#
#  Copyright 2017 Netflix, Inc.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#
from __future__ import print_function
import requests
import json
import logging
import sys
import socket
import warnings


hostname = socket.gethostname()


class BaseClient(object):
    printUrl = False
    headers = {'Content-Type': 'application/json', 'Accept': 'application/json'}

    def __init__(self, baseURL, baseResource, headers=None):
        self.baseURL = baseURL
        self.headers = self.mergeTwoDicts(self.headers, headers) if headers != None else self.headers
        self.baseResource = baseResource

    def get(self, resPath, queryParams=None):
        theUrl = "{}/{}".format(self.baseURL, resPath)
        resp = requests.get(theUrl, params=queryParams, headers=self.headers)
        self.__checkForSuccess(resp)
        if(resp.content == b''):
            return None
        else:
            return resp.json()

    def post(self, resPath, queryParams, body, headers=None):
        theUrl = "{}/{}".format(self.baseURL, resPath)
        theHeader = self.headers
        if headers is not None:
            theHeader = self.mergeTwoDicts(self.headers, headers)
        if body is not None:
            jsonBody = json.dumps(body, ensure_ascii=True)
            resp = requests.post(theUrl, params=queryParams, data=jsonBody, headers=theHeader)
        else:
            resp = requests.post(theUrl, params=queryParams, headers=theHeaders)

        self.__checkForSuccess(resp)
        return self.__return(resp, theHeader)

    def put(self, resPath, queryParams=None, body=None, headers=None):
        theUrl = "{}/{}".format(self.baseURL, resPath)
        theHeader = self.headers
        if headers is not None:
            theHeader = self.mergeTwoDicts(self.headers, headers)

        if body is not None:
            jsonBody = json.dumps(body, ensure_ascii=True)
            resp = requests.put(theUrl, params=queryParams, data=jsonBody, headers=theHeaders)
        else:
            resp = requests.put(theUrl, params=queryParams, headers=theHeaders)

        self.__print(resp)
        self.__checkForSuccess(resp)

    def delete(self, resPath, queryParams):
        theUrl = "{}/{}".format(self.baseURL, resPath)
        resp = requests.delete(theUrl, params=queryParams, headers=self.headers)
        self.__print(resp)
        self.__checkForSuccess(resp)

    def makeUrl(self, urlformat=None, *argv):
        url = self.baseResource + '/'
        if urlformat:
            url += urlformat.format(*argv)
        return url

    def makeParams(self, **kwargs):
        return dict((k, v) for k, v in kwargs.items() if v is not None) or None

    def mergeTwoDicts(self, x, y):
        z = x.copy()
        z.update(y)
        return z

    def __print(self, resp):
        if self.printUrl:
            print(resp.url)

    def __return(self, resp, header):
        retval = ''
        if len(resp.text) > 0:
            if header['Accept'] == 'text/plain':
                retval = resp.text
            elif header['Accept'] == 'application/json':
                retval = resp.json()
            else:
                retval = resp.text
        return retval

    def __checkForSuccess(self, resp):
        try:
            resp.raise_for_status()
        except requests.HTTPError:
            print("ERROR: " + resp.text)
            raise


class MetadataClient(BaseClient):
    BASE_RESOURCE = 'metadata'

    def __init__(self, baseURL, headers=None):
        BaseClient.__init__(self, baseURL, self.BASE_RESOURCE, headers)

    def getWorkflowDef(self, wfname, version=None):
        url = self.makeUrl('workflow/{}', wfname)
        return self.get(url, self.makeParams(version=version))

    def createWorkflowDef(self, wfdObj):
        url = self.makeUrl('workflow')
        return self.post(url, None, wfdObj)

    def updateWorkflowDefs(self, listOfWfdObj):
        url = self.makeUrl('workflow')
        self.put(url, None, listOfWfdObj)

    def getAllWorkflowDefs(self):
        url = self.makeUrl('workflow')
        return self.get(url)

    def unRegisterWorkflowDef(self, wfname, version):
        url = self.makeUrl("workflow/{name}/{version}".format(name=wfname, version=version))
        self.delete(url, None)

    def getTaskDef(self, tdName):
        url = self.makeUrl('taskdefs/{}', tdName)
        return self.get(url)

    def registerTaskDefs(self, listOfTaskDefObj):
        url = self.makeUrl('taskdefs')
        return self.post(url, None, listOfTaskDefObj)

    def registerTaskDef(self, taskDefObj):
        """registerTaskDef is deprecated since PUT /metadata/taskdefs does not
        register but updates a task definition. Use updateTaskDef function 
        instead.
        """
        warnings.warn(self.registerTaskDef.__doc__, DeprecationWarning)
        url = self.makeUrl('taskdefs')
        self.put(url, None, taskDefObj)

    def updateTaskDef(self, taskDefObj):
        url = self.makeUrl('taskdefs')
        self.put(url, None, taskDefObj)

    def unRegisterTaskDef(self, tdName, reason=None):
        url = self.makeUrl('taskdefs/{}', tdName)
        self.delete(url, self.makeParams(reason=reason))

    def getAllTaskDefs(self):
        url = self.makeUrl('taskdefs')
        return self.get(url)


class TaskClient(BaseClient):
    BASE_RESOURCE = 'tasks'

    def __init__(self, baseURL, headers=None):
        BaseClient.__init__(self, baseURL, self.BASE_RESOURCE, headers)

    def getTask(self, taskId):
        url = self.makeUrl('{}', taskId)
        return self.get(url)

    def updateTask(self, taskObj):
        url = self.makeUrl('')
        headers = {'Accept': 'text/plain; encodingcharset=utf-8'}
        self.post(url, None, taskObj, headers)

    def pollForTask(self, taskType, workerid, domain=None):
        url = self.makeUrl('poll/{}', taskType)
        params = {}
        params['workerid'] = workerid
        if domain is not None:
            params['domain'] = domain
        try:
            logging.getLogger("pyexec").debug("Polling at %s with %s", url, params)
            return self.get(url, params)
        except Exception as err:
            logging.getLogger("pyexec").debug('Error while polling %s', str(err))
            return None

    def pollForBatch(self, taskType, count, timeout, workerid, domain=None):
        url = self.makeUrl('poll/batch/{}', taskType)
        params = {}
        params['workerid'] = workerid
        params['count'] = count
        params['timeout'] = timeout

        if domain is not None:
            params['domain'] = domain

        try:
            return self.get(url, params)
        except Exception as err:
            print('Error while polling ' + str(err))
            return None

    def ackTask(self, taskId, workerid):
        #url = self.makeUrl('{}/ack', taskId)
        #params = {}
        #params['workerid'] = workerid
        #headers = {'Accept': 'application/json'}
        #value = self.post(url, params, None, headers)
        #return value in ['true', True]
        return True

    def getTasksInQueue(self, taskName):
        url = self.makeUrl('queue/{}', taskName)
        return self.get(url)

    def removeTaskFromQueue(self, taskId, reason=None):
        url = self.makeUrl('queue/{}', taskId)
        params = {}
        params['reason'] = reason
        self.delete(url, params)

    def getTaskQueueSizes(self, listOfTaskName):
        url = self.makeUrl('queue/sizes')
        return self.post(url, None, listOfTaskName)


class WorkflowClient(BaseClient):
    BASE_RESOURCE = 'workflow'

    def __init__(self, baseURL, headers=None):
        BaseClient.__init__(self, baseURL, self.BASE_RESOURCE, headers)

    def getWorkflow(self, wfId, includeTasks=True):
        url = self.makeUrl('{}', wfId)
        params = {}
        params['includeTasks'] = includeTasks
        return self.get(url, params)

    def getRunningWorkflows(self, wfName, version=None, startTime=None, endTime=None):
        url = self.makeUrl('running/{}', wfName)
        params = {}
        params['version'] = version
        params['startTime'] = startTime
        params['endTime'] = endTime
        return self.get(url, params)

    def startWorkflow(self, wfName, inputjson, version=None, correlationId=None):
        url = self.makeUrl('{}', wfName)
        params = {}
        params['version'] = version
        params['correlationId'] = correlationId
        headers = {'Accept': 'text/plain'}
        return self.post(url, params, inputjson, headers)

    def terminateWorkflow(self, wfId, reason=None):
        url = self.makeUrl('{}', wfId)
        params = {}
        params['reason'] = reason
        self.delete(url, params)

    def removeWorkflow(self, wfId, archiveWorkflow, reason=None):
        url = self.makeUrl('{}/remove', wfId)
        self.delete(url, self.makeParams(archiveWorkflow=archiveWorkflow, reason=reason))

    def pauseWorkflow(self, wfId):
        url = self.makeUrl('{}/pause', wfId)
        self.put(url)

    def resumeWorkflow(self, wfId):
        url = self.makeUrl('{}/resume', wfId)
        self.put(url)

    def skipTaskFromWorkflow(self, wfId, taskRefName, skipTaskRequest):
        url = self.makeUrl('{}/skiptask/{}', wfId, taskRefName)
        self.post(url, None, skipTaskRequest)

    def rerunWorkflow(self, wfId, taskRefName, rerunWorkflowRequest):
        url = self.makeUrl('{}/rerun', wfId)
        return self.post(url, None, rerunWorkflowRequest)

    def restartWorkflow(self, wfId, taskRefName, fromTaskRef):
        url = self.makeUrl('{}/restart', wfId)
        params = {}
        params['from'] = fromTaskRef
        self.post(url, params, None)

class EventServicesClient(BaseClient):
    BASE_RESOURCE = 'event'

    def __init__(self, baseURL, headers = None):
        BaseClient.__init__(self, baseURL, self.BASE_RESOURCE, headers)

    def getEventHandlerDef(self, event, activeOnly=True):
        url = self.makeUrl('{}', event)
        params = {}
        params['activeOnly'] = activeOnly
        return self.get(url, params)

    def getEventHandlerDefs(self):
        url = self.makeUrl()
        return self.get(url)

    def createEventHandlerDef(self, ehObj):
        url = self.makeUrl()
        return self.post(url, None, ehObj)

    def updateEventHandlerDef(self, ehObj):
        url = self.makeUrl()
        return self.put(url, None, ehObj)

    def removeEventHandler(self, ehName):
        url = self.makeUrl('{}', ehName)
        self.delete(url, {})

    def getEventHandlerQueues(self):
        url = self.makeUrl('queues')
        return self.get(url)

    def getEventHandlerQueuesProviders(self):
        url = self.makeUrl('queues/providers')
        return self.get(url)

class WFClientMgr:
    def __init__(self, server_url='http://localhost:8080/api/', headers=None):
        self.workflowClient = WorkflowClient(server_url, headers)
        self.taskClient = TaskClient(server_url, headers)
        self.metadataClient = MetadataClient(server_url, headers)


def main():
    if len(sys.argv) < 3:
        print("Usage - python conductor server_url command parameters...")
        return None

    server_url = sys.argv[1]
    command = sys.argv[2]
    wfcMgr = WFClientMgr(server_url)
    wfc = wfcMgr.workflowClient
    if command == 'start':
        if len(sys.argv) < 7:
            print('python conductor server_url start workflow_name input_json [version] [correlationId]')
            return None
        wfName = sys.argv[3]
        input = json.loads(sys.argv[5])
        correlationId = sys.argv[6]
        workflowId = wfc.startWorkflow(wfName, input, 1, correlationId)
        print(workflowId)
        return workflowId
    elif command == 'get':
        if len(sys.argv) < 4:
            print('python conductor server_url get workflow_id')
            return None
        wfId = sys.argv[3]
        wfjson = wfc.getWorkflow(wfId)
        print(json.dumps(wfjson, indent=True, separators=(',', ': ')))
        return wfjson
    elif command == 'terminate':
        if len(sys.argv) < 4:
            print('python conductor server_url terminate workflow_id')
            return None
        wfId = sys.argv[3]
        wfc.terminateWorkflow(wfId)
        print('OK')
        return wfId


if __name__ == '__main__':
    main()