import glob
import sys
import itertools
import jinja2
import re
import yaml
import os
from nested_lookup import nested_lookup
from pathlib import Path
import datetime

# defines
TEMPLATE_FOLDER_BASENAME = os.path.basename("jinja-templates")
TEMPLATE_FILES = {
    "terraform-template-1.j2":["builtin:service.keyRequest.errors.fivexx.rate"],
    "terraform-template-2.j2":["builtin:service.keyRequest.errors.server.successCount"],
    "terraform-template-3.j2":["builtin:service.keyRequest.errors.fivexx.count"],
    "terraform-template-4.j2":["builtin:service.errors.server.successCount"],
    "terraform-template-5.j2":["builtin:service.errors.fivexx.successCount"]
}
FOLDERS = {"My Journey":"DE-3",
           "Connected Vehicle Platforms":"DE-7",
           "My Life":"DE-4",
           "China Services":"EC-DE"}

# methods
def template_logic(metric):
    for template,metricElement in TEMPLATE_FILES.items():
        if all([item in metricElement for item in metric]):
        # if set(metricList) == set(metricTemplate):
            return template
    print("Problem occured while matching metric: Exiting program...")
    sys.exit(0)

# main
def main(configFile,output_path):
    slo_id = None
    slo_name = None
    module_name = None
    displayname = None
    department = None
    description = None
    doc_url = None
    slo_definition_tresholds_warning = None
    slo_definition_tresholds_failure = None
    environments = {}
    template = None
    metric = None
    services = []
    keyRequests = []

    try:
        # read yaml file
        with open(configFile) as cF:
            slos = list(yaml.safe_load_all(cF))
    except EnvironmentError:
        print('Corrupt yaml file:' + str(configFile))

    # fill values
    for slo in slos:
        slo_id = slo["slo_id"]
        slo_name = slo["slo_name"]
        module_name = slo_name
        displayname = slo["displayname"]
        description = slo["description"]
        department = slo["department"]
        doc_url = slo["doc_url"]
        slo_definition_tresholds_warning = slo["slo_definition"]["tresholds"]["warning"]
        slo_definition_tresholds_failure = slo["slo_definition"]["tresholds"]["failure"]
        slo["slo_definition"].pop("tresholds")

    for env in slo["slo_definition"]:
        if env in slo["slo_definition"]:
            environments[env] = slo["slo_definition"][env]

    # read template file
    jinja_environment = jinja2.Environment(loader=jinja2.FileSystemLoader(TEMPLATE_FOLDER_BASENAME),
                                           trim_blocks=True,
                                           lstrip_blocks=True)

    # generate terraform file
    for environment,ev in environments.items():
        folder_path = os.path.join(op,environment.replace('-','_'),"slo")
        # print("folder_path:",folder_path)
        if not os.path.exists(folder_path):
            os.makedirs(folder_path)
        metric = nested_lookup('metric',ev)
        
        for service in ev[0]["filter"]:
            services.append(nested_lookup('service',service))
            keyRequests.append(nested_lookup('keyRequests',service))

        with open(os.path.join(folder_path,module_name+".tf"),"w+") as file:
            jinja_template = jinja_environment.get_template(template_logic(metric))
            file.write(jinja_template.render(module=module_name,
                                             slo_name=slo_name,
                                             metric=metric[0],
                                             description=description,
                                             services='~",\n\t\t\t\t~"'.join(itertools.chain.from_iterable(services)),
                                             keyRequests='~",\n\t\t\t\t~"'.join(itertools.chain.from_iterable(itertools.chain.from_iterable(keyRequests))),
                                             target=slo_definition_tresholds_failure,
                                             warning=slo_definition_tresholds_warning))
        services = []
        keyRequests = []

if __name__ == "__main__":

    # pre-initialization get current working directory
    cwd = os.getcwd()
    OUTPUT_FOLDER_BASENAME = os.path.basename("output")

    if len(sys.argv) <= 1 or len(sys.argv) > 3:
        print(datetime.datetime.now(),".\generate.py <path to yaml folder> <optional:path to output folder>")
        print(datetime.datetime.now(),"Example: .\generate.py .\DE-3\ .\generated\\")
        print(datetime.datetime.now(),"Example: .\generate.py .\DE-3\,.\DE-4\,... .\generated\\")
        print(datetime.datetime.now(),"Missing input arguments. Exiting...")
        sys.exit()

    print(datetime.datetime.now(),"Script is running...")
    print(datetime.datetime.now(),"Current working directory:",cwd)
    print(datetime.datetime.now(),"Check arguments:",sys.argv)
    if len(sys.argv) == 3:
        op = sys.argv[2]
    else:
        op = OUTPUT_FOLDER_BASENAME

    # TESTING
    # for folderName,businessLine in FOLDERS.items():
    #     businessLinePath = os.path.join(businessLine)
    #     if not os.path.exists(businessLinePath):
    #         os.makedirs(businessLinePath)

    # for each folder
    arguments = sys.argv[1].split(',')
    for arg in arguments:
        pathname = os.path.join(arg)
        print(datetime.datetime.now(),"pathname:",pathname)
        # return path of slo config files
        configFiles = glob.glob(pathname=pathname + '/**/[TP_]*.yaml',
                               # root_dir=os.path.join(cwd,os.path.basename(arg)),
                                recursive=True)
        print(datetime.datetime.now(),"configFiles:",configFiles)

        # for each slo config file in folder
        for configFile in configFiles:
            print(datetime.datetime.now(),"Generating Terraform Files for:",configFile)
            main(configFile,op)
    print(datetime.datetime.now(),"Script finished.")