#! /usr/bin/env python3
import os
import sys
import yaml
import re
from xdg import XDG_CONFIG_HOME, XDG_DATA_HOME
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
import models
import locale

try:
    from yaml import CLoader as Loader
except ImportError:
    from yaml import Loader


CONFIG_DIR = os.path.join(XDG_CONFIG_HOME, "schmeckels")
DATA_DIR = os.path.join(XDG_DATA_HOME, "schmeckels")


def format_amount(cents):
    amount = cents/100
    return f"{amount:,.2f}"


def get_list_of_bookable_categories(session):
    categories = session.query(models.Category).all()
    return [c for c in categories if c.is_child()]


def create_dirs():
    for directory in [CONFIG_DIR, DATA_DIR]:
        try:
            os.mkdir(directory)
        except FileExistsError:
            pass


def build_database_filename(profile_name):
    return f"{DATA_DIR}/databases/{profile_name}.db"


def build_rules_filename(profile_name):
    return f"{DATA_DIR}/rules/{profile_name}.yaml"


def check_single_profile():
    files = os.listdir(f"{DATA_DIR}/databases")
    if len(files) == 1:
        return files.split(".")[0]
    else:
        print("--profile is required when you have more than one database.")
        sys.exit(1)


def list_profiles():
    files = os.listdir(f"{DATA_DIR}/databases")
    return [x.split(".")[0] for x in files]


def get_session(profile_name):
    if not profile_name:
        profile_name = check_single_profile()
    filename = build_database_filename(profile_name)
    if os.path.exists(filename) and os.path.isfile(filename):
        engine = create_engine(f"sqlite:///{filename}")
        Session = sessionmaker(bind=engine)
        return Session()
    else:
        print(f"No database for profile '{profile_name}'. Did you run 'init'?")
        sys.exit(1)


def get_rules(profile_name):
    if not profile_name:
        profile_name = check_single_profile()
    filename = build_rules_filename(profile_name)
    if os.path.exists(filename) and os.path.isfile(filename):
        with open(filename) as fh:
            data = yaml.load(fh, Loader=Loader)
        for rule in data:
            if rule.get("name"):
                rule["name_regex"] = re.compile(rule["name"])
            if rule.get("description"):
                rule["desc_regex"] = re.compile(rule["description"])
        return data
    else:
        print(f"No rules for profile '{profile_name}'. Did you run 'init'?")
        sys.exit(1)


def create_category(name, parent, profile, session):
    c = session.query(models.Category).filter(models.Category.name == name).first()
    if not c:
        c = models.Category(name=name, parent_id=parent)
        session.add(c)
        session.commit()
    return c.id


def add_category(name, profile, session):
    parts = name.split(":")
    if len(parts) == 1:
        return create_category(name, None, profile, session)
    else:
        for i in range(len(parts) - 1):
            parent = parts[i]
            child = parts[i + 1]
            parent_id = create_category(parent, None, profile, session)
            id = create_category(child, parent_id, profile, session)
        return id