# tk_quick_indent.py

# tk_quick_indent.py ZZZ

from tkinter import *

root = Tk()
root.title('tk Quick-Indent')
root.geometry("1280x640+-10+0")

def default_indent(code, tabs=0, indent_char='\t'):
    def tab():
        tabbed_code.append(indent_char * tabs + line)

    keywordsA = "def class".split()
    keywordsB = "return continue break yield".split()
    lines = code.split("\n") + ['\n']
    tabbed_code = []
    prev = []
    for i in range(len(lines) - 1):
        line = lines[i].lstrip()
        if '#!t' in line: # custom indent
            tabs = int(line[line.index('#!t') + 3])
            tab()
        elif any(line.startswith(keyword) for keyword in keywordsA):
            tabs = 0
            tab()
            tabs = 1
        else:
            if line.endswith(':'):
                tab()
                tabs += 1
            elif any(line.startswith(keyword) for keyword in keywordsB):
                if lines[i + 1].strip():
                    tab()
                    tabs -= 1
                else:
                    tabs = 1
                    tab()
                    tabs = 0
            elif not lines[i + 1].strip():
                tab()
                tabs = 0
        if prev == tabbed_code:
            tab()
        prev = tabbed_code[:]
    tabbed_code = "\n".join(tabbed_code)
    return tabbed_code

frame = Frame(root)
frame.pack(fill=BOTH, expand=1)

textbox = Text(frame, height=40, width=140, wrap=WORD)
textbox.pack(fill=BOTH, expand=1)

# Add a scrollbar to the Text widget
scrollbar = Scrollbar(frame)
scrollbar.pack(side=RIGHT, fill=Y)
scrollbar.config(command=textbox.yview)
textbox.config(yscrollcommand=scrollbar.set)

untabbed_test_code = '''
def complex_operation(a, b, c):
try:
result = a / b
result = result ** c
result = result * (b + c)
return result
except ZeroDivisionError:
return "division by zero"
except TypeError as e:
if "unsupported operand type" in str(e):
return "unsupported operand type for operation"
else:
raise e

input_a = 10
input_b = 5
input_c = 2
output = complex_operation(input_a, input_b, input_c)
print("output:", output)

def calculate_result(data):
result = 0
for i in range(len(data)):
for j in range(i+1, len(data)):
sub_result = 0
for k in range(j, len(data)):
sub_result += data[k]
if sub_result == 0:
result += 1
return result

data = [1, -1, 2, 3, -2, -3, 4, -4]
output = calculate_result(data)
print("output:", output)
'''[1:-1]

test_code = default_indent(untabbed_test_code, tabs=0)

textbox.insert(INSERT, test_code)

line_numbers = ()

def select(event):
    global line_numbers
    sel = textbox.tag_ranges("sel")
    if not sel:
        return
    start_line, end_line = map(lambda x: int(str(x).split('.')[0]), sel)
    if start_line % 2 == 0:
        start_line += 1
    if end_line % 2 == 0:
        end_line -= 1
    line_numbers = range(start_line - 1, end_line)

def arrowkey_indent(event):
    if line_numbers and event.state == 262148:
        if "Left" in event.keysym:
            def f():
                if line.startswith('\t'):
                    return line[1:]
        elif "Right" in event.keysym:
            def f():
                return '\t' + line
        else:
            return
        for line_number in line_numbers:
            line = textbox.get(f"{line_number}.0", f"{line_number}.end")
            line = f()
            try:
                textbox.replace(f"{line_number}.0", f"{line_number}.end", line)
            except:
                0

textbox.bind("<KeyPress>", arrowkey_indent)
textbox.bind("<ButtonRelease-1>", select)
root.mainloop()