refactor tmuxedit to Agent interface with cursor/claude/config implementations

Replace monolithic AgentConfig struct with an Agent interface backed by
baseAgent defaults and separate implementations for cursor (box-drawing
extraction, bulk backspace clearing) and claude (section-scoped extraction
with continuation lines, vim clearing). Simple agents (amp, aider) and
user-defined agents use configAgent with baseAgent defaults.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 129 insertions, 0 deletions

diff --git a/internal/tmuxedit/claude_agent_test.go b/internal/tmuxedit/claude_agent_test.go
new file mode 100644
index 0000000..a373378
--- /dev/null
+++ b/internal/tmuxedit/claude_agent_test.go
@@ -0,0 +1,129 @@
+package tmuxedit
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+)
+
+func TestClaudeAgent_ExtractPrompt(t *testing.T) {
+	agent := newClaudeAgent()
+	tests := []struct {
+		name    string
+		content string
+		want    string
+	}{
+		{
+			name:    "single line",
+			content: "──────\n❯ hello world\n──────",
+			want:    "hello world",
+		},
+		{
+			name: "multi-line between rules",
+			content: "previous output\n" +
+				"──────────────\n" +
+				"❯ first line\n" +
+				"\n" +
+				"❯ second line\n" +
+				"\n" +
+				"❯ third line\n" +
+				"──────────────\n" +
+				"  -- INSERT --",
+			want: "first line\nsecond line\nthird line",
+		},
+		{
+			name: "wrapped long line",
+			content: "──────────────\n" +
+				"❯ This is a really long prompt that wraps\n" +
+				"  to a second line in the terminal\n" +
+				"──────────────\n" +
+				"  -- INSERT --",
+			want: "This is a really long prompt that wraps\nto a second line in the terminal",
+		},
+		{
+			name: "ignores previous messages",
+			content: "──────────────\n" +
+				"❯ old user message\n" +
+				"──────────────\n" +
+				"assistant response here\n" +
+				"──────────────\n" +
+				"❯ current prompt\n" +
+				"──────────────\n" +
+				"  -- INSERT --",
+			want: "current prompt",
+		},
+		{
+			name:    "no match",
+			content: "no prompt here",
+			want:    "",
+		},
+		{
+			name:    "no section delimiters",
+			content: "❯ hello world",
+			want:    "hello world",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := agent.ExtractPrompt(tt.content)
+			if got != tt.want {
+				t.Errorf("ExtractPrompt() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestClaudeAgent_ClearInput(t *testing.T) {
+	noSleep(t)
+	var calls []string
+	oldSend := sendKeys
+	defer func() { sendKeys = oldSend }()
+	sendKeys = func(paneID string, keys ...string) error {
+		calls = append(calls, fmt.Sprintf("send:%s:%s", paneID, strings.Join(keys, ",")))
+		return nil
+	}
+
+	agent := newClaudeAgent()
+	err := agent.ClearInput("%3")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	// "Escape gg C-v G d i" should send each as separate send-keys call
+	want := []string{
+		"send:%3:Escape",
+		"send:%3:gg",
+		"send:%3:C-v",
+		"send:%3:G",
+		"send:%3:d",
+		"send:%3:i",
+	}
+	if len(calls) != len(want) {
+		t.Fatalf("got %d calls, want %d: %v", len(calls), len(want), calls)
+	}
+	for i, w := range want {
+		if calls[i] != w {
+			t.Errorf("call[%d] = %q, want %q", i, calls[i], w)
+		}
+	}
+}
+
+func TestClaudeAgent_Detect(t *testing.T) {
+	agent := newClaudeAgent()
+	tests := []struct {
+		name    string
+		content string
+		want    bool
+	}{
+		{"prompt symbol", "❯ hello", true},
+		{"claude code banner", "claude code v1.0", true},
+		{"anthropic mention", "Powered by Anthropic", true},
+		{"no match", "some text", false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := agent.Detect(tt.content); got != tt.want {
+				t.Errorf("Detect() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}