insert-layout: Add commands to turn insert layout on and off

Add two new commands, `InsertLayout` and `InsertLayoutOff`, which allow
us to activate a different keyboard layout for insert mode and restore
the previous layout when leaving insert wode.

Works reasonably well, but needs a bit of cleaning up now.

1 files changed, 89 insertions, 6 deletions

diff --git a/bundle/insert-layout/plugin/insert_layout.vim b/bundle/insert-layout/plugin/insert_layout.vim
index f271264..5ca3d7b 100644
--- a/bundle/insert-layout/plugin/insert_layout.vim
+++ b/bundle/insert-layout/plugin/insert_layout.vim
@@ -1,7 +1,90 @@
-" 2023.03.09
+vim9script
 
-augroup frinsert
-	autocmd!
-	autocmd InsertEnter * :call system('xkbswitch -se French-numerical')
-	autocmd InsertLeave * :call system('xkbswitch -se US')
-augroup END
+if exists('g:loaded_insert_layout')
+	finish
+endif
+g:loaded_insert_layout = 1
+
+const layout_names = {
+	us: 'US',
+	qwazerty: 'QWAZERTY2',
+	fr: 'French-numerical',
+	dvorak: 'Dvorak',
+}
+
+var normal_layout: string
+
+def IsLayoutSwitcherAvailable(): bool
+	return executable('xkbswitch')
+enddef
+
+def CurrentInputLayout(): string
+	return system('xkbswitch -ge')
+enddef
+
+def SetInputLayout(layout: string): void
+	system('xkbswitch -se ' .. layout)
+enddef
+
+def OnInsertEnter(layout: string): void
+	normal_layout = CurrentInputLayout()
+
+	SetInputLayout(layout)
+enddef
+
+def OnInsertLeave(): void
+	SetInputLayout(normal_layout)
+enddef
+
+def InsertLayoutOff(): void
+	# autocmd! insert_layout InsertEnter <buffer>
+	# autocmd! insert_layout InsertLeave <buffer>
+
+	autocmd_delete([
+		{
+			group: 'insert_layout',
+			event: 'InsertEnter',
+			bufnr: bufnr(),
+		},
+		{
+			group: 'insert_layout',
+			event: 'InsertLeave',
+			bufnr: bufnr(),
+		},
+	])
+enddef
+
+def InsertLayoutOn(layout: string): void
+	# InsertLayoutOff()
+
+	# autocmd insert_layout InsertEnter <buffer> OnInsertEnter(layout)
+	# autocmd insert_layout InsertLeave <buffer> OnInsertLeave()
+	autocmd_add([
+		{
+			replace: true,
+			group: 'insert_layout',
+			event: 'InsertEnter',
+			bufnr: bufnr(),
+			cmd: 'OnInsertEnter("' .. layout_names[layout] .. '")',
+		},
+		{
+			replace: true,
+			group: 'insert_layout',
+			event: 'InsertLeave',
+			bufnr: bufnr(),
+			cmd: 'OnInsertLeave()',
+		},
+	])
+enddef
+
+# TODO: Add layout completion
+command! -nargs=1 InsertLayout InsertLayoutOn(<q-args>)
+command! InsertLayoutOff InsertLayoutOff()
+
+# SetInputLayout(layout_names['fr'])
+
+# augroup frinsert
+# 	autocmd!
+# 	autocmd InsertEnter * :call system('xkbswitch -se French-numerical')
+# 	autocmd InsertLeave * :call system('xkbswitch -se US')
+# augroup END