#!/usr/bin/env python3
""" Parse json file generated by pytest benchmarks and create htm report file
    for files exceeding expected threshold print information to the console
"""

import os
from sys import exit
from json import dumps, load

def get_request_from_yaml(path_to_yaml):
    """ Extract request parameters from given yaml file
    Parameters:
    - path_to_yaml - path to yaml file
    Returns:
    - string with request parameters
    """
    import yaml
    yaml_document = None
    with open(path_to_yaml, "r") as yaml_file:
        yaml_document = yaml.load(yaml_file, Loader=yaml.BaseLoader)
    if "stages" in yaml_document:
        if "request" in yaml_document["stages"][0]:
            json_parameters = yaml_document["stages"][0]["request"].get("json", None)
            assert json_parameters is not None, "Unable to find json parameters in request"
            return dumps(json_parameters)
    return ""

def make_class_path_dict(root_dir):
    """ Scan root dir for files with given pattern and construct dictionary
    with keys as path with replaced ., -, / characters and values as file path
    Parameters:
    - root_dir - dir to scan for files
    Returns:
    - dict class_name -> path
    """
    from fnmatch import fnmatch

    pattern = "*.tavern.yaml"

    ret = {}

    for path, _, files in os.walk(root_dir):
        for name in files:
            if fnmatch(name, pattern):
                test_path = os.path.join(path, name)
                ret[test_path.replace(".", "_").replace("-", "_").replace("/", "_")] = test_path
    return ret

def class_to_path(class_name, class_to_path_dic):
    """ Return path to test file basing on class name
    Parameters:
    - class_name - test to find,
    - class_to_path_dic - dict with class -> path key/values
    Return:
    - path to test file
    """
    from fnmatch import fnmatch
    for c, p in class_to_path_dic.items():
        if fnmatch(c, "*" + class_name):
            return p
    return None

def json_report_parser(path_to_test_dir, json_file, time_threshold=1.0):
    above_treshold = []
    html_file, _ = os.path.splitext(json_file)
    html_file = "tavern_report_" + html_file + ".html"
    class_to_path_dic = make_class_path_dict(path_to_test_dir)
    with open(html_file, "w") as ofile:
        ofile.write("<html>\n")
        ofile.write("  <head>\n")
        ofile.write("    <style>\n")
        ofile.write("      table, th, td {\n")
        ofile.write("        border: 1px solid black;\n")
        ofile.write("        border-collapse: collapse;\n")
        ofile.write("      }\n")
        ofile.write("      th, td {\n")
        ofile.write("        padding: 15px;\n")
        ofile.write("      }\n")
        ofile.write("    </style>\n")
        ofile.write("  </head>\n")
        ofile.write("  <body>\n")
        ofile.write("    <table>\n")
        ofile.write("      <tr><th>Test name</th><th>Min time [ms]</th><th>Max time [ms]</th><th>Mean time [ms]</th></tr>\n")
        json_data = None
        with open(json_file, "r") as json_file:
            json_data = load(json_file)
        for benchmark in json_data['benchmarks']:
            if float(benchmark['stats']['mean']) > time_threshold:
                ofile.write("      <tr><td>{}<br/>Parameters: {}</td><td>{:.4f}</td><td>{:.4f}</td><td bgcolor=\"red\">{:.4f}</td></tr>\n".format(benchmark['name'], get_request_from_yaml(class_to_path(benchmark['name'][5:], class_to_path_dic)), benchmark['stats']['min'] * 1000, benchmark['stats']['max'] * 1000, benchmark['stats']['mean'] * 1000))
                above_treshold.append((benchmark['name'], "{:.4f}".format(benchmark['stats']['mean'] * 1000), get_request_from_yaml(class_to_path(benchmark['name'][5:], class_to_path_dic))))
            else:
                ofile.write("      <tr><td>{}</td><td>{:.4f}</td><td>{:.4f}</td><td>{:.4f}</td></tr>\n".format(benchmark['name'], benchmark['stats']['min'] * 1000, benchmark['stats']['max'] * 1000, benchmark['stats']['mean'] * 1000))
        ofile.write("    </table>\n")
        ofile.write("  </body>\n")
        ofile.write("</html>\n")
    return above_treshold

if __name__ == '__main__':
    import argparse
    parser = argparse.ArgumentParser()
    parser.add_argument("path_to_test_dir", type = str, help = "Path to test directory for given json benchmark file")
    parser.add_argument("json_file", type = str, help = "Path to benchmark json file")
    parser.add_argument("--time-threshold", dest="time_threshold", type=float, default=1.0, help="Time threshold for test execution time, tests with execution time greater than threshold will be marked on red.")
    args = parser.parse_args()

    if not json_report_parser(args.path_to_test_dir, args.json_file, args.time_threshold):
        exit(1)
    exit(0)

