import urllib
import urllib2
import json
import random
from urllib2 import URLError
import sys

# Bind to the compiler
sys.path.append("../interface/HUTN")
from hutn_compiler.compiler import main as do_compile

# Helper functions and configuration: do not use yourself!
taskname = random.random()
address = None
last_output = None
mode = 0

def _input(value):
    # Ugly json encoding of primitives
    if isinstance(value, type([])):
        value = json.dumps(value)
        urllib2.urlopen(urllib2.Request(address, urllib.urlencode({"op": "set_input", "data": value, "taskname": taskname}))).read()
    else:
        value = json.dumps(value)
        urllib2.urlopen(urllib2.Request(address, urllib.urlencode({"op": "set_input", "value": value, "taskname": taskname}))).read()

def _input_raw(value, taskname):
    # Ugly json encoding of primitives
    urllib2.urlopen(urllib2.Request(address, urllib.urlencode({"op": "set_input", "value": value, "taskname": taskname}))).read()

def _compile_AL(code):
    # Compile an action language file and send the compiled code
    code_fragments = code.split("\n")
    code_fragments = [i for i in code_fragments if i.strip() != ""]
    code_fragments = [i.replace("    ", "\t") for i in code_fragments]
    initial_tabs = min([len(i) - len(i.lstrip("\t")) for i in code_fragments])
    code_fragments = [i[initial_tabs:] for i in code_fragments]
    code_fragments.append("")
    code = "\n".join(code_fragments)

    with open("__constraint.alc", "w") as f:
        f.write(code)
        f.flush()

    _input(do_compile("__constraint.alc", "../interface/HUTN/grammars/actionlanguage.g", "CS"))

def _compile_model(code):
    # Compile a model and send the compiled graph
    # First change multiple spaces to a tab
    code_fragments = code.split("\n")
    code_fragments = [i for i in code_fragments if i.strip() != ""]
    code_fragments = [i.replace("    ", "\t") for i in code_fragments]
    initial_tabs = min([len(i) - len(i.lstrip("\t")) for i in code_fragments])
    code_fragments = [i[initial_tabs:] for i in code_fragments]
    code_fragments.append("")
    code = "\n".join(code_fragments)

    with open("__model.mvc", "w") as f:
        f.write(code)
        f.flush()

    _input(do_compile("__model.mvc", "../interface/HUTN/grammars/modelling.g", "M") + ["exit"])

def _output():
    try:
        global last_output
        last_output = json.loads(urllib2.urlopen(urllib2.Request(address, urllib.urlencode({"op": "get_output", "taskname": taskname}))).read())
        return last_output
    except:
        raise UnknownError()

def _last_output():
    return last_output

def _consume_to_end():
    while (_output() not in ["Ready for command...", "Please give your command."]):
        pass

# Exceptions
class ModelverseException(Exception):
    pass

class UnknownError(ModelverseException):
    pass

class UnknownIdentifier(ModelverseException):
    pass

class UnknownType(ModelverseException):
    pass

class UnsupportedValue(ModelverseException):
    pass

class CompilationError(ModelverseException):
    pass

class NoSuchAttribute(ModelverseException):
    pass

class UnknownModel(ModelverseException):
    pass

class ConnectionError(ModelverseException):
    pass

class ModelExists(ModelverseException):
    pass

class PermissionDenied(ModelverseException):
    pass

class InvalidMode(ModelverseException):
    pass

# Main MvC operations
def init(address_param="http://localhost:8001"):
    """Starts up the connection to the Modelverse."""
    # return None
    # raises ConnectionError
    # raises UnknownError
    # raises InvalidMode
    global mode
    if mode != 0:
        raise InvalidMode()
    global address
    address = address_param
    try:
        _input_raw('"%s"' % taskname, "task_manager")
        mode = 1
    except URLError as e:
        raise ConnectionError(e.reason)

def login(username, password):
    """Log in an existing user."""
    # return None
    # raises UnknownError
    # raises PermissionDenied
    global mode
    if mode != 1:
        raise InvalidMode()
    _input(username)
    _input(password)
    _consume_to_end()
    mode = 2

def register(username, password):
    """Register a new user."""
    # return None
    # raises UnknownError
    # raises UserExists
    global mode
    if mode != 1:
        raise InvalidMode()
    _input(username)
    _input(password)
    _input(password)
    _consume_to_end()
    mode = 2

def model_add(model_name, metamodel_name, model_code):
    """Instantiate a new model."""
    # return None
    # raises UnknownModel
    # raises ModelExists
    # raises UnknownError
    # raises PermissionDenied
    # raises CompilationError
    if mode != 2:
        raise InvalidMode()
    _input("model_add")
    _output()
    _output()
    _input(metamodel_name)
    if _output() == "Model name?":
        _input(model_name)
        if _output() == "Waiting for model constructors...":
            try:
                _compile_model(model_code)
            except Exception:
                raise CompilationError()
            _consume_to_end()
        else:
            _consume_to_end()
            raise ModelExists()
    elif _last_output() == "Could not find type model!":
        _consume_to_end()
        raise UnknownModel()
    elif _last_output() == "Permission denied":
        _consume_to_end()
        raise PermissionDenied()

def model_modify(model_name):
    """Modify an existing model."""
    # return is_write
    # raises UnknownModel
    # raises PermissionDenied
    # raises UnknownError
    global mode
    if mode != 2:
        raise InvalidMode()

    _input("model_modify")
    _output()
    _input(model_name)
    if _output() == "Permission denied":
        _consume_to_end()
        raise PermissionDenied()
    elif _last_output() == "Could not find model!":
        _consume_to_end()
        raise UnknownModel()
    elif _last_output() == "Model loaded, ready for commands!":
        mode = 3
        if ("r/w" in _output()):
            write = True
        else:
            write = False
        _consume_to_end()
        return write
    else:
        _consume_to_end()
        raise UnknownException()

def model_list():
    """List all models."""
    # return [(model1, metamodel1), (model2, metamodel2), ...]
    # raises UnknownError
    if mode != 2:
        raise InvalidMode()
    _input("model_list")
    lst = []
    while (_output() != "Ready for command..."):
        v = _last_output()
        m, mm = v.split(":")
        m = m.strip()
        mm = mm.strip()
        lst.append((m, mm))
    return lst

def model_list_full():
    """List full information on all models."""
    # return [(model1, metamodel1, owner1, group1, permissions1), (model2, metamodel2, owner2, group2, permissions2), ...]
    # raises UnknownError
    if mode != 2:
        raise InvalidMode()
    _input("model_list_full")
    lst = []
    while (_output() != "Ready for command..."):
        v = _last_output()
        m, mm = v.split(":")
        m = m.strip()
        mm = mm.strip()
        perm, own, grp, m = m.split(" ")
        lst.append((m, mm, own, grp, perm))
    return lst

def model_overwrite(model_name, new_model):
    """Upload a new model and overwrite an existing model."""
    # return None
    # raises UnknownModel
    # raises PermissionDenied
    # raises CompilationError
    # raises UnknownError
    if mode != 2:
        raise InvalidMode()
    _input("model_overwrite")
    _input(model_name)
    _compile_model(new_model)

def user_logout():
    """Log out the current user. A new login will be required afterwards."""
    # return None
    # raises UnknownException
    global mode
    if mode != 2:
        raise InvalidMode()
    _input("exit")
    mode = 1

def user_delete():
    """Removes the current user. A new login will be required afterwards."""
    # return None
    # raises UnknownException
    global mode
    if mode != 2:
        raise InvalidMode()
    _input("self-destruct")
    mode = 1

# Actual operations on the model
def element_list():
    """Return a list of all IDs and the type of the element"""
    # return [(name1, type1), (name2, type2), ...]
    # raises UnknownError
    if mode != 3:
        raise InvalidMode()
    _input("list")
    lst = []
    _output()
    while (_output() != "Please give your command."):
        v = _last_output()
        m, mm = v.split(":")
        m = m.strip()
        mm = mm.strip()
        lst.append((m, mm))
    return lst

def types():
    """Return a list of all types usable in the model"""
    # return [type1, type2, ...]
    # raises UnknownError
    if mode != 3:
        raise InvalidMode()
    _input("types")
    _output()
    lst = []
    while (_output() != "Please give your command."):
        v = _last_output()
        m, mm = v.split(":")
        m = m.strip()
        lst.append(m)
    return lst

def read(ID):
    """Return a tuple of information on the element: its type and source/target (None if not an edge)"""
    # return (type, (source, target))
    # raises UnknownError
    # raises UnknownIdentifier
    if mode != 3:
        raise InvalidMode()
    _input("read")
    _output()
    _input(ID)
    _output()
    if _last_output() == "Unknown element; aborting":
        _consume_to_end()
        raise UnknownIdentifier()
    else:
        t = _output().split(":")[1].strip()
        if (not _output().startswith("Source:")):
            rval = (t, None)
        else:
            src = _last_output().split(":")[1].strip()
            trg = _output().split(":")[1].strip()
            rval = (t, (src, trg))
        while (_output() != "Please give your command."):
            pass
        return rval

def read_attrs(ID):
    """Return a dictionary of attribute value pairs"""
    # return {attr1: value1, attr2: value2, ...}
    # raises UnknownError
    # raises UnknownIdentifier
    if mode != 3:
        raise InvalidMode()
    _input("read")
    _output()
    _input(ID)
    _output()
    if _last_output() == "Unknown element; aborting":
        _consume_to_end()
        raise UnknownIdentifier()
    else:
        rval = {}
        while (_output() != "Attributes:"):
            pass
        while (_output() != "Please give your command."):
            r = _last_output()
            key, value = r.split(":")
            _, value = value.split("=")
            key = key.strip()
            value = value.strip()
            value = None if value == "None" else json.loads(value)
            rval[key] = value
        return rval

def instantiate(typename, edge=None, ID=""):
    """Create a new instance of the specified typename, between the selected elements (if not None), and with the provided ID (if any)"""
    # return instantiated_ID
    # raises UnknownError
    # raises UnknownType
    # raises UnknownIdentifier
    if mode != 3:
        raise InvalidMode()
    _input("instantiate")
    _input(typename)
    _input(ID)
    if (edge is not None):
        _input(edge[0])
        _input(edge[1])

def delete(ID):
    """Delete the element with the given ID"""
    # return None
    # raises UnknownError
    # raises UnknownIdentifier
    if mode != 3:
        raise InvalidMode()
    _input("delete")
    _input(ID)

def attr_assign(ID, attr, value):
    """Assign a value to an attribute"""
    # return None
    # raises UnknownError
    # raises UnknownIdentifier
    # raises NoSuchAttribute
    # raises UnsupportedValue
    if mode != 3:
        raise InvalidMode()
    _input("attr_modify")
    _input(ID)
    _input(attr)
    _input(value)

def attr_assign_code(ID, attr, code):
    """Assign a piece of Action Language code to the attribute"""
    # return None
    # raises UnknownError
    # raises UnknownIdentifier
    # raises NoSuchAttribute
    # raises UnsupportedValue
    if mode != 3:
        raise InvalidMode()
    _input("attr_modify")
    _input(ID)
    _input(attr)
    _compile_AL(code)

def upload(new_model):
    """Overwrite the current model with the provided model"""
    # return None
    # raises UnknownError
    # raises CompilationError
    if mode != 3:
        raise InvalidMode()
    _input("upload")
    _compile_model(new_model)

def read_outgoing(ID, typename):
    """Returns a list of all outgoing associations of a specific type ("" = all)"""
    # return [name1, name2, ...]
    # raises UnknownError
    # raises UnknownIdentifier
    # raises UnknownType
    if mode != 3:
        raise InvalidMode()
    _input("read_outgoing")
    _input(ID)
    _input(typename)
    lst = []
    while (_output() != "Please give your command."):
        lst.append(_last_output())
    return lst

def read_incoming(ID, typename):
    """Returns a list of all incoming associations of a specific type ("" = all)"""
    # return [name1, name2, ...]
    # raises UnknownError
    # raises UnknownIdentifier
    # raises UnknownType
    if mode != 3:
        raise InvalidMode()
    _input("read_incoming")
    _input(ID)
    _input(typename)
    lst = []
    while (_output() != "Please give your command."):
        lst.append(_last_output())
    return lst

def model_exit():
    """Leave model modify mode."""
    # return None
    # raises UnknownError
    global mode
    if mode != 3:
        raise InvalidMode()
    _input("exit")
    mode = 2

def transformation_add_MT_language():
    """Create a new Model Transformation language out of a set of metamodels."""
    raise NotImplementedError()

def transformation_add_MT():
    """Create a new model transformation."""
    raise NotImplementedError()

def transformation_add_AL():
    """Create a new action language fragment."""
    raise NotImplementedError()

def transformation_add_MANUAL():
    """Create a new manual model operation."""
    raise NotImplementedError()

def transformation_execute():
    """Execute an existing model operation."""
    raise NotImplementedError()

def transformation_list():
    """List existing model operations."""
    raise NotImplementedError()

def transformation_list_full():
    """List detailed information on model operations."""
    raise NotImplementedError()

def transformation_detail():
    """List full details of a a model operation."""
    raise NotImplementedError()

def transformation_RAMify():
    """Ramify an existing metamodel."""
    raise NotImplementedError()

def process_execute():
    """Execute a process model."""
    raise NotImplementedError()

def permission_modify():
    """Modify permissions of a model."""
    raise NotImplementedError()

def permission_owner():
    """Modify the owning user of a model."""
    raise NotImplementedError()

def permission_group():
    """Modify the owning group of a model."""
    raise NotImplementedError()

def group_create():
    """Create a new group."""
    raise NotImplementedError()

def group_delete():
    """Delete a group of which you are an owner."""
    raise NotImplementedError()

def group_owner_add():
    """Add a new owning user to a group you own."""
    raise NotImplementedError()

def group_owner_delete():
    """Delete an owning user to a group you own."""
    raise NotImplementedError()

def group_join():
    """Add a new user to a group you own."""
    raise NotImplementedError()

def group_kick():
    """Delete a user from a group you own."""
    raise NotImplementedError()

def group_list():
    """List existing groups."""
    raise NotImplementedError()

def admin_promote():
    """Promote a user to admin status."""
    raise NotImplementedError()

def admin_demote():
    """Demote a user from admin status."""
    raise NotImplementedError()