textapi

type CellEditor interface {
	Edit(ctx context.Context, start, end term.Coordinates, str string) (
		from, to term.Coordinates, old string, err error,
	)
}

type CellView interface {
	RawCells() ([][]term.Cell, error)
}

type Command struct {
	Name string
	Args []string

	// optional. If command is dispatched while non-tab is in focus,
	// then these fields will be zero-valued.
	URI      workspaceapi.URI
	Resource Handler
	Window   browserapi.Window
	Cursor   struct {
		Content term.Coordinates
		Window  term.Coordinates
	}
}

type CommandHandler interface {
	// Handle is called when user issued a command previously
	// registered via SubscribeCommand.
	HandleCommand(context.Context, Command) (err error)

	// Complete takes command args and returns a list of expanded
	// options for them.
	// It also returns a expanded version of the last arg, or an
	// empty string if the last arg could/should not be
	// automatically expanded.
	Complete(ctx context.Context, cmd string, args []string) (
		iterator.Iterator[string], error,
	)
}

type CommandManual struct {
	Name string

	// Summary is a short 80-100 character description.
	Summary string

	// Synopsis is a single line synopsis of how
	// this CLI is to be used. It should ONLY include
	// the semantic information about how arguments are parsed.
	//
	// Example: [<options>] [<revision-range>] [[--] <path>...]
	Synopsis string

	// Commands is a list of accepted commands or nil
	// if no commands are expected.
	Commands []CommandManual
}

type CommandRegistry interface {
	// RegisterCommand registers a command to be dispatched
	// to CommandHandler. Registered commands appear in the
	// command prompt. Use RegisterCommand for editing and
	// live-programming actions that operate on the current
	// file and need no persistent output, such as
	// navigating to a symbol definition, toggling a fold, or
	// reformatting a selection.
	RegisterCommand(CommandManual, CommandHandler) error

	// RegisterREPLCommand registers a REPL command to be
	// dispatched to REPLHandler. Registered commands appear
	// in the IDE's shell. Use RegisterREPLCommand for
	// configuration, monitoring and troubleshooting commands
	// that produce inspectable output the user wants to
	// review, such as a debugger, a log viewer, or a status
	// dashboard.
	RegisterREPLCommand(CommandManual, REPLHandler) error
}

type Editor interface {
	// SubscribeEvents subscribes EventHandler to events of type EventType.
	SubscribeEvents([]EventType, EventHandler) error

	// Editor returns the editor.Handler that manages the given resource,
	// if there is a resource currently open with the given URI.
	Editor(resource workspaceapi.URI) (Handler, error)

	// SetLocationList sets the Handler's location list for users to
	// navigate the code. See LocationList for more details.
	// In order to remove a location list, SetLocationList must be called
	// with an empty (or nil) LocationList.
	// Locations are removed if underlying buffer is updated. It is the
	// responsibility of the caller to recompute the list of locations
	// and call SetLocationList with the new list of locations after
	// every update. Check cell.Buffer.Subscribe for more details.
	SetLocationList(Handler, LocationPriority, string, LocationList) error

	// Moves cursor to the next location on list with ID.
	MoveToNextLocation(h Handler, ID string) error

	// Moves cursor to the previous location on list with ID.
	MoveToPrevLocation(h Handler, ID string) error

	// Cursor gets the position of Handler's cursor in the underlying
	// content buffer.
	Cursor(Handler) (term.Coordinates, error)

	// SetCursor sets the cursor of Handler to the given Coordinates.
	SetCursor(Handler, term.Coordinates) error

	// CellView returns a CellView which allows to read the editor's internal buffer.
	CellView(Handler) CellView

	// CellEditor returns a CellEditor which allows for direct write access
	// to the editor's internal buffer.
	CellEditor(Handler) CellEditor

	// SetDefaultAttributes sets the default attributes of the given Handler
	// before any LocationList overwrites.
	SetDefaultAttributes(Handler, term.Attributes) error
}

type Event struct {
	Type     EventType
	URI      workspaceapi.URI
	Resource Handler

	Start, End term.Coordinates
	From, To   term.Coordinates
	Content    string
}

type EventHandler interface {
	// Handle handles Event and returns true if it no longer needs to receive events,
	// in other words it returns true if it's done processing events.
	Handle(context.Context, Event) bool
}

type EventType uint8

type Handler interface {
	browserapi.Handler

	// This is only used to differentiate editor.Handler from the rest
	// of tui.Handler in a browser.Component.
	Resource() workspaceapi.URI
}

type Location struct {
	From, To term.Coordinates
	Attr     term.Attributes
	Message  string
	Icon     string
}

type LocationList interface {
	Current() (Location, bool)
	Prev() (Location, bool)
	Next() (Location, bool)
}

type LocationPriority uint

type REPLHandler interface {
	repl.CommandHandler

	// Help returns responsive components that describe
	// the command's usage for the given arguments.
	Help(ctx context.Context, args []string) (
		iterator.Iterator[component.Responsive], error,
	)
}