#!/usr/bin/python3
import json
import os
import pathlib
import platform
import pprint
import subprocess as sp
import sys
from shutil import copyfile

import psutil
from src.backend.lib.display import TerminalDisplay

log_file = "installer.log"
messages = []


class Configuration:
    def __init__(self):
        self._cp = pathlib.Path("config.json")
        self._data = self.open_file()
        self.system = platform.system()

    def open_file(self):
        """
        Try to open and then backup the configuration file.
        Fail and return false if initial configuration is not found.
        # TODO: More specific error handling
        """
        try:
            with open(str(self._cp), "r") as read_file:
                data = json.load(read_file)
            with open("config.backup.json", "w") as backup_file:
                json.dump(data, backup_file)
            return data
        except Exception as e:
            print(e)
            return False

    def write_file(self, data):
        """
        Write the provided data to the new configuration file
        """
        with open(str(self._cp), "w") as write_file:
            json.dump(data, write_file)
        return True


class RequiredServices:
    def check_ps(self, service_list):
        """
        Check service_list against running processes
        by calling self.process_list, remove found
        services from the list and return
        """
        # Get the matched processes
        _matches = self.process_list().intersection(set(service_list))
        for r in _matches:
            service_list.remove(r)
        return service_list

    @staticmethod
    def process_list():
        """
        Iterate running processes returning the name of each
        make it a set and return
        """
        _processes = []
        for p in psutil.process_iter():
            _processes.append(p.name())
        return set(_processes)

    @staticmethod
    def web_server_found(service_list):
        # Determine whether or not both possible webservers are missing
        _c = 0
        for r in service_list:
            if r == "nginx" or r == "httpd":
                _c = _c + 1
        if _c > 1:
            return False  # Return false if neither are found
        else:
            return True  # Return true if one is found

    @staticmethod
    def db_server_found(service_list):
        _c = 0
        for r in service_list:
            if r == "postgres":
                _c = _c + 1
        if _c > 0:
            return False
        else:
            return True


class SystemInstaller:
    def __init__(self):
        self.bin = self.get()
        self.site_dirs = ["/etc/nginx/sites-available", "/etc/nginx/sites-enabled"]
        self.nginx_conf = "pyshelf_nginx.conf"

    def get(self):
        platfrm = platform.platform().split("-")
        if platfrm[0].lower() == "linux":
            installers = [
                {"bin": "apt", "options": [], "search": "search", "install": "install"},
                {"bin": "pacman", "options": [], "search": "-Ss", "install": "-S"},
                {"bin": "yum", "options": [], "search": "search", "install": "install"},
                {"bin": "docker", "options": []},
            ]
            _paths = os.environ["PATH"].split(":")
            for p in _paths:
                for _installer in installers:
                    _fp = p + "/" + str(_installer["bin"])
                    if os.path.isfile(_fp):
                        global messages
                        messages = messages + [
                            "Found system installer binary " + str(_installer["bin"])
                        ]
                        return _installer

    def copy_config(self, _file=None, _dirs=None):
        if _file is None:
            _file = self.nginx_conf
        if _dirs is None:
            _dirs = self.site_dirs

        outfile = "/%s" % _file.__str__()
        if os.path.isdir(_dirs[0]):
            os.system("sudo cp %s %s" % (_file, _dirs[0] + outfile))
        else:
            os.system("sudo mkdir %s" % _dirs[0])
            os.system("sudo cp %s %s" % (_file, _dirs[0] + outfile))
        try:
            if os.path.isdir(_dirs[1]):
                ln_string = str(_dirs[0] + outfile + " " + _dirs[1] + outfile)
                os.system("sudo ln -s %s" % ln_string)
        except Exception as e:
            pass
        return True

    def make_nginx_config(self, answers):
        root = os.path.abspath(".")
        _fp = "pyshelf_nginx.conf"
        for r in answers:
            if r["name"] == "hostname":
                hostname = r["answer"]
            elif r["name"] == "webport":
                port = r["answer"]
            elif r["name"] == "wsgiport":
                wsgiport = r["answer"]
        nginx_conf_str = """
        # pyshelf_nginx.conf
        upstream django {server unix://%s/pyshelf_wsgi.sock;}
        server {
            listen      %s;
            server_name %s;
            access_log  /var/log/nginx/pyshelf.access.log;
            error_log  /var/log/nginx/pyshelf.error.log;
            charset     utf-8;
            client_max_body_size 75M;
            location /media  {root %s/src/interface;}
            location /static {root %s/src/interface;}
            location /books {internal; alias %s;}
            location / {uwsgi_pass django; include %s/uwsgi_params;}
        }
        """ % (
            root,
            port,
            hostname,
            root,
            root,
            root,
            root,
        )
        with open(_fp, "w") as write_file:
            write_file.write(nginx_conf_str)
        global messages
        messages = messages + ["Generated new pyshelf_nginx.conf", nginx_conf_str]

    def make_wsgi_config(self, answers):
        root = os.path.abspath(".")
        _fp = "uwsgi.ini"
        for r in answers:
            if r["name"] == "hostname":
                hostname = r["answer"]
            elif r["name"] == "wsgiport":
                wsgiport = r["answer"]
        wsgi_conf_str = """
        [uwsgi]
        chdir=%s/src
        module=frontend.wsgi
        master=True
        pidfile=/tmp/pyShelf.pid
        vacuum=True
        socket=%s/pyshelf_wsgi.sock
        chmod-socket=666
        """ % (
            root,
            root
        )
        with open(_fp, "w") as write_file:
            write_file.write(wsgi_conf_str)
        global messages
        messages = messages + ["Generated uwsgi.ini", wsgi_conf_str]

    def log(self):
        global log_file
        global messages
        with open(log_file, "w") as write_file:
            write_file.write(TerminalDisplay().banner_render())
            for message in messages:
                write_file.write(message + "\n")
        messages = messages + ["Log file written to " + log_file.__str__()]


config = Configuration().open_file()
sysinstall = SystemInstaller()
installer = sysinstall.bin
# Get user configuration options
install_answers = TerminalDisplay().installer()
for key in install_answers:
    config[key["name"]] = key["answer"]
config["USER"] = os.environ["USER"]
# Write configuration
Configuration().write_file(config)

# Start checking for our list of required services
service_list = ["postgres", "nginx", "httpd", "test"]
req = RequiredServices().check_ps(service_list)

# Does user have either nginx || apache?
if RequiredServices().web_server_found(req) is False:
    web_prompt = [
        {
            "message": " You must have either apache or nginx\n would you like us to try and install nginx now?  > ",
            "options": "nginx",
            "name": "NGINX",
            "answer": None,
            "default": "no",
        }
    ]
    install_prompt = TerminalDisplay().prompt(web_prompt)
    if install_prompt[0]["answer"] == "yes":
        if installer is None:
            installer = SystemInstaller().bin
        if installer["bin"] == "pacman":
            package = "nginx-mainline"
        else:
            package = "nginx"
        options = ""
        for o in installer["options"]:
            options = options + " " + o
        cmd = (
            "sudo "
            + installer["bin"]
            + " "
            + installer["install"]
            + " "
            + options
            + package
        )
        install_status = os.system(cmd)
        os.system("sudo systemctl start nginx")
        messages = messages + [
            "Nginx installed and started",
            "To enable autostart you must run",
            "    sudo systemctl enable nginx",
            "\n",
        ]
# Does user have postgreSQL?
if RequiredServices().db_server_found(req) is False:
    db_prompt = [
        {
            "message": " You must have PostgreSQL\n would you like us to try and install it now? > ",
            "options": "postgres",
            "name": "postgresql",
            "answer": None,
            "default": "no",
        }
    ]
    install_prompt = TerminalDisplay().prompt(db_prompt)
    if install_prompt[0]["answer"] == "yes":
        if installer is None:
            installer = SystemInstaller().bin
        options = ""
        for o in installer["options"]:
            options = options + " " + o
        package = "postgresql postgresql-contrib"
        cmd = (
            "sudo "
            + installer["bin"]
            + " "
            + installer["install"]
            + " "
            + options
            + package
        )
        install_status = os.system(cmd)
        for r in install_answers:
            if r["name"] == "PASSWORD": sql_pass = r["answer"]

        sql_user = config["USER"]
        db_name = "pyshelf"
        psql_cmd = """
        CREATE DATABASE %s;
        CREATE USER %s WITH PASSWORD \'%s\';
        GRANT ALL PRIVILEGES ON DATABASE %s TO %s;
        """ % (db_name, sql_user, sql_pass, db_name, sql_user)
        _sql_file = "create_db.sql"
        with open(_sql_file, "w") as sql_file_open:
            sql_file_open.write(psql_cmd)
        sql_file_open.close()
        os.system("sudo systemctl start postgresql")
        os.system("sudo -u postgres initdb --locale=en_US.UTF-8 -E UTF8 -D /var/lib/postgres/data")
        os.system("sudo -u postgres psql -f %s"%_sql_file)
        messages = messages + [
            "PostgreSQL installed and started",
            "To enable autostart you must run",
            "    sudo systemctl enable nginx",
            "\n",
            "Database cluster initialized at /var/lib/postgres",
            "pyShelf database and user created",
            psql_cmd
        ]

# Post install configurations
sysinstall.make_nginx_config(install_answers)
try:
    os.chdir("src/")
    os.system("python manage.py makemigrations")
    os.system("python manage.py makemigrations interface")
    os.system("python manage.py migrate")
    os.system("python manage.py migrate interface")
    os.chdir("../")
except Exception as e:
    print("-"*80)
    print(" E:"+e)
try:
    copy_config = sysinstall.copy_config()
    if copy_config:
        messages = messages + ["pyShelf site config copied to sites-available, and symlinked to sites-enabled"]
except Exception as e:
    messages = messages + ["nginx site config not copied", "A nginx config for your install has been created \"pyshelf_nginx.conf\""]
sysinstall.make_wsgi_config(install_answers)
messages = messages + ["You should now import your books by running importBooks", "You can then start the interface with uwsgi --ini uwsgi.ini"]

# Display end screen
sysinstall.log()
TerminalDisplay().clear()
TerminalDisplay().banner()
for message in messages:
    print(" "+message)
print()

TerminalDisplay().h_rule()