feat(attach): add OrgAttach:delete_one() and delete_all()

These correspond to the following Emacs functions:
- `org-attach-delete-one`
- `org-attach-delete-all`

Author: broken-pen

lua/orgmode/attach/core.lua

@@ -444,4 +444,57 @@ function AttachCore:open_in_vim(name, node)
   vim.cmd.edit(path)
 end
 
+---Delete a single attachment.
+---
+---@param node OrgAttachNode
+---@param name string the name of the attachment to delete
+---@return OrgPromise<nil>
+function AttachCore:delete_one(node, name)
+  if name == '' then
+    utils.echo_warning('No attachment selected')
+    return Promise.resolve()
+  end
+  local attach_dir = self:get_dir(node)
+  local path = vim.fs.joinpath(attach_dir, name)
+  return fileops.unlink(path):next(function()
+    return nil
+  end)
+end
+
+---Delete all attachments from the current outline node.
+---
+---This actually deletes the entire attachment directory. A safer way is to
+---open the directory with `reveal` and delete from there.
+---
+---@param node OrgAttachNode
+---@param recursive fun(): OrgPromise<boolean>
+---@return OrgPromise<string> deleted_dir
+function AttachCore:delete_all(node, recursive)
+  local attach_dir = self:get_dir(node)
+  -- A few synchronous FS operations here, can't really be avoided. The
+  -- alternative would be to evaluate `recursive` before it's necessary.
+  local uv = vim.uv or vim.loop
+  local ok, errmsg, err = uv.fs_unlink(attach_dir)
+  if ok then
+    return Promise.resolve()
+  elseif err ~= 'EISDIR' then
+    return Promise.reject(errmsg)
+  end
+  ok, errmsg, err = uv.fs_rmdir(attach_dir)
+  if ok then
+    return Promise.resolve()
+  elseif err ~= 'ENOTEMPTY' then
+    return Promise.reject(errmsg)
+  end
+  return recursive():next(function(do_recursive)
+    if not do_recursive then
+      return Promise.reject(errmsg)
+    end
+    return fileops.remove_directory(attach_dir, { recursive = true }):next(function()
+      node:remove_auto_tag()
+      return attach_dir
+    end)
+  end)
+end
+
 return AttachCore

lua/orgmode/attach/init.lua

@@ -107,6 +107,21 @@ function Attach:prompt()
       return self:reveal_nvim()
     end,
   })
+  menu:add_separator({ length = #menu.title })
+  menu:add_option({
+    label = 'Delete an attachment',
+    key = 'd',
+    action = function()
+      return self:delete_one()
+    end,
+  })
+  menu:add_option({
+    label = 'Delete all attachments.',
+    key = 'D',
+    action = function()
+      return self:delete_all()
+    end,
+  })
   menu:add_option({
     label = 'Set specific attachment directory for this task.',
     key = 's',
@@ -530,4 +545,48 @@ function Attach:open_in_vim(name, node)
     :wait(MAX_TIMEOUT)
 end
 
+---Delete a single attachment.
+---
+---@param name? string the name of the attachment to delete
+---@param node? OrgAttachNode
+---@return nil
+function Attach:delete_one(name, node)
+  node = node or self.core:get_current_node()
+  local attach_dir = self.core:get_dir(node)
+  return Promise.resolve(name or ui.select_attachment('Delete', attach_dir))
+    :next(function(chosen_name)
+      if not chosen_name then
+        return
+      end
+      return self.core:delete_one(node, chosen_name)
+    end)
+    :wait(MAX_TIMEOUT)
+end
+
+---Delete all attachments from the current outline node.
+---
+---This actually deletes the entire attachment directory. A safer way is to
+---open the directory with `reveal` and delete from there.
+---
+---@param force? boolean if true, delete directory will recursively deleted with no prompts.
+---@param node? OrgAttachNode
+---@return nil
+function Attach:delete_all(force, node)
+  node = node or self.core:get_current_node()
+  return Promise.resolve(force or ui.yes_or_no_or_cancel_slow('Remove all attachments? '))
+    :next(function(do_delete)
+      if not do_delete then
+        return Promise.reject('Cancelled')
+      end
+      return self.core:delete_all(node, function()
+        return Promise.resolve(force or ui.yes_or_no_or_cancel_slow('Recursive? '))
+      end)
+    end)
+    :next(function()
+      utils.echo_info('Attachment directory removed')
+      return nil
+    end)
+    :wait(MAX_TIMEOUT)
+end
+
 return Attach