),
+        shape = RoundedCornerShape(8.dp),
+        color = CodeTerminalBg,
+        border = BorderStroke(1.dp, CodeTerminalBorder),
+    ) {
+        Column(modifier = Modifier.animateContentSize()) {
+            // Header bar
+            Row(
+                modifier =
+                    Modifier
+                        .fillMaxWidth()
+                        .padding(horizontal = 10.dp, vertical = 6.dp),
+                verticalAlignment = Alignment.CenterVertically,
+            ) {
+                Row(
+                    modifier = Modifier.weight(1f),
+                    verticalAlignment = Alignment.CenterVertically,
+                ) {
+                    if (headerLeading != null) {
+                        headerLeading()
+                    } else {
+                        if (icon != null) {
+                            Icon(
+                                imageVector = icon,
+                                contentDescription = null,
+                                tint = CodeTerminalMuted,
+                                modifier = Modifier.size(16.dp),
+                            )
+                            Spacer(Modifier.width(6.dp))
+                        }
+                        if (!title.isNullOrBlank()) {
+                            Text(
+                                text = title,
+                                style =
+                                    MaterialTheme.typography.labelMedium.copy(
+                                        fontWeight = FontWeight.Bold,
+                                        fontFamily = FontFamily.Monospace,
+                                        color = CodeTerminalText,
+                                    ),
+                                maxLines = 1,
+                                overflow = TextOverflow.Ellipsis,
+                                modifier = Modifier.weight(1f, fill = false),
+                            )
+                            Spacer(Modifier.width(8.dp))
+                        }
+                    }
+
+                    headerActions?.invoke(this)
+                }
+
+                IconButton(
+                    onClick = {
+                        val clipboard =
+                            context.getSystemService(Context.CLIPBOARD_SERVICE) as? ClipboardManager
+                        clipboard?.setPrimaryClip(ClipData.newPlainText(clipLabel, textToCopy))
+                        copied = true
+                        onCopy?.invoke(textToCopy)
+                    },
+                    modifier = Modifier.size(28.dp),
+                ) {
+                    Icon(
+                        imageVector = if (copied) Icons.Filled.Check else Icons.Filled.ContentCopy,
+                        contentDescription =
+                            if (copied) {
+                                stringResource(R.string.content_desc_copied)
+                            } else {
+                                copyContentDescription
+                            },
+                        tint = CodeTerminalMuted,
+                        modifier = Modifier.size(14.dp),
+                    )
+                }
+            }
+
+            // Body
+            content()
+
+            // Expand / Collapse footer button
+            if (totalLines != null && totalLines > collapsibleThreshold && onToggleExpand != null) {
+                TextButton(
+                    onClick = onToggleExpand,
+                    modifier = Modifier.fillMaxWidth(),
+                ) {
+                    Row(verticalAlignment = Alignment.CenterVertically) {
+                        Text(
+                            text = if (isExpanded) collapseLabel else expandLabel,
+                            style = MaterialTheme.typography.labelSmall,
+                            color = CodeTerminalMuted,
+                        )
+                        Spacer(Modifier.width(4.dp))
+                        Icon(
+                            imageVector = if (isExpanded) Icons.Filled.ExpandLess else Icons.Filled.ExpandMore,
+                            contentDescription = null,
+                            tint = CodeTerminalMuted,
+                            modifier = Modifier.size(16.dp),
+                        )
+                    }
+                }
+            }
+        }
+    }
+}

app/src/main/java/com/m57/hermescontrol/ui/chat/components/DiffViewCard.kt

@@ -1,51 +1,33 @@
 package com.m57.hermescontrol.ui.chat.components
 
-import android.content.ClipData
-import android.content.ClipboardManager
-import android.content.Context
-import androidx.compose.animation.animateContentSize
-import androidx.compose.foundation.BorderStroke
 import androidx.compose.foundation.background
 import androidx.compose.foundation.horizontalScroll
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.IntrinsicSize
-import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.heightIn
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.rememberScrollState
-import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.foundation.text.selection.SelectionContainer
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.InsertDriveFile
-import androidx.compose.material.icons.filled.Check
-import androidx.compose.material.icons.filled.ContentCopy
-import androidx.compose.material.icons.filled.ExpandLess
-import androidx.compose.material.icons.filled.ExpandMore
-import androidx.compose.material3.Icon
-import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
-import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.produceState
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
-import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.AnnotatedString
-import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.font.FontWeight
-import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.m57.hermescontrol.theme.CodeDiffAddBg
@@ -54,11 +36,10 @@ import com.m57.hermescontrol.theme.CodeDiffDeleteBg
 import com.m57.hermescontrol.theme.CodeDiffDeleteText
 import com.m57.hermescontrol.theme.CodeDiffHunkBg
 import com.m57.hermescontrol.theme.CodeDiffHunkText
-import com.m57.hermescontrol.theme.CodeTerminalBg
-import com.m57.hermescontrol.theme.CodeTerminalBorder
 import com.m57.hermescontrol.theme.CodeTerminalMuted
 import com.m57.hermescontrol.theme.CodeTerminalText
-import kotlinx.coroutines.delay
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 
 enum class DiffLineType {
     FILE_HEADER,
@@ -169,17 +150,8 @@ fun DiffViewCard(
     onCopy: (String) -> Unit = {},
     modifier: Modifier = Modifier,
 ) {
-    val context = LocalContext.current
     val parsed = remember(diffText, filePath) { parseDiffText(diffText, filePath) }
     var expanded by remember { mutableStateOf(false) }
-    var copied by remember { mutableStateOf(false) }
-
-    LaunchedEffect(copied) {
-        if (copied) {
-            delay(2000)
-            copied = false
-        }
-    }
 
     val displayLines =
         if (expanded || parsed.lines.size <= 16) {
@@ -188,50 +160,16 @@ fun DiffViewCard(
             parsed.lines.take(16)
         }
 
-    Surface(
+    CodeTerminalCard(
-        modifier =
+        textToCopy = diffText,
-            modifier
+        modifier = modifier,
-                .fillMaxWidth()
+        testTag = "diff_view_card",
-                .testTag("diff_view_card"),
+        title = parsed.filePath ?: "diff",
-        shape = RoundedCornerShape(8.dp),
+        icon = Icons.AutoMirrored.Filled.InsertDriveFile,
-        color = CodeTerminalBg,
+        clipLabel = "diff",
-        border = BorderStroke(1.dp, CodeTerminalBorder),
+        copyContentDescription = "Copy diff",
-    ) {
+        onCopy = onCopy,
-        Column(modifier = Modifier.animateContentSize()) {
+        headerActions = {
-            // Header bar
-            Row(
-                modifier =
-                    Modifier
-                        .fillMaxWidth()
-                        .padding(horizontal = 10.dp, vertical = 6.dp),
-                verticalAlignment = Alignment.CenterVertically,
-            ) {
-                Row(
-                    modifier = Modifier.weight(1f),
-                    verticalAlignment = Alignment.CenterVertically,
-                ) {
-                    Icon(
-                        imageVector = Icons.AutoMirrored.Filled.InsertDriveFile,
-                        contentDescription = null,
-                        tint = CodeTerminalMuted,
-                        modifier = Modifier.size(16.dp),
-                    )
-                    Spacer(Modifier.width(6.dp))
-                    Text(
-                        text = parsed.filePath ?: "diff",
-                        style =
-                            MaterialTheme.typography.labelMedium.copy(
-                                fontWeight = FontWeight.Bold,
-                                fontFamily = FontFamily.Monospace,
-                                color = CodeTerminalText,
-                            ),
-                        maxLines = 1,
-                        overflow = TextOverflow.Ellipsis,
-                        modifier = Modifier.weight(1f, fill = false),
-                    )
-                    Spacer(Modifier.width(8.dp))
-
-                    // Addition / Deletion badges
             if (parsed.additionsCount > 0) {
                 Text(
                     text = "+${parsed.additionsCount}",
@@ -254,28 +192,13 @@ fun DiffViewCard(
                 )
                 Spacer(Modifier.width(6.dp))
             }
-                }
-
-                IconButton(
-                    onClick = {
-                        val clipboard =
-                            context.getSystemService(Context.CLIPBOARD_SERVICE) as? ClipboardManager
-                        clipboard?.setPrimaryClip(ClipData.newPlainText("diff", diffText))
-                        copied = true
-                        onCopy(diffText)
         },
-                    modifier = Modifier.size(28.dp),
+        totalLines = parsed.lines.size,
+        isExpanded = expanded,
+        onToggleExpand = { expanded = !expanded },
+        expandLabel = "Show full diff (${parsed.lines.size} lines)",
+        collapseLabel = "Collapse diff",
     ) {
-                    Icon(
-                        imageVector = if (copied) Icons.Filled.Check else Icons.Filled.ContentCopy,
-                        contentDescription = if (copied) "Copied" else "Copy diff",
-                        tint = CodeTerminalMuted,
-                        modifier = Modifier.size(14.dp),
-                    )
-                }
-            }
-
-            // Diff lines body
         val verticalScrollModifier =
             if (expanded) {
                 Modifier.heightIn(max = 400.dp).verticalScroll(rememberScrollState())
@@ -320,34 +243,95 @@ fun DiffViewCard(
                 }
             }
         }
+    }
+}
 
-            // Expand / Collapse footer button for diffs > 16 lines
+/**
-            if (parsed.lines.size > 16) {
+ * Interactive file content view card for read_file & write_file tool outputs.
-                TextButton(
+ * Mirrors [DiffViewCard] with syntax highlighting and file path header.
-                    onClick = { expanded = !expanded },
+ */
-                    modifier = Modifier.fillMaxWidth(),
+@Composable
+fun FileViewCard(
+    content: String,
+    filePath: String? = null,
+    onCopy: (String) -> Unit = {},
+    modifier: Modifier = Modifier,
 ) {
-                    Row(verticalAlignment = Alignment.CenterVertically) {
+    var expanded by remember { mutableStateOf(false) }
-                        Text(
+    val lines = remember(content) { content.lines() }
-                            text =
+    val displayText =
-                                if (expanded) {
+        remember(content, expanded) {
-                                    "Collapse diff"
+            if (expanded || lines.size <= 16) {
+                content
             } else {
-                                    "Show full diff (${parsed.lines.size} lines)"
+                lines.take(16).joinToString("\n")
-                                },
+            }
-                            style = MaterialTheme.typography.labelSmall,
+        }
+    val highlighted by produceState(
+        initialValue = remember(displayText) { AnnotatedString(displayText) },
+        key1 = displayText,
+    ) {
+        value =
+            withContext(Dispatchers.Default) {
+                highlightSyntax(displayText)
+            }
+    }
+
+    CodeTerminalCard(
+        textToCopy = content,
+        modifier = modifier,
+        testTag = "file_view_card",
+        title = filePath?.takeIf { it.isNotBlank() } ?: "file",
+        icon = Icons.AutoMirrored.Filled.InsertDriveFile,
+        clipLabel = "file",
+        copyContentDescription = "Copy file content",
+        onCopy = onCopy,
+        headerActions = {
+            if (lines.isNotEmpty()) {
+                Text(
+                    text = "${lines.size} lines",
+                    style =
+                        MaterialTheme.typography.labelSmall.copy(
+                            fontWeight = FontWeight.Bold,
                             color = CodeTerminalMuted,
+                        ),
                 )
-                        Spacer(Modifier.width(4.dp))
+                Spacer(Modifier.width(6.dp))
-                        Icon(
+            }
-                            imageVector = if (expanded) Icons.Filled.ExpandLess else Icons.Filled.ExpandMore,
+        },
-                            contentDescription = null,
+        totalLines = lines.size,
-                            tint = CodeTerminalMuted,
+        isExpanded = expanded,
-                            modifier = Modifier.size(16.dp),
+        onToggleExpand = { expanded = !expanded },
+        expandLabel = "Show full file (${lines.size} lines)",
+        collapseLabel = "Collapse file",
+    ) {
+        val verticalScrollModifier =
+            if (expanded) {
+                Modifier.heightIn(max = 400.dp).verticalScroll(rememberScrollState())
+            } else {
+                Modifier
+            }
+
+        SelectionContainer {
+            Box(
+                modifier =
+                    Modifier
+                        .fillMaxWidth()
+                        .then(verticalScrollModifier)
+                        .horizontalScroll(rememberScrollState())
+                        .padding(horizontal = 10.dp, vertical = 6.dp),
+            ) {
+                Text(
+                    text = highlighted,
+                    style =
+                        MaterialTheme.typography.bodySmall.copy(
+                            fontFamily = FontFamily.Monospace,
+                            fontSize = 11.sp,
+                            color = CodeTerminalText,
+                        ),
+                    softWrap = false,
                 )
             }
         }
     }
 }
-    }
-}

app/src/main/java/com/m57/hermescontrol/ui/chat/components/MessageCards.kt

@@ -266,58 +266,6 @@ fun CodeBlockCard(
     onCopy: (String) -> Unit,
     modifier: Modifier = Modifier,
 ) {
-    val context = LocalContext.current
-
-    Surface(
-        modifier =
-            modifier
-                .fillMaxWidth()
-                .testTag("code_block"),
-        shape = RoundedCornerShape(8.dp),
-        color = CodeTerminalBg,
-        border = BorderStroke(1.dp, CodeTerminalBorder),
-    ) {
-        Column {
-            // Header row: language badge (left) + copy button (right)
-            Row(
-                modifier = Modifier.fillMaxWidth().padding(horizontal = 8.dp, vertical = 4.dp),
-                verticalAlignment = Alignment.CenterVertically,
-            ) {
-                if (!language.isNullOrBlank()) {
-                    Text(
-                        text = language.uppercase(),
-                        style =
-                            MaterialTheme.typography.labelSmall.copy(
-                                fontWeight = FontWeight.Bold,
-                                color = CodeTerminalMuted,
-                            ),
-                    )
-                }
-                Spacer(Modifier.weight(1f))
-                var copied by remember { mutableStateOf(false) }
-                LaunchedEffect(copied) {
-                    if (copied) {
-                        kotlinx.coroutines.delay(2000)
-                        copied = false
-                    }
-                }
-                IconButton(
-                    onClick = {
-                        copyToClipboard(context, code)
-                        copied = true
-                        onCopy(code)
-                    },
-                    modifier = Modifier.size(28.dp),
-                ) {
-                    Icon(
-                        imageVector = if (copied) Icons.Filled.Check else Icons.Filled.ContentCopy,
-                        contentDescription = if (copied) "Copied" else "Copy code",
-                        tint = CodeTerminalMuted,
-                        modifier = Modifier.size(14.dp),
-                    )
-                }
-            }
-            // Code content with syntax highlighting
     val highlighted by produceState(
         initialValue = remember(code) { AnnotatedString(code) },
         key1 = code,
@@ -327,6 +275,15 @@ fun CodeBlockCard(
                 highlightSyntax(code)
             }
     }
+
+    CodeTerminalCard(
+        textToCopy = code,
+        modifier = modifier,
+        testTag = "code_block",
+        title = language?.takeIf { it.isNotBlank() }?.uppercase(),
+        onCopy = onCopy,
+        copyContentDescription = "Copy code",
+    ) {
         Text(
             text = highlighted,
             fontFamily = FontFamily.Monospace,
@@ -340,7 +297,6 @@ fun CodeBlockCard(
         )
     }
 }
-}
 
 // Hoisted token patterns for syntax highlighting — compiled once.
 private val HIGHLIGHT_TOKENS =

app/src/main/java/com/m57/hermescontrol/ui/chat/tool/ToolRenderer.kt

@@ -50,6 +50,8 @@ internal data class ToolViewExtras(
     val inlineDiff: String? = null,
     val diffPath: String? = null,
     val diffStats: DiffStats? = null,
+    val fileContent: String? = null,
+    val filePath: String? = null,
     val searchHits: List<SearchHit>? = null,
     val searchQuery: String? = null,
 ) {

app/src/main/java/com/m57/hermescontrol/ui/chat/tool/ToolView.kt

@@ -54,6 +54,9 @@ data class ToolView(
     /** File-edit tools: the file the diff applies to. */
     val diffPath: String? = null,
     val diffStats: DiffStats? = null,
+    /** File contents shown in a syntax-highlighted code card. */
+    val fileContent: String? = null,
+    val filePath: String? = null,
     /** Image-producing tools: renderable URL (data: or http(s) image). */
     val imageUrl: String? = null,
     /** web_search: parsed result rows. */

app/src/main/java/com/m57/hermescontrol/ui/chat/tool/ToolViewBuilder.kt

@@ -116,6 +116,8 @@ object ToolViewBuilder {
             inlineDiff = clampedDiff,
             diffPath = extras.diffPath,
             diffStats = extras.diffStats,
+            fileContent = extras.fileContent?.let { ToolJson.clampForDisplay(it) },
+            filePath = extras.filePath,
             imageUrl = imageUrlFor(call.args, call.result),
             searchHits = extras.searchHits,
             searchQuery = extras.searchQuery,

app/src/main/java/com/m57/hermescontrol/ui/chat/tool/render/FileRenderers.kt

@@ -158,6 +158,21 @@ internal object ReadFileRenderer : ToolRenderer {
 
         return ToolJson.firstString(call.result, listOf("content", "text", "data", "body"))
     }
+
+    override fun extras(
+        call: ToolCall,
+        status: ToolViewStatus,
+    ): ToolViewExtras {
+        val content = ToolJson.firstString(call.result, listOf("content", "text", "data", "body"))
+        return if (content.isEmpty()) {
+            ToolViewExtras.NONE
+        } else {
+            ToolViewExtras(
+                fileContent = content,
+                filePath = ToolJson.firstString(call.args, listOf("path", "file", "filepath")),
+            )
+        }
+    }
 }
 
 /**
@@ -196,7 +211,22 @@ internal object FileEditRenderer : ToolRenderer {
         val inlineDiff = FileEditSupport.inlineDiffFromResult(call.rawResult)
 
         if (inlineDiff.isEmpty()) {
-            return ToolViewExtras.NONE
+            val content =
+                if (call.name == "write_file" && status == ToolViewStatus.SUCCESS && call.rawResult != null) {
+                    ToolJson
+                        .firstString(call.args, listOf("content"))
+                        .ifEmpty { ToolJson.firstString(call.result, listOf("content", "text", "body")) }
+                } else {
+                    ""
+                }
+            return if (content.isEmpty()) {
+                ToolViewExtras.NONE
+            } else {
+                ToolViewExtras(
+                    fileContent = content,
+                    filePath = FileEditSupport.editPath(call.args, call.result),
+                )
+            }
         }
 
         return ToolViewExtras(

app/src/test/java/com/m57/hermescontrol/ui/chat/tool/ToolViewBuilderTest.kt

@@ -81,6 +81,41 @@ class ToolViewBuilderTest {
 
         assertEquals("Read a.kt L10-14", view.title)
         assertEquals("/repo/src/a.kt", view.subtitle)
+        assertEquals("10|a\n11|b", view.fileContent)
+        assertEquals("/repo/src/a.kt", view.filePath)
+        assertEquals("10|a\n11|b", view.detail)
+    }
+
+    @Test
+    fun `read_file missing content does not show a code viewer`() {
+        val view = build("read_file", """{"path":"/repo/missing.kt"}""", """{"error":"not found"}""")
+
+        assertNull(view.fileContent)
+    }
+
+    @Test
+    fun `write_file shows written content when no diff is returned`() {
+        val view =
+            build(
+                "write_file",
+                """{"path":"/repo/new.kt","content":"fun main() = Unit"}""",
+                """{"success":true,"verified":true}""",
+            )
+
+        assertEquals("fun main() = Unit", view.fileContent)
+        assertEquals("/repo/new.kt", view.filePath)
+        assertNull(view.inlineDiff)
+    }
+
+    @Test
+    fun `write_file diff wins over content and failed writes show no written content`() {
+        val args = """{"path":"/repo/a.kt","content":"new"}"""
+        val diff = build("write_file", args, """{"inline_diff":"--- a/a.kt\n+++ b/a.kt\n-old\n+new"}""")
+        val failed = build("write_file", args, """{"success":false,"error":"denied"}""", isError = true)
+
+        assertNotNull(diff.inlineDiff)
+        assertNull(diff.fileContent)
+        assertNull(failed.fileContent)
     }
 
     @Test