opn

#!/usr/bin/env python3
import os, sys
import tty, termios
import fcntl, struct

COLOR_BLACK = "\033[30m"
COLOR_BG_CYAN = "\033[46m"
COLOR_RESET = "\033[0;0m"
CLEAR_LINE = "\033[K"

KEY_ESC = "\x1B"
KEY_RETURN = "\x0D"

def manual():
    print("Usage: opn [command ...] [keyword]")
    print("The last paramater will be used as [keyword] " +
          "for subdirectory searching.")
    print("[command ...] will be applied to the selected file.")

def search(keyword):
    result = []
    for (root, dirs, files) in os.walk("."):
        result_curdir = filter(lambda file: keyword in file, files)
        result += map(lambda x: os.path.join(root, x), result_curdir)

    return result

def get_terminal_size():
    th, tw, hp, wp = struct.unpack("HHHH", fcntl.ioctl(
            0, termios.TIOCGWINSZ, struct.pack("HHHH", 0, 0, 0, 0)))
    return (tw, th)

def print_files(l, pos, width, height):
    start = pos - int(height / 2);
    start = min(len(l) - height, start)
    start = max(0, start)
    end = start + min(len(l), height)

    for i in range(start, end):
        print(CLEAR_LINE, end = "")

        if i == pos:
            print(COLOR_BLACK + COLOR_BG_CYAN, end = "")

        print(l[i][:width], end = "")

        if i == pos:
            print(COLOR_RESET, end = "")

        print("")

def get_key():
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)

    try:
        tty.setraw(sys.stdin.fileno())
        return sys.stdin.read(1)
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)

def ui(l):
    width = get_terminal_size()[0]
    height = get_terminal_size()[1] - 1  # Leave a line for cursor
    pos = 0

    while True:
        print_files(l, pos, width, height)

        k = get_key()
        if   k == "k": pos -= 1
        elif k == "j": pos += 1
        elif k == "h": pos = max(0, pos - int(height / 2))
        elif k == "l": pos = min(len(l) - 1, pos + int(height / 2))
        elif k == "q" or k == KEY_ESC: break
        elif k == KEY_RETURN:
            run_command(l[pos])
            break;

        pos %= len(l)
        pos_moveup = min(len(l), height)
        print("\033[" + str(pos_moveup) + "A", end = "")

def run_command(s):
    cmds = sys.argv[1:-1] + ["\"" + s + "\""]
    os.system(" ".join(cmds))


try:
    if len(sys.argv) <= 1:
        manual()
        exit()

    result = search(sys.argv[-1])
    if len(result) <= 0:
        exit()

    ui(result)

except (KeyboardInterrupt, SystemExit):
    exit()