Added file drag-and-drop into the message box

internal/ui/messages/input/attachment/attachment.go

@@ -66,6 +66,8 @@ type Container struct {
 	Scroll *gtk.ScrolledWindow
 	Box    *gtk.Box
 
+	enabled bool
+
 	// states
 	files []File
 	items map[string]gtk.IWidget
@@ -127,6 +129,19 @@ func (c *Container) SetMarginStart(margin int) {
 	c.Box.SetMarginStart(margin)
 }
 
+// Enabled returns whether or not the container allows attachments.
+func (c *Container) Enabled() bool {
+	return c.enabled
+}
+
+func (c *Container) SetEnabled(enabled bool) {
+	// Set the enabled state; reset the container if we're disabling the
+	// attachment box.
+	if c.enabled = enabled; !enabled {
+		c.Reset()
+	}
+}
+
 // Files returns the list of attachments
 func (c *Container) Files() []File {
 	return c.files

internal/ui/messages/input/input.go

@@ -95,19 +95,31 @@ type Field struct {
 	text       *gtk.TextView   // const
 	buffer     *gtk.TextBuffer // const
 
-	UserID string
-	Sender cchat.ServerMessageSender
-	editor cchat.ServerMessageEditor
-	typer  cchat.ServerMessageTypingIndicator
+	send   *gtk.Button
+	attach *gtk.Button
 
 	ctrl Controller
 
-	// states
+	// Embed a state field which allows us to easily reset it.
+	fieldState
+}
+
+type fieldState struct {
+	UserID string
+	Sender cchat.ServerMessageSender
+	upload bool // true if server supports files
+	editor cchat.ServerMessageEditor
+	typer  cchat.ServerMessageTypingIndicator
+
 	editingID string // never empty
 	lastTyped time.Time
 	typerDura time.Duration
 }
 
+func (s *fieldState) Reset() {
+	*s = fieldState{}
+}
+
 var inputFieldCSS = primitives.PrepareCSS(`
 	.input-field { margin: 3px 5px }
 `)
@@ -123,22 +135,23 @@ func NewField(text *gtk.TextView, ctrl Controller) *Field {
 	field.TextScroll.Show()
 	primitives.AddClass(field.TextScroll, "scrolled-input")
 
-	attach, _ := gtk.ButtonNewFromIconName("mail-attachment-symbolic", gtk.ICON_SIZE_BUTTON)
-	attach.SetRelief(gtk.RELIEF_NONE)
-	attach.Show()
-	primitives.AddClass(attach, "attach-button")
+	field.attach, _ = gtk.ButtonNewFromIconName("mail-attachment-symbolic", gtk.ICON_SIZE_BUTTON)
+	field.attach.SetRelief(gtk.RELIEF_NONE)
+	field.attach.SetSensitive(false)
+	// Only show this if the server supports it (upload == true).
+	primitives.AddClass(field.attach, "attach-button")
 
-	send, _ := gtk.ButtonNewFromIconName("mail-send-symbolic", gtk.ICON_SIZE_BUTTON)
-	send.SetRelief(gtk.RELIEF_NONE)
-	send.Show()
-	primitives.AddClass(send, "send-button")
+	field.send, _ = gtk.ButtonNewFromIconName("mail-send-symbolic", gtk.ICON_SIZE_BUTTON)
+	field.send.SetRelief(gtk.RELIEF_NONE)
+	field.send.Show()
+	primitives.AddClass(field.send, "send-button")
 
 	// Keep this number the same as size-allocate below -------v
 	field.FieldBox, _ = gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 5)
 	field.FieldBox.PackStart(field.Username, false, false, 0)
-	field.FieldBox.PackStart(attach, false, false, 0)
+	field.FieldBox.PackStart(field.attach, false, false, 0)
 	field.FieldBox.PackStart(field.TextScroll, true, true, 0)
-	field.FieldBox.PackStart(send, false, false, 0)
+	field.FieldBox.PackStart(field.send, false, false, 0)
 	field.FieldBox.Show()
 	primitives.AddClass(field.FieldBox, "input-field")
 	primitives.AttachCSS(field.FieldBox, inputFieldCSS)
@@ -156,16 +169,16 @@ func NewField(text *gtk.TextView, ctrl Controller) *Field {
 	// Bind text events.
 	text.Connect("key-press-event", field.keyDown)
 	// Bind the send button.
-	send.Connect("clicked", field.sendInput)
+	field.send.Connect("clicked", field.sendInput)
 	// Bind the attach button.
-	attach.Connect("clicked", func() { gts.SpawnUploader("", field.Attachments.AddFiles) })
+	field.attach.Connect("clicked", func() { gts.SpawnUploader("", field.Attachments.AddFiles) })
 
 	// Connect to the field's revealer. On resize, we want the attachments
 	// carousel to have the same padding too.
 	field.Username.Connect("size-allocate", func(w gtk.IWidget) {
 		// Calculate the left width: from the left of the message box to the
 		// right of the attach button, covering the username container.
-		var leftWidth = 5*2 + attach.GetAllocatedWidth() + w.ToWidget().GetAllocatedWidth()
+		var leftWidth = 5*2 + field.attach.GetAllocatedWidth() + w.ToWidget().GetAllocatedWidth()
 		// Set the autocompleter's left margin to be the same.
 		field.Attachments.SetMarginStart(leftWidth)
 	})
@@ -179,13 +192,7 @@ func (f *Field) Reset() {
 	// doing this just in case.
 	f.text.SetSensitive(false)
 
-	f.UserID = ""
-	f.Sender = nil
-	f.editor = nil
-	f.typer = nil
-	f.lastTyped = time.Time{}
-	f.typerDura = 0
-
+	f.fieldState.Reset()
 	f.Username.Reset()
 
 	// reset the input
@@ -209,6 +216,9 @@ func (f *Field) SetSender(session cchat.Session, sender cchat.ServerMessageSende
 		// Allow typer to be nil.
 		f.typer, _ = sender.(cchat.ServerMessageTypingIndicator)
 
+		// See if we can upload files.
+		_, f.upload = sender.(cchat.ServerMessageAttachmentSender)
+
 		// Populate the duration state if typer is not nil.
 		if f.typer != nil {
 			f.typerDura = f.typer.TypingTimeout()
@@ -216,6 +226,23 @@ func (f *Field) SetSender(session cchat.Session, sender cchat.ServerMessageSende
 	}
 }
 
+func (f *Field) SetAllowUpload(allow bool) {
+	f.upload = allow
+
+	// Don't allow clicks on the attachment button if allow is false.
+	f.attach.SetSensitive(allow)
+	// Disable the attachmetn carousel for good measure, which also prevents
+	// drag-and-drops.
+	f.Attachments.SetEnabled(allow)
+
+	// Show the attachment button if we can, else hide it.
+	if f.upload {
+		f.attach.Show()
+	} else {
+		f.attach.Hide()
+	}
+}
+
 // Editable returns whether or not the input field can be edited.
 func (f *Field) Editable(msgID string) bool {
 	return f.editor != nil && f.editor.MessageEditable(msgID)

internal/ui/messages/input/keydown.go

@@ -78,6 +78,12 @@ func (f *Field) keyDown(tv *gtk.TextView, ev *gdk.Event) bool {
 
 	// Ctrl+V is paste.
 	case key == gdk.KEY_v && bithas(mask, cntrlMask):
+		// As this pasting is for image attachments, don't accept it if iwe
+		// don't allow attachments.
+		if !f.upload {
+			return false
+		}
+
 		// Is there an image in the clipboard?
 		if !gts.Clipboard.WaitIsImageAvailable() {
 			// No.

internal/ui/messages/view.go

@@ -16,6 +16,7 @@ import (
 	"github.com/diamondburned/cchat-gtk/internal/ui/messages/typing"
 	"github.com/diamondburned/cchat-gtk/internal/ui/primitives"
 	"github.com/diamondburned/cchat-gtk/internal/ui/primitives/autoscroll"
+	"github.com/diamondburned/cchat-gtk/internal/ui/primitives/drag"
 	"github.com/diamondburned/cchat-gtk/internal/ui/primitives/menu"
 	"github.com/gotk3/gotk3/gtk"
 	"github.com/pkg/errors"
@@ -84,6 +85,9 @@ func NewView() *View {
 
 	primitives.AddClass(view.Box, "message-view")
 
+	// Bind a file drag-and-drop box into the main view box.
+	drag.BindFileDest(view.Box, view.InputView.Attachments.AddFiles)
+
 	// placeholder logo
 	logo, _ := gtk.ImageNewFromPixbuf(icons.Logo256Variant2(128))
 	logo.Show()

internal/ui/primitives/drag/drag.go

@@ -1,13 +1,18 @@
 package drag
 
 import (
+	"net/url"
+	"strings"
+
+	"github.com/diamondburned/cchat-gtk/internal/log"
 	"github.com/diamondburned/cchat-gtk/internal/ui/primitives"
 	"github.com/gotk3/gotk3/gdk"
 	"github.com/gotk3/gotk3/gtk"
+	"github.com/pkg/errors"
 )
 
-func NewTargetEntry(target string) gtk.TargetEntry {
-	e, _ := gtk.TargetEntryNew(target, gtk.TARGET_SAME_APP, 0)
+func NewTargetEntry(target string, f gtk.TargetFlags, info uint) gtk.TargetEntry {
+	e, _ := gtk.TargetEntryNew(target, f, info)
 	return *e
 }
 
@@ -44,6 +49,35 @@ type Draggable interface {
 	primitives.Connector
 }
 
+func BindFileDest(dg Draggable, file func(path []string)) {
+	var dragEntries = []gtk.TargetEntry{
+		NewTargetEntry("text/uri-list", gtk.TARGET_OTHER_APP, 1),
+	}
+
+	dg.DragDestSet(gtk.DEST_DEFAULT_ALL, dragEntries, gdk.ACTION_COPY)
+	dg.Connect("drag-data-received",
+		func(_ gtk.IWidget, ctx *gdk.DragContext, x, y uint, data *gtk.SelectionData) {
+			// Get the files in form of line-delimited URIs
+			var uris = strings.Fields(string(data.GetData()))
+
+			// Create a path slice that we decode URIs into.
+			var paths = uris[:0]
+
+			// Decode the URIs.
+			for _, uri := range uris {
+				u, err := url.Parse(uri)
+				if err != nil {
+					log.Error(errors.Wrapf(err, "Failed parsing URI %q", uri))
+					continue
+				}
+				paths = append(paths, u.Path)
+			}
+
+			file(paths)
+		},
+	)
+}
+
 // Swapper is the type for a swap function.
 type Swapper = func(targetID, movingID string)
 
@@ -56,8 +90,10 @@ type Swapper = func(targetID, movingID string)
 // ID will be taken from the main draggable.
 func BindDraggable(dg MainDraggable, icon string, fn Swapper, draggers ...Draggable) {
 	var atom = "data_" + icon
-	var dragEntries = []gtk.TargetEntry{NewTargetEntry(atom)}
 	var dragAtom = gdk.GdkAtomIntern(atom, false)
+	var dragEntries = []gtk.TargetEntry{
+		NewTargetEntry(atom, gtk.TARGET_SAME_APP, 0),
+	}
 
 	// Set the ID for Find().
 	dg.SetName(dg.ID())