# tk_QuickCompare.py inspired by github's version

# tk_QuickCompare.py
# inspired by github's version

import tkinter as tk
from tkinter import messagebox

root = tk.Tk()
root.geometry("640x640+0+0")
root.title("QuickCompare")

text_area = tk.Text(root, wrap="none")
text_area.pack(expand=True, fill="both")

def update_colors():
    text_area.tag_configure("doc1_selected", background="white")
    text_area.tag_configure("doc2_not_selected", background="light green")
    text_area.tag_configure("doc1_removed", background="light pink")

    for i, tag in enumerate(selection_idx):
        text_area.tag_add(tag, f"{i + 1}.0", f"{i + 1}.end + 1c")

def paste_doc2():
    global selection_idx
    try:
        doc1_lines = text_area.get(1.0, tk.END).strip().split('\n')
        doc2_lines = root.clipboard_get().strip().split('\n')

        merged_lines = []
        selection_idx = []

        doc1_set = set(doc1_lines)
        doc2_set = set(doc2_lines)

        for line in doc1_lines:
            if line in doc2_set:
                merged_lines.append(line)
                selection_idx.append("doc1_selected")
            else:
                merged_lines.append(line)
                selection_idx.append("doc1_removed")

        doc2_index = 0
        for i, line in enumerate(merged_lines):
            while doc2_index < len(doc2_lines) and doc2_lines[doc2_index] not in doc1_set:
                merged_lines.insert(i, doc2_lines[doc2_index])
                selection_idx.insert(i, "doc2_not_selected")
                doc2_index += 1
                i += 1
            if doc2_index < len(doc2_lines) and doc2_lines[doc2_index] == line:
                doc2_index += 1

        while doc2_index < len(doc2_lines):
            merged_lines.append(doc2_lines[doc2_index])
            selection_idx.append("doc2_not_selected")
            doc2_index += 1

        text_area.delete(1.0, tk.END)
        text_area.insert(tk.END, '\n'.join(merged_lines))
        update_colors()
    except tk.TclError:
        messagebox.showerror("Error", "Clipboard Is Empty Or Not Accessible.")

# Demo
doc1 = """
print("Hello, World!")
x = 1
y = 2
z = x + y
print(z)
a = 3
b = 4
c = a + b
print(c)
# doc1
d = 5
e = 6
f = d + e
print(f)""".strip()

doc2 = """
# demo
print("Hello, World!")
x = 1
y = 2
z = x + y
print(z)
def bar():
    a = 3
    b = 4
    c = a + b
    print(c)
# doc1
# doc2
d = 5
e = 6
f = d + e
print(f)
bar()"""

text_area.delete(1.0, tk.END)
text_area.insert(tk.END, doc1)

root.clipboard_clear()
root.clipboard_append(doc2)

paste_button = tk.Button(root, text="Paste Doc2", command=paste_doc2)
paste_button.pack()

root.mainloop()