feat: patch view in email

config/default_keybinds.json

@@ -26,7 +26,8 @@
     "rsvp_accept": "1",
     "rsvp_decline": "2",
     "rsvp_tentative": "3",
-    "focus_attachments": "tab"
+    "focus_attachments": "tab",
+    "apply_patch": "p"
   },
   "composer": {
     "external_editor": "ctrl+e",

config/keybinds.go

@@ -56,6 +56,7 @@ type EmailKeys struct {
 	RsvpDecline      string `json:"rsvp_decline"`
 	RsvpTentative    string `json:"rsvp_tentative"`
 	FocusAttachments string `json:"focus_attachments"`
+	ApplyPatch       string `json:"apply_patch"`
 }
 
 type ComposerKeys struct {
@@ -134,6 +135,7 @@ func ValidateKeybinds(kb KeybindsConfig) []string {
 			"rsvp_decline":      kb.Email.RsvpDecline,
 			"rsvp_tentative":    kb.Email.RsvpTentative,
 			"focus_attachments": kb.Email.FocusAttachments,
+			"apply_patch":       kb.Email.ApplyPatch,
 		},
 		"composer": {
 			"external_editor": kb.Composer.ExternalEditor,

tui/email_view.go

@@ -11,6 +11,7 @@
 	tea "charm.land/bubbletea/v2"
 	"charm.land/lipgloss/v2"
 	calendar "github.com/floatpane/go-icalendar"
+	mailpatch "github.com/floatpane/go-mailpatch"
 	"github.com/floatpane/matcha/config"
 	"github.com/floatpane/matcha/fetcher"
 	"github.com/floatpane/matcha/theme"
@@ -75,6 +76,10 @@
 	originalICSData    []byte
 	isPreviewMode      bool
 	columnOffset       int // horizontal offset for image rendering in split pane
+	isPatch            bool
+	patch              *mailpatch.Patch
+	patchRaw           []byte
+	patchStatus        string
 }
 
 func NewEmailView(email fetcher.Email, emailIndex, width, height int, mailbox MailboxKind, disableImages bool) *EmailView {
@@ -157,8 +162,15 @@
 	vp := viewport.New()
 	vp.SetWidth(width)
 	vp.SetHeight(height - headerHeight - attachmentHeight - calendarHeight)
-	wrapped := wrapBodyToWidth(body, vp.Width())
-	vp.SetContent(wrapped + "\n")
+
+	// If this email is a git format-patch, render the diff in place of the
+	// plain body so the reviewer sees a colored diff.
+	patch, patchRaw, isPatch := detectPatch(email)
+	if isPatch {
+		vp.SetContent(renderPatch(patch) + "\n")
+	} else {
+		vp.SetContent(wrapBodyToWidth(body, vp.Width()) + "\n")
+	}
 
 	return &EmailView{
 		viewport:          vp,
@@ -179,6 +191,9 @@
 		calendarEvent:     calendarEvent,
 		originalICSData:   originalICSData,
 		isPreviewMode:     false,
+		isPatch:           isPatch,
+		patch:             patch,
+		patchRaw:          patchRaw,
 	}
 }
 
@@ -194,7 +209,7 @@
 	return nil
 }
 
 func (m *EmailView) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	var cmd tea.Cmd
 	cmds := make([]tea.Cmd, 0, 1)
 
@@ -312,6 +327,11 @@
 				if len(m.email.Attachments) > 0 {
 					m.focusOnAttachments = true
 				}
+			case kb.Email.ApplyPatch:
+				if m.isPatch {
+					m.patchStatus = applyOpenPatch(m.patchRaw)
+					return m, nil
+				}
 			}
 		}
 	case tea.WindowSizeMsg:
@@ -334,8 +354,12 @@
 		}
 		body = applyBodyTransform(body, m.email)
 		m.imagePlacements = placements
-		wrapped := wrapBodyToWidth(body, m.viewport.Width())
-		m.viewport.SetContent(wrapped + "\n")
+		if m.isPatch {
+			m.viewport.SetContent(renderPatch(m.patch) + "\n")
+		} else {
+			wrapped := wrapBodyToWidth(body, m.viewport.Width())
+			m.viewport.SetContent(wrapped + "\n")
+		}
 	}
 
 	m.viewport, cmd = m.viewport.Update(msg)
@@ -389,6 +413,9 @@
 		if view.ImageProtocolSupported() {
 			shortcuts.WriteString("• \uf03e i: toggle images")
 		}
+		if m.isPatch {
+			shortcuts.WriteString(" • p: apply patch")
+		}
 		for _, pk := range m.pluginKeyBindings {
 			shortcuts.WriteString(" • ")
 			shortcuts.WriteString(pk.Key)
@@ -399,6 +426,10 @@
 			shortcuts.WriteString(" • ")
 			shortcuts.WriteString(m.pluginStatus)
 		}
+		if m.patchStatus != "" {
+			shortcuts.WriteString(" • ")
+			shortcuts.WriteString(m.patchStatus)
+		}
 		help = helpStyle.Render(shortcuts.String())
 	}
 

tui/patch_view.go

@@ -0,0 +1,119 @@
+package tui
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"charm.land/lipgloss/v2"
+	mailpatch "github.com/floatpane/go-mailpatch"
+	"github.com/floatpane/matcha/fetcher"
+	"github.com/floatpane/matcha/gitmail"
+	"github.com/floatpane/matcha/theme"
+)
+
+// detectPatch reconstructs a minimal RFC 5322 message from a plain-text email
+// and parses it as a git format-patch. It returns the parsed patch and the raw
+// bytes (for applying) when the message carries a diff; otherwise ok is false.
+func detectPatch(e fetcher.Email) (patch *mailpatch.Patch, raw []byte, ok bool) {
+	if e.BodyMIMEType == "text/html" {
+		return nil, nil, false
+	}
+	raw = reconstructPatchMessage(e)
+	parsed, err := mailpatch.ParseBytes(raw)
+	if err != nil || !parsed.HasDiff() {
+		return nil, nil, false
+	}
+	return parsed, raw, true
+}
+
+// reconstructPatchMessage rebuilds the headers go-mailpatch needs (From,
+// Subject) around the raw body, so the subject's "[PATCH n/m]" prefix and the
+// author are parsed alongside the diff.
+func reconstructPatchMessage(e fetcher.Email) []byte {
+	var b strings.Builder
+	b.WriteString("From: ")
+	b.WriteString(e.From)
+	b.WriteString("\nSubject: ")
+	b.WriteString(e.Subject)
+	b.WriteString("\n\n")
+	b.WriteString(e.Body)
+	return []byte(b.String())
+}
+
+// renderPatch produces a colored, scrollable rendering of a parsed patch: a
+// summary banner, the commit message, then each file's hunks with additions in
+// green and deletions in red.
+func renderPatch(p *mailpatch.Patch) string {
+	add := lipgloss.NewStyle().Foreground(theme.ActiveTheme.Tip)
+	del := lipgloss.NewStyle().Foreground(theme.ActiveTheme.Danger)
+	hunkStyle := lipgloss.NewStyle().Foreground(theme.ActiveTheme.Accent)
+	fileHdr := lipgloss.NewStyle().Bold(true).Foreground(theme.ActiveTheme.Accent)
+	meta := lipgloss.NewStyle().Foreground(theme.ActiveTheme.MutedText)
+
+	var b strings.Builder
+
+	if p.Series.Total > 0 {
+		fmt.Fprintf(&b, "%s\n", meta.Render(
+			fmt.Sprintf("Patch %d/%d (v%d)", p.Series.Index, p.Series.Total, p.Series.Version)))
+	}
+	fmt.Fprintf(&b, "%s\n\n", meta.Render(
+		fmt.Sprintf("%d file(s) changed, +%d -%d", p.Stat.FilesChanged, p.Stat.Additions, p.Stat.Deletions)))
+
+	if msg := strings.TrimSpace(p.Body); msg != "" {
+		b.WriteString(msg)
+		b.WriteString("\n\n")
+	}
+
+	for _, f := range p.Files {
+		fmt.Fprintf(&b, "%s\n", fileHdr.Render(fileHeading(f)))
+		if f.IsBinary {
+			b.WriteString(meta.Render("  (binary file)"))
+			b.WriteString("\n\n")
+			continue
+		}
+		for _, h := range f.Hunks {
+			head := strings.TrimRight(fmt.Sprintf("@@ -%d,%d +%d,%d @@ %s",
+				h.OldStart, h.OldLines, h.NewStart, h.NewLines, h.Section), " ")
+			fmt.Fprintf(&b, "%s\n", hunkStyle.Render(head))
+			for _, ln := range h.Lines {
+				switch ln.Kind {
+				case mailpatch.Add:
+					b.WriteString(add.Render("+" + ln.Text))
+				case mailpatch.Delete:
+					b.WriteString(del.Render("-" + ln.Text))
+				case mailpatch.Context:
+					b.WriteString(" " + ln.Text)
+				}
+				b.WriteByte('\n')
+			}
+		}
+		b.WriteByte('\n')
+	}
+	return b.String()
+}
+
+func fileHeading(f mailpatch.FileChange) string {
+	switch f.Type {
+	case mailpatch.Renamed, mailpatch.Copied:
+		return fmt.Sprintf("%s: %s -> %s", f.Type, f.OldPath, f.NewPath)
+	case mailpatch.Added, mailpatch.Deleted, mailpatch.Modified:
+		return fmt.Sprintf("%s: %s", f.Type, f.Path())
+	default:
+		return fmt.Sprintf("%s: %s", f.Type, f.Path())
+	}
+}
+
+// applyOpenPatch applies the patch to the current working directory and returns
+// a human-readable status line for the help bar.
+func applyOpenPatch(raw []byte) string {
+	wd, err := os.Getwd()
+	if err != nil {
+		wd = "."
+	}
+	summary, err := gitmail.Apply(raw, ".", gitmail.Options{})
+	if err != nil {
+		return "✗ apply failed: " + err.Error()
+	}
+	return fmt.Sprintf("✓ applied %d file(s) into %s", len(summary.Files), wd)
+}

tui/patch_view_test.go

@@ -0,0 +1,83 @@
+package tui
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/floatpane/matcha/fetcher"
+)
+
+const patchBody = `commit message here
+
+---
+ greet.txt | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/greet.txt b/greet.txt
+index 111..222 100644
+--- a/greet.txt
++++ b/greet.txt
+@@ -1,3 +1,3 @@
+ hello
+-world
++there
+ bye
+`
+
+func patchEmail() fetcher.Email {
+	return fetcher.Email{
+		From:         "Ada <ada@example.com>",
+		Subject:      "[PATCH 2/3] greet: change the world",
+		Body:         patchBody,
+		BodyMIMEType: "text/plain",
+	}
+}
+
+func TestDetectPatch(t *testing.T) {
+	p, raw, ok := detectPatch(patchEmail())
+	if !ok {
+		t.Fatal("detectPatch = false for a patch email")
+	}
+	if p.Subject != "greet: change the world" {
+		t.Errorf("Subject = %q", p.Subject)
+	}
+	if p.Series.Index != 2 || p.Series.Total != 3 {
+		t.Errorf("Series = %+v", p.Series)
+	}
+	if len(raw) == 0 {
+		t.Error("raw is empty")
+	}
+}
+
+func TestDetectPatchRejectsHTML(t *testing.T) {
+	e := patchEmail()
+	e.BodyMIMEType = "text/html"
+	if _, _, ok := detectPatch(e); ok {
+		t.Error("detectPatch should reject HTML bodies")
+	}
+}
+
+func TestDetectPatchRejectsPlainEmail(t *testing.T) {
+	e := fetcher.Email{
+		From:         "Bob <bob@example.com>",
+		Subject:      "lunch?",
+		Body:         "want to grab lunch tomorrow?\n",
+		BodyMIMEType: "text/plain",
+	}
+	if _, _, ok := detectPatch(e); ok {
+		t.Error("detectPatch should reject a non-patch email")
+	}
+}
+
+func TestRenderPatch(t *testing.T) {
+	p, _, ok := detectPatch(patchEmail())
+	if !ok {
+		t.Fatal("detectPatch failed")
+	}
+	out := renderPatch(p)
+	for _, want := range []string{"greet.txt", "world", "there", "Patch 2/3"} {
+		if !strings.Contains(out, want) {
+			t.Errorf("rendered patch missing %q", want)
+		}
+	}
+}