"""
This is ostensibly the place where Scripts specific code should live.
"""

import os
import shlex
import errno
import logging
import urlparse
import time
import errno

import wizard
from wizard import shell, util

def deploy_web(dir):
    # try the directory
    homedir, _, web_path = dir.partition("/web_scripts")
    if web_path:
        yield urlparse.ParseResult(
                "http",
                util.get_dir_owner(homedir) + ".scripts.mit.edu",
                web_path.rstrip('/'),
                "", "", "")
        yield urlparse.ParseResult(
                "http",
                "scripts.mit.edu",
                "/~" + util.get_dir_owner(homedir) + web_path.rstrip('/'),
                "", "", "")

def user_quota(dir=None):
    """
    Returns a tuple (quota usage, quota limit).  Works only for scripts
    servers.  Values are in KiB.  Returns ``(0, None)`` if we couldn't figure it out.
    """
    end = 2
    # sometimes the volume is busy; so we try several times
    for i in range(0, end + 1):
        try:
            return _user_quota(dir)
        except QuotaParseError as e:
            if i == end:
                raise e
            time.sleep(3) # give it a chance to unbusy
    assert False # should not get here

def _user_quota(dir=None):
    # XXX: The correct way is to implement Python modules implementing
    # bindings for all the appropriate interfaces
    unknown = (0, None)
    def parse_last_quote(ret):
        return ret.rstrip('\'').rpartition('\'')[2]
    if dir is None:
        dir = os.getcwd()
    sh = shell.Shell()
    try:
        cell = parse_last_quote(sh.eval("fs", "whichcell", "-path", dir))
    except shell.CallError:
        return unknown
    except OSError as e:
        if e.errno == errno.ENOENT:
            return unknown
        raise
    mount = None
    while dir:
        try:
            volume = parse_last_quote(sh.eval("fs", "lsmount", dir))[1:]
            break
        except shell.CallError:
            dir = os.path.dirname(dir)
        except OSError as e:
            if e.errno == errno.ENOENT:
                return unknown
            raise
    if not volume: return unknown
    try:
        result = sh.eval("vos", "examine", "-id", volume, "-cell", cell).splitlines()
    except OSError:
        try:
            result = sh.eval("/usr/sbin/vos", "examine", "-id", volume, "-cell", cell).splitlines()
        except OSError:
            return unknown
    except shell.CallError:
        return unknown
    try:
        usage = int(result[0].split()[3])
        limit = int(result[3].split()[1]) # XXX: FRAGILE
    except ValueError:
        raise QuotaParseError("vos examine output was:\n\n" + "\n".join(result))
    return (usage, limit)

class QuotaParseError(wizard.Error):
    """Could not parse quota information."""
    def __init__(self, msg):
        self.msg = msg
    def __str__(self):
        return """

ERROR: Could not parse quota. %s
""" % self.msg

def sql_auth(url):
    if url.driver == "mysql":
        try:
            url.host, url.username, url.password = shell.Shell().eval("/mit/scripts/sql/bin/get-password").split()
            return url
        except shell.CallError:
            pass
    return None