TouhouGD/addons/resources_spreadsheet_view/text_editing_utils.gd

extends RefCounted

const non_typing_paragraph := "¶"
const non_typing_space := "●"
const whitespace_chars := [
    32, # " "
    44, # ","
    58, # ":"
    45, # "-"
    59, # ";"
    40, # "("
    41, # ")"
    46, # "."
    182, # "¶" Linefeed
    10, # "\n" Actual Linefeed
    967, # "●" Whitespace
]


static func is_character_whitespace(text : String, idx : int) -> bool:
    if idx <= 0: return true  # Stop at the edges.
    if idx >= text.length(): return true
    return text.unicode_at(idx) in whitespace_chars


static func show_non_typing(text : String) -> String:
    text = text\
        .replace(non_typing_paragraph, "\n")\
        .replace(non_typing_space, " ")
    
    if text.ends_with("\n"):
        text = text.left(text.length() - 1) + non_typing_paragraph

    elif text.ends_with(" "):
        text = text.left(text.length() - 1) + non_typing_space

    return text


static func revert_non_typing(text : String) -> String:
    if text.ends_with(non_typing_paragraph):
        text = text.left(text.length() - 1) + "\n"

    elif text.ends_with(non_typing_space):
        text = text.left(text.length() - 1) + " "

    return text


static func multi_erase_right(values : Array, cursor_positions : Array, ctrl_pressed : bool):
    for i in values.size():
        var start_pos = cursor_positions[i]
        cursor_positions[i] = _step_cursor(values[i], cursor_positions[i], 1, ctrl_pressed)

        cursor_positions[i] = min(
            cursor_positions[i], 
            values[i].length()
        )
        values[i] = (
            values[i].left(start_pos)
            + values[i].substr(cursor_positions[i])
        )
        cursor_positions[i] = start_pos

    return values


static func multi_erase_left(values : Array, cursor_positions : Array, ctrl_pressed : bool):
    for i in values.size():
        var start_pos = cursor_positions[i]

        cursor_positions[i] = _step_cursor(values[i], cursor_positions[i], -1, ctrl_pressed)
        values[i] = (
            values[i].substr(0, cursor_positions[i])
            + values[i].substr(start_pos)
        )

    return values


static func multi_move_left(values : Array, cursor_positions : Array, ctrl_pressed : bool):
    for i in cursor_positions.size():
        cursor_positions[i] = _step_cursor(values[i], cursor_positions[i], -1, ctrl_pressed)


static func multi_move_right(values : Array, cursor_positions : Array, ctrl_pressed : bool):
    for i in cursor_positions.size():
        cursor_positions[i] = _step_cursor(values[i], cursor_positions[i], 1, ctrl_pressed)


static func multi_paste(values : Array, cursor_positions : Array):
    var pasted_lines := DisplayServer.clipboard_get().replace("\r", "").split("\n")
    var paste_each_line := pasted_lines.size() == values.size()

    for i in values.size():
        if paste_each_line:
            cursor_positions[i] += pasted_lines[i].length()

        else:
            cursor_positions[i] += DisplayServer.clipboard_get().length()

        values[i] = (
            values[i].left(cursor_positions[i])
            + (pasted_lines[i] if paste_each_line else DisplayServer.clipboard_get())
            + values[i].substr(cursor_positions[i])
        )

    return values


static func multi_copy(values : Array):
    for i in values.size():
        values[i] = values[i]
    
    DisplayServer.clipboard_set("\n".join(values))


static func multi_input(input_char : String, values : Array, cursor_positions : Array):
    for i in values.size():
        values[i] = (
            values[i].left(cursor_positions[i])
            + input_char
            + values[i].substr(cursor_positions[i])
        )
        cursor_positions[i] = min(cursor_positions[i] + 1, values[i].length())

    return values


static func _step_cursor(text : String, start : int, step : int = 1, ctrl_pressed : bool = false) -> int:
    var cur := start
    if ctrl_pressed and is_character_whitespace(text, cur + step):
        cur += step

    while true:
        cur += step
        if !ctrl_pressed or is_character_whitespace(text, cur):
            if cur > text.length():
                return text.length()

            if cur <= 0:
                return 0

            if ctrl_pressed and step < 0:
                return cur + 1

            return cur

    return 0