#!/usr/bin/env python3

import os
import sys
import neovim

try:
    nvim_socket = os.environ["NVIM"]
except KeyError:
    sys.stderr.write("Not inside Neovim terminal")
    sys.exit(1)

nvim = neovim.attach('socket', path=nvim_socket)


class GetReg:
    def name(self):
        return "getreg"

    def usage(self):
        return "[register]"

    def descr(self):
        return "Prints the contents of a Neovim register to stdout."

    def run(self, args):
        register = args[0]
        print(nvim.funcs.getreg(register))


class PutReg:
    def name(self):
        return "setreg"

    def usage(self):
        return "[register]"

    def descr(self):
        return "Puts the contents of stdin into a Neovim register."

    def run(self, args):
        register = args[0]
        lines = sys.stdin.read().splitlines()

        if len(lines) == 1:
            lines = lines[0]

        nvim.funcs.setreg(register, lines)


def print_help():
    sys.stderr.write("USAGE %s <command> [args...]\n" % sys.argv[0])
    sys.stderr.write("commands:\n")
    for c in commands:
        sys.stderr.write("\t%s: %s\n" % (c.name(), c.descr()))


commands = [GetReg(), PutReg()]

if len(sys.argv) < 2:
    print_help()
    sys.exit(1)

cmd = sys.argv[1]
args = sys.argv[2:]
for c in commands:
    if cmd == c.name():
        sys.exit(c.run(args) or 0)

sys.stderr.write("Unknown command %s\n" % cmd)
print_help()