From 2b5c8707aa71295bee9691802d83bee9a5d9d520 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Sat, 30 May 2026 13:26:53 +0000
Subject: [PATCH] feat(core): implement table rendering in ANSIRenderer
 (core-markdown-parsing TASK-03)

Two-pass column-width scan for alignment, box-drawing separators, and
safe truncation at 80 columns for wide tables.

https://claude.ai/code/session_01RinwPH9x34irgsdU7FoUNK
---
 Sources/Core/ANSIRenderer.swift     | 63 +++++++++++++++++++++++++++++
 docs/specs/core-markdown-parsing.md |  2 +-
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/Sources/Core/ANSIRenderer.swift b/Sources/Core/ANSIRenderer.swift
index b87e5f4..619b86e 100644
--- a/Sources/Core/ANSIRenderer.swift
+++ b/Sources/Core/ANSIRenderer.swift
@@ -15,6 +15,13 @@ public struct ANSIRenderer: MarkupVisitor {
 
     public init() {}
 
+    private func plainText(from markup: any Markup) -> String {
+        if let text = markup as? Text {
+            return text.string
+        }
+        return markup.children.map { plainText(from: $0) }.joined()
+    }
+
     public func render(_ document: MarkdownDocument) -> String {
         var renderer = self
         return renderer.visit(document.document)
@@ -133,6 +140,62 @@ public struct ANSIRenderer: MarkupVisitor {
         return items.joined(separator: "\n")
     }
 
+    public mutating func visitTable(_ table: Table) -> String {
+        let headRows = table.head.children.compactMap { $0 as? Table.Row }
+        let bodyRows = table.body.children.compactMap { $0 as? Table.Row }
+        let allRows = headRows + bodyRows
+        guard !allRows.isEmpty else { return "" }
+
+        let cellTexts: [[String]] = allRows.map { row in
+            row.children.compactMap { $0 as? Table.Cell }.map { plainText(from: $0) }
+        }
+        let columnWidths = computeColumnWidths(from: cellTexts)
+        guard !columnWidths.isEmpty else { return "" }
+
+        var lines: [String] = []
+        lines.append(tableSeparator(columnWidths: columnWidths, left: "┌", mid: "┬", right: "┐"))
+        for rowIdx in headRows.indices {
+            lines.append(tableRow(cellTexts[rowIdx], columnWidths: columnWidths, bold: true))
+        }
+        if !headRows.isEmpty {
+            lines.append(tableSeparator(columnWidths: columnWidths, left: "├", mid: "┼", right: "┤"))
+        }
+        let headCount = headRows.count
+        for rowIdx in bodyRows.indices {
+            lines.append(tableRow(cellTexts[headCount + rowIdx], columnWidths: columnWidths, bold: false))
+        }
+        lines.append(tableSeparator(columnWidths: columnWidths, left: "└", mid: "┴", right: "┘"))
+        return lines.joined(separator: "\n")
+    }
+
+    private func computeColumnWidths(from cellTexts: [[String]]) -> [Int] {
+        let columnCount = cellTexts.map(\.count).max() ?? 0
+        guard columnCount > 0 else { return [] }
+        var widths = Array(repeating: 0, count: columnCount)
+        for row in cellTexts {
+            for (idx, text) in row.enumerated() where idx < columnCount {
+                widths[idx] = max(widths[idx], text.count)
+            }
+        }
+        return widths
+    }
+
+    private func tableSeparator(columnWidths: [Int], left: String, mid: String, right: String) -> String {
+        let inner = columnWidths.map { String(repeating: "─", count: $0 + 2) }.joined(separator: mid)
+        let line = left + inner + right
+        return line.count > 80 ? String(line.prefix(80)) : line
+    }
+
+    private func tableRow(_ cells: [String], columnWidths: [Int], bold: Bool) -> String {
+        let parts = columnWidths.indices.map { idx -> String in
+            let text = idx < cells.count ? cells[idx] : ""
+            let padded = text + String(repeating: " ", count: max(0, columnWidths[idx] - text.count))
+            return bold ? " \(ANSI.bold)\(padded)\(ANSI.reset) " : " \(padded) "
+        }
+        let line = "│" + parts.joined(separator: "│") + "│"
+        return line.count > 80 ? String(line.prefix(80)) : line
+    }
+
     public mutating func visitSoftBreak(_ softBreak: SoftBreak) -> String {
         "\n"
     }
diff --git a/docs/specs/core-markdown-parsing.md b/docs/specs/core-markdown-parsing.md
index 46ba9bc..069d11c 100644
--- a/docs/specs/core-markdown-parsing.md
+++ b/docs/specs/core-markdown-parsing.md
@@ -58,7 +58,7 @@ Implements the `MarkdownDocument` model and a terminal renderer that converts pa
 - [ ] Tables with varying column widths align correctly.
 - [ ] A table wider than the terminal width does not crash — it truncates or wraps gracefully.
 
-**Status:** todo
+**Status:** done
 
 ---