#!/usr/bin/env python3

import json
import logging
import os
import pathlib
import shutil
from datetime import datetime
from zipfile import ZipFile

import requests
from flask import Flask, request, render_template, send_file, after_this_request
from werkzeug.utils import secure_filename

from lib.render_job import RenderJob
from lib.render_queue import RenderQueue
from utilities.render_worker import RenderWorkerFactory, string_to_status

logger = logging.getLogger()
server = Flask(__name__)


@server.get('/api/jobs')
def jobs_json():
    return [x.json_safe_copy() for x in RenderQueue.job_queue]


@server.get('/api/jobs/<status_val>')
def filtered_jobs_json(status_val):
    state = string_to_status(status_val)
    jobs = [x.json_safe_copy() for x in RenderQueue.jobs_with_status(state)]
    if jobs:
        return jobs
    else:
        return f'Cannot find jobs with status {status_val}', 400


@server.get('/api/job_status/<job_id>')
def get_job_status(job_id):
    found_job = RenderQueue.job_with_id(job_id)
    if found_job:
        return found_job.json_safe_copy()
    else:
        return f'Cannot find job with ID {job_id}', 400


@server.get('/api/file_list/<job_id>')
def get_file_list(job_id):
    found_job = RenderQueue.job_with_id(job_id)
    if found_job:
        job_dir = os.path.dirname(found_job.worker.output_path)
        return os.listdir(job_dir)
    else:
        return f'Cannot find job with ID {job_id}', 400


@server.route('/api/download_all/<job_id>')
def download_all(job_id):

    zip_filename = None

    @after_this_request
    def clear_zip(response):
        if zip_filename and os.path.exists(zip_filename):
            os.remove(zip_filename)
        return response

    found_job = RenderQueue.job_with_id(job_id)
    if found_job:
        output_dir = os.path.dirname(found_job.worker.output_path)
        if os.path.exists(output_dir):
            zip_filename = pathlib.Path(found_job.worker.input_path).stem + '.zip'
            with ZipFile(zip_filename, 'w') as zipObj:
                for f in os.listdir(output_dir):
                    zipObj.write(filename=os.path.join(output_dir, f),
                                 arcname=os.path.basename(f))
            return send_file(zip_filename, mimetype="zip", as_attachment=True, )
        else:
            return f'Cannot find project files for job {job_id}', 500
    else:
        return f'Cannot find job with ID {job_id}', 400


@server.post('/api/register_client')
def register_client():
    client_hostname = request.values['hostname']
    x = RenderQueue.register_client(client_hostname)
    return "Success" if x else "Fail"


@server.post('/api/unregister_client')
def unregister_client():
    client_hostname = request.values['hostname']
    x = RenderQueue.unregister_client(client_hostname)
    return "Success" if x else "Fail"


@server.get('/api/clients')
def render_clients():
    return RenderQueue.render_clients


@server.get('/api/full_status')
def full_status():
    full_results = {'timestamp': datetime.now().isoformat(), 'servers': {}}

    try:
        for client_hostname in RenderQueue.render_clients:
            is_online = False
            if client_hostname == RenderQueue.host_name:
                snapshot_results = snapshot()
                is_online = True
            else:
                snapshot_results = {}
                try:
                    snapshot_request = requests.get(f'http://{client_hostname}:8080/snapshot', timeout=1)
                    snapshot_results = snapshot_request.json()
                    is_online = snapshot_request.ok
                except requests.ConnectionError as e:
                    pass
            server_data = {'status': snapshot_results.get('status', {}), 'jobs': snapshot_results.get('jobs', {}),
                           'is_online': is_online}
            full_results['servers'][client_hostname] = server_data
    except Exception as e:
        logger.error(f"Exception fetching full status: {e}")

    return full_results


@server.get('/api/snapshot')
def snapshot():
    server_status = RenderQueue.status()
    server_jobs = [x.json_safe_copy() for x in RenderQueue.job_queue]
    server_data = {'status': server_status, 'jobs': server_jobs, 'timestamp': datetime.now().isoformat()}
    return server_data


@server.post('/api/add_job')
def add_job_handler():

    try:
        """Create new job and add to server render queue"""
        if not request.form.get('json', None) and not request.is_json:
            return 'missing json data', 400

        # handle uploaded files
        uploaded_file = request.files.get('file', None)
        uploaded_file_local_path = None
        job_dir = None
        if uploaded_file and uploaded_file.filename:
            logger.info(f"Receiving uploaded file {uploaded_file.filename}")
            job_dir = os.path.join(server.config['UPLOAD_FOLDER'], (uploaded_file.filename + "_" +
                                                                    datetime.now().strftime("%Y.%m.%d_%H.%M.%S")))
            os.makedirs(job_dir, exist_ok=True)
            uploaded_file_local_path = os.path.join(job_dir, secure_filename(uploaded_file.filename))
            uploaded_file.save(uploaded_file_local_path)

        # convert job input paths for uploaded files and add jobs
        json_string = request.form.get('json', None)
        jobs_list = json.loads(json_string) if json_string else [request.json]
        results = []
        for job in jobs_list:
            if uploaded_file_local_path:
                job['input_path'] = uploaded_file_local_path
                output_dir = os.path.join(job_dir, job.get('name', None) or 'output')
                os.makedirs(output_dir, exist_ok=True)
                job['output_path'] = os.path.join(output_dir, os.path.basename(job['output_path']))
            remove_job_dir = len(jobs_list) == 1 and uploaded_file_local_path  # remove failed job dir for single file uploads only
            add_result = add_job(job, remove_job_dir_on_failure=remove_job_dir)
            results.append(add_result)

        # return any errors from results list
        for response in results:
            if response.get('error', None):
                if len(results) == 1:
                    return results, response.get('code', 500)
                else:
                    return results, 400
        return results

    except Exception as e:
        logger.exception(f"Unknown error adding job: {e}")
    return 'unknown error', 500


def add_job(job_params, remove_job_dir_on_failure=False):

    def remove_job_dir():
        if remove_job_dir_on_failure and job_dir and os.path.exists(job_dir):
            logger.debug(f"Removing job dir: {job_dir}")
            shutil.rmtree(job_dir)

    name = job_params.get("name", None)
    job_owner = job_params.get("owner", None)
    renderer = job_params.get("renderer", None)
    input_path = job_params.get("input_path", None)
    output_path = job_params.get("output_path", None)
    priority = int(job_params.get('priority', 2))
    args = job_params.get('args', {})
    client = job_params.get('client', RenderQueue.host_name)
    force_start = job_params.get('force_start', False)
    custom_id = None
    job_dir = None

    # check for minimum render requirements
    if None in [renderer, input_path, output_path]:
        err_msg = 'Cannot add job: Missing required parameters'
        logger.error(err_msg)
        return {'error': err_msg, 'code': 400}

    # local renders
    if client == RenderQueue.host_name:
        logger.info(f"Creating job locally - {name if name else input_path}")
        try:
            render_job = RenderJob(renderer, input_path, output_path, args, priority, job_owner, client,
                                   notify=False, custom_id=custom_id, name=name)
            RenderQueue.add_to_render_queue(render_job, force_start=force_start)
            return render_job.json_safe_copy()
        except Exception as e:
            err_msg = f"Error creating job: {str(e)}"
            logger.exception(err_msg)
            remove_job_dir()
            return {'error': err_msg, 'code': 400}

    # client renders
    elif client in RenderQueue.render_clients:

        # see if host is available
        if RenderQueue.is_client_available(client):

            # call uploader on remote client
            try:
                logger.info(f"Uploading file {input_path} to client {client}")
                job_data = request.json
                response = post_job_to_server(input_path, job_data, client)
                if response.ok:
                    logger.info("Job submitted successfully!")
                    return response.json() if response.json() else "Job ok"
                else:
                    remove_job_dir()
                    return {'error': "Job rejected by client", 'code': 400}
            except requests.ConnectionError as e:
                err_msg = f"Error submitting job to client: {client}"
                logger.error(err_msg)
                remove_job_dir()
                return {'error': err_msg, 'code': 500}
        else:
            # client is not available
            err_msg = f"Render client '{client}' is unreachable"
            logger.error(err_msg)
            remove_job_dir()
            return {'error': err_msg, 'code': 503}

    else:
        err_msg = f"Unknown render client: '{client}'"
        logger.error(err_msg)
        remove_job_dir()
        return {'error': err_msg, 'code': 400}


@server.get('/api/cancel_job')
def cancel_job():
    job_id = request.args.get('id', None)
    confirm = request.args.get('confirm', False)
    if not job_id:
        return 'job id not found', 400
    elif not confirm:
        return 'confirmation required', 400
    else:
        found = [x for x in RenderQueue.job_queue if x.id == job_id]
        if len(found) > 1:
            return f'multiple jobs found for ID {job_id}', 400
        elif found:
            success = RenderQueue.cancel_job(found[0])
            return success
    return 'job not found', 400


@server.get('/api/clear_history')
def clear_history():
    RenderQueue.clear_history()
    return 'success'


@server.route('/api/status')
def status():
    return RenderQueue.status()


@server.get('/api/renderer_info')
def renderer_info():
    renderer_data = {}
    for r in RenderWorkerFactory.supported_renderers():
        renderer_class = RenderWorkerFactory.class_for_name(r)
        renderer_data[r] = {'available': renderer_class.renderer_path() is not None,
                            'version': renderer_class.version(),
                            'supported_extensions': renderer_class.supported_extensions,
                            'supported_export_formats': renderer_class.supported_export_formats}
    return renderer_data


@server.route('/')
def default():
    return "Server running"


@server.route('/upload')
def upload_file_page():
    return render_template('upload.html', render_clients=RenderQueue.render_clients,
                           supported_renderers=RenderWorkerFactory.supported_renderers())


#todo: move this to a helper file
def post_job_to_server(input_path, job_list, client, server_port=8080):
    # Pack job data and submit to server
    job_files = {'file': (os.path.basename(input_path), open(input_path, 'rb'), 'application/octet-stream'),
                 'json': (None, json.dumps(job_list), 'application/json')}

    req = requests.post(f'http://{client}:{server_port}/api/add_job', files=job_files)
    return req