import sys
import itertools
import jinja2
import re
import yaml
import os
from nested_lookup import nested_lookup

# pre-initialization get current working directory
cwd = os.getcwd()

# defines
SLOS_FOLDER_BASENAME = os.path.basename("slos")
OUTPUT_FOLDER_BASENAME = os.path.basename("output")
TEMPLATE_FOLDER_BASENAME = os.path.basename("templates")
TEMPLATE_FILES = {
    "terraform-template.j2":["builtin:service.keyRequest.errors.fivexx.rate"],
    "terraform-template-2.j2":["builtin:service.keyRequest.errors.server.successCount",
                               "builtin:service.keyRequest.count.server"],
    "terraform-template-3.j2":["builtin:service.keyRequest.errors.fivexx.count",
                               "builtin:service.keyRequest.count.server"],
    "terraform-template-4.j2":["builtin:service.successes.server.rate"],
    "terraform-template-5.j2":["calc:service.vehicleservice_oes_responsecode_998_requestcount",
                               "calc:service.vehicleservice_oes_responsecode_999_requestcount",
                               "calc:service.vehicleservice_oes_fivexx_count",
                               "calc:service.vehicleservice_oes_request_count_total"]
}

SLO_FILE_BASENAME = os.path.basename("TP_FTS-example.yaml")

# define entries
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 = []
metrics = {}
services = {}
keyRequests = {}

# methods
def logic(metrics,environment,TEMPLATE_FILES):
    for template,metric in TEMPLATE_FILES.items():
        print(set(metric))
        print(set(metrics[environment]))
        if set(metrics[environment]) == set(metric):
            return template,metric
        else:
            print("Lists do not match.")    

# read yaml file
with open(os.path.join(SLOS_FOLDER_BASENAME,SLO_FILE_BASENAME)) as f:
    slos = list(yaml.safe_load_all(f))

# fill values
for i,slo in enumerate(slos):
    slo_id = slo["slo_id"]
    slo_name = slo["slo_name"]
    module_name = re.sub(r'[^a-zA-Z ]+', '', slo_name).replace(' ', '_').replace('__', '_')
    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 j,environment in enumerate(slo["slo_definition"]):
        environments.append(environment)
        metrics[environment] = nested_lookup('metric',slo["slo_definition"][environment])
        services[environment] = '~",\n\t\t\t\t~"'.join(nested_lookup('service',slo["slo_definition"][environment]))
        keyRequests[environment] = nested_lookup('keyRequests',slo["slo_definition"][environment])
        keyRequests[environment] = '~",\n\t\t\t\t~"'.join(itertools.chain.from_iterable(keyRequests[environment]))
    environment = None

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

# create template file
for e,environment in enumerate(environments):
    folder_path = os.path.join(cwd,OUTPUT_FOLDER_BASENAME,environment.replace('-','_'),"slo")
    if not os.path.exists(folder_path):
        os.makedirs(folder_path)
    with open(os.path.join(folder_path,module_name+".yaml"),"w+") as file:
        t,m = logic(metrics,environment,TEMPLATE_FILES)
        jinja_template = jinja_environment.get_template(t)
        file.write(jinja_template.render(module=module_name,
                                         slo_name=slo_name,
                                         metric=m[0],
                                         metricA=m[0],
                                         metricB=m[1],
                                         metricC=m[2],
                                         metricD=m[3],
                                         description=description,
                                         service=services[environment],
                                         keyRequest=keyRequests[environment],
                                         target=slo_definition_tresholds_failure,
                                         warning=slo_definition_tresholds_warning))