from fide import *

global ctx
ctx = GlobalContext()

def cursor_go_left():
    buf = ctx.current_buffer
    cursor = ctx.current_buffer.cursor
    if cursor.col == 0:
        if cursor.line_num > 0:
            cursor.col = buf.lines[cursor.line_num-1].length
            cursor.want_col = cursor.col
            cursor.line_num -= 1
    else:
        cursor.col = max(0, cursor.col - 1)
        cursor.want_col = cursor.col

def cursor_go_right():
    buf = ctx.current_buffer
    cursor = ctx.current_buffer.cursor
    if cursor.col == buffer_line_len(buf):
        if cursor.line_num < buffer_total_lines(buf) - 1:
            cursor.col = 0
            cursor.want_col = cursor.col
            cursor.line_num += 1
    else:
        cursor.col = min(buffer_line_len(buf), cursor.col + 1)
        cursor.want_col = cursor.col

def cursor_go_down():
    buf = ctx.current_buffer
    cursor = ctx.current_buffer.cursor
    line_len = buffer_line_len(buf)
    cursor.line_num = min(len(buf.lines) - 1, cursor.line_num + 1)
    cursor.col = min(cursor.want_col, line_len)

def cursor_go_up():
    buf = ctx.current_buffer
    cursor = ctx.current_buffer.cursor
    cursor.line_num = max(0, cursor.line_num - 1)
    line_len = buffer_line_len(buf)
    # TODO: This should be global
    line_len = 20
    cursor.col = min(cursor.want_col, line_len)