import abc
import time
import socket
import random
import os.path
import logging
import datetime

from paramiko import SSHException

from wally.utils import ssize_to_b, open_for_append_or_create, sec_to_str

from wally.ssh_utils import (copy_paths, run_over_ssh,
                             save_to_remote, ssh_mkdir,
                             # delete_file,
                             connect, read_from_remote, Local)

from . import postgres
from .io import agent as io_agent
from .io import formatter as io_formatter
from .io.results_loader import parse_output


logger = logging.getLogger("wally")


class IPerfTest(object):
    def __init__(self, on_result_cb, test_uuid, node,
                 log_directory=None,
                 coordination_queue=None,
                 remote_dir="/tmp/wally"):
        self.on_result_cb = on_result_cb
        self.log_directory = log_directory
        self.node = node
        self.test_uuid = test_uuid
        self.coordination_queue = coordination_queue
        self.remote_dir = remote_dir

    def join_remote(self, path):
        return os.path.join(self.remote_dir, path)

    def coordinate(self, data):
        if self.coordination_queue is not None:
            self.coordination_queue.put(data)

    def pre_run(self):
        pass

    def cleanup(self):
        pass

    @abc.abstractmethod
    def run(self, barrier):
        pass

    @classmethod
    def format_for_console(cls, data):
        msg = "{0}.format_for_console".format(cls.__name__)
        raise NotImplementedError(msg)

    def run_over_ssh(self, cmd, **kwargs):
        return run_over_ssh(self.node.connection, cmd,
                            node=self.node.get_conn_id(), **kwargs)

    @classmethod
    def coordination_th(cls, coord_q, barrier, num_threads):
        pass


class TwoScriptTest(IPerfTest):
    def __init__(self, opts, *dt, **mp):
        IPerfTest.__init__(self, *dt, **mp)
        self.opts = opts

        if 'run_script' in self.opts:
            self.run_script = self.opts['run_script']
            self.prepare_script = self.opts['prepare_script']

    def get_remote_for_script(self, script):
        return os.path.join(self.tmp_dir, script.rpartition('/')[2])

    def copy_script(self, src):
        remote_path = self.get_remote_for_script(src)
        copy_paths(self.node.connection, {src: remote_path})
        return remote_path

    def pre_run(self):
        remote_script = self.copy_script(self.node.connection,
                                         self.pre_run_script)
        cmd = remote_script
        self.run_over_ssh(cmd)

    def run(self, barrier):
        remote_script = self.copy_script(self.node.connection, self.run_script)
        cmd_opts = ' '.join(["%s %s" % (key, val) for key, val
                             in self.opts.items()])
        cmd = remote_script + ' ' + cmd_opts
        out_err = self.run_over_ssh(cmd)
        self.on_result(out_err, cmd)

    def parse_results(self, out):
        for line in out.split("\n"):
            key, separator, value = line.partition(":")
            if key and value:
                self.on_result_cb((key, float(value)))

    def on_result(self, out_err, cmd):
        try:
            self.parse_results(out_err)
        except Exception as exc:
            msg_templ = "Error during postprocessing results: {0!s}. {1}"
            raise RuntimeError(msg_templ.format(exc, out_err))


class PgBenchTest(TwoScriptTest):
    root = os.path.dirname(postgres.__file__)
    prepare_script = os.path.join(root, "prepare.sh")
    run_script = os.path.join(root, "run.sh")


class IOPerfTest(IPerfTest):

    def __init__(self, test_options, *dt, **mp):
        IPerfTest.__init__(self, *dt, **mp)
        self.options = test_options
        self.config_fname = test_options['cfg']
        self.alive_check_interval = test_options.get('alive_check_interval')
        self.config_params = test_options.get('params', {})
        self.tool = test_options.get('tool', 'fio')
        self.raw_cfg = open(self.config_fname).read()
        self.configs = list(io_agent.parse_all_in_1(self.raw_cfg,
                                                    self.config_params))

        cmd_log = os.path.join(self.log_directory, "task_compiled.cfg")
        raw_res = os.path.join(self.log_directory, "raw_results.txt")

        self.io_py_remote = self.join_remote("agent.py")
        self.log_fl = self.join_remote("log.txt")
        self.pid_file = self.join_remote("pid")
        self.task_file = self.join_remote("task.cfg")

        fio_command_file = open_for_append_or_create(cmd_log)

        cfg_s_it = io_agent.compile_all_in_1(self.raw_cfg, self.config_params)
        splitter = "\n\n" + "-" * 60 + "\n\n"
        fio_command_file.write(splitter.join(cfg_s_it))
        self.fio_raw_results_file = open_for_append_or_create(raw_res)

    def cleanup(self):
        # delete_file(conn, self.io_py_remote)
        # Need to remove tempo files, used for testing
        pass

    def prefill_test_files(self):
        files = {}

        for section in self.configs:
            sz = ssize_to_b(section.vals['size'])
            msz = sz / (1024 ** 2)

            if sz % (1024 ** 2) != 0:
                msz += 1

            fname = section.vals['filename']

            # if already has other test with the same file name
            # take largest size
            files[fname] = max(files.get(fname, 0), msz)

        cmd_templ = "dd oflag=direct " + \
                    "if=/dev/zero of={0} bs={1} count={2}"

        if self.options.get("use_sudo", True):
            cmd_templ = "sudo " + cmd_templ

        ssize = 0
        stime = time.time()

        for fname, curr_sz in files.items():
            cmd = cmd_templ.format(fname, 1024 ** 2, curr_sz)
            ssize += curr_sz
            self.run_over_ssh(cmd, timeout=curr_sz)

        ddtime = time.time() - stime
        if ddtime > 1E-3:
            fill_bw = int(ssize / ddtime)
            mess = "Initiall dd fill bw is {0} MiBps for this vm"
            logger.info(mess.format(fill_bw))

    def install_utils(self, max_retry=3, timeout=5):
        need_install = []
        for bin_name, package in (('fio', 'fio'), ('screen', 'screen')):
            try:
                self.run_over_ssh('which ' + bin_name, nolog=True)
            except OSError:
                need_install.append(package)

        cmd = "sudo apt-get -y install " + " ".join(need_install)

        for i in range(max_retry):
            try:
                self.run_over_ssh(cmd)
                break
            except OSError as err:
                time.sleep(timeout)
        else:
            raise OSError("Can't install - " + str(err))

    def pre_run(self):
        with self.node.connection.open_sftp() as sftp:
            ssh_mkdir(sftp, self.remote_dir, intermediate=True)

        self.install_utils()

        local_fname = os.path.splitext(io_agent.__file__)[0] + ".py"
        files_to_copy = {local_fname: self.io_py_remote}
        copy_paths(self.node.connection, files_to_copy)

        if self.options.get('prefill_files', True):
            self.prefill_test_files()
        else:
            logger.warning("Prefilling of test files is disabled")

    def run(self, barrier):
        cmd_templ = "screen -S {screen_name} -d -m " + \
                    "env python2 {0} -p {pid_file} -o {results_file} " + \
                    "--type {1} {2} --json {3}"

        if self.options.get("use_sudo", True):
            cmd_templ = "sudo " + cmd_templ

        params = " ".join("{0}={1}".format(k, v)
                          for k, v in self.config_params.items())

        if "" != params:
            params = "--params " + params

        with self.node.connection.open_sftp() as sftp:
            save_to_remote(sftp,
                           self.task_file, self.raw_cfg)

        screen_name = self.test_uuid
        cmd = cmd_templ.format(self.io_py_remote,
                               self.tool,
                               params,
                               self.task_file,
                               pid_file=self.pid_file,
                               results_file=self.log_fl,
                               screen_name=screen_name)
        logger.debug("Waiting on barrier")

        exec_time = io_agent.calculate_execution_time(self.configs)
        exec_time_str = sec_to_str(exec_time)

        try:
            timeout = int(exec_time * 2 + 300)
            if barrier.wait():
                templ = "Test should takes about {0}." + \
                        " Should finish at {1}," + \
                        " will wait at most till {2}"
                now_dt = datetime.datetime.now()
                end_dt = now_dt + datetime.timedelta(0, exec_time)
                wait_till = now_dt + datetime.timedelta(0, timeout)

                logger.info(templ.format(exec_time_str,
                                         end_dt.strftime("%H:%M:%S"),
                                         wait_till.strftime("%H:%M:%S")))

            self.run_over_ssh(cmd)
            logger.debug("Test started in screen {0}".format(screen_name))

            end_of_wait_time = timeout + time.time()

            # time_till_check = random.randint(30, 90)
            time_till_check = 1

            pid = None
            no_pid_file = True
            tcp_conn_timeout = 30
            pid_get_timeout = 30 + time.time()
            connection_ok = True

            # TODO: add monitoring socket
            if self.node.connection is not Local:
                self.node.connection.close()

            conn_id = self.node.get_conn_id()

            while end_of_wait_time > time.time():
                conn = None
                time.sleep(time_till_check)

                try:
                    if self.node.connection is not Local:
                        conn = connect(self.node.conn_url,
                                       conn_timeout=tcp_conn_timeout)
                    else:
                        conn = self.node.connection

                    try:
                        with conn.open_sftp() as sftp:
                            try:
                                pid = read_from_remote(sftp, self.pid_file)
                                no_pid_file = False
                            except (NameError, IOError):
                                no_pid_file = True
                    finally:
                        if conn is not Local:
                            conn.close()
                            conn = None

                    if no_pid_file:
                        if pid is None:
                            if time.time() > pid_get_timeout:
                                msg = ("On node {0} pid file doesn't " +
                                       "appears in time")
                                logger.error(msg.format(conn_id))
                                raise RuntimeError("Start timeout")
                        else:
                            # execution finished
                            break
                    if not connection_ok:
                        msg = "Connection with {0} is restored"
                        logger.debug(msg.format(conn_id))
                        connection_ok = True

                except (socket.error, SSHException, EOFError) as exc:
                    if connection_ok:
                        connection_ok = False
                        msg = "Lost connection with " + conn_id
                        msg += ". Error: " + str(exc)
                        logger.debug(msg)

            logger.debug("Done")

            if self.node.connection is not Local:
                timeout = tcp_conn_timeout * 3
                self.node.connection = connect(self.node.conn_url,
                                               conn_timeout=timeout)

            with self.node.connection.open_sftp() as sftp:
                # try to reboot and then connect
                out_err = read_from_remote(sftp,
                                           self.log_fl)
        finally:
            barrier.exit()

        self.on_result(out_err, cmd)

    def on_result(self, out_err, cmd):
        try:
            for data in parse_output(out_err):
                self.on_result_cb(data)
        except Exception as exc:
            msg_templ = "Error during postprocessing results: {0!s}"
            raise RuntimeError(msg_templ.format(exc))

    def merge_results(self, results):
        if len(results) == 0:
            return None

        merged_result = results[0]
        merged_data = merged_result['res']
        expected_keys = set(merged_data.keys())
        mergable_fields = ['bw', 'clat', 'iops', 'lat', 'slat']

        for res in results[1:]:
            assert res['__meta__'] == merged_result['__meta__']

            data = res['res']
            diff = set(data.keys()).symmetric_difference(expected_keys)

            msg = "Difference: {0}".format(",".join(diff))
            assert len(diff) == 0, msg

            for testname, test_data in data.items():
                res_test_data = merged_data[testname]

                diff = set(test_data.keys()).symmetric_difference(
                            res_test_data.keys())

                msg = "Difference: {0}".format(",".join(diff))
                assert len(diff) == 0, msg

                for k, v in test_data.items():
                    if k in mergable_fields:
                        res_test_data[k].extend(v)
                    else:
                        msg = "{0!r} != {1!r}".format(res_test_data[k], v)
                        assert res_test_data[k] == v, msg

        return merged_result

    @classmethod
    def format_for_console(cls, data):
        return io_formatter.format_results_for_console(data)