""" Warehouse API """

import os
from dataclasses import dataclass

#
# Dataclasses
#
@dataclass
class WarehouseLocation:
    """ Location inside warehouse """
    # human readable name of location within warehouse
    name: str
    # description on how to find the location
    how_to_find: str = 'Somewhere inside the warehouse'
    # remarks
    remarks: str = ''

@dataclass
class WarehouseItem:
    """ Item stored within warehouse """
    # human readable name of item
    name: str
    # human readable name of measurement unit
    unit: str = 'units'
    # count of item in units
    count: int = 1
    # remarks
    remarks: str = ''
    # location ID where the item is stored
    location_id: int = 0

#
# Private
#
_warehouse_name = None
_warehouse_path = None
_locations = {}
_entries = {}

async def _read_file(path: str) -> str:
    """ Read file content and strip it.
        Empty string on error.
    """
    try:
        with open(path, 'r') as f:
            return f.read().strip()
    except:
        return ''

async def _write_file(path: str, content: str) -> bool:
    """ Write file content. """
    try:
        with open(path, 'w') as f:
            f.write(content)
        return True
    except:
        return False

async def _fsck_warehouse(path: str) -> bool:
    """ Check warehouse for errors and fix them if possible.
        Returns True if warehouse is usable.
    """
    if not os.path.isdir(path):
        return False

async def _create_warehouse(path: str) -> bool:
    """ Create warehouse.
        Returns True if warehouse is usable.
    """
    if os.path.isdir(path):
        return await _fsck_warehouse(path)
    locations[0] = WarehouseLocation(
        name='Unsorted',
        how_to_find='',
        remarks='Pseudolocation for unsorted items'
    )
    
    

#
# Public
#
async def init(name: str) -> bool:
    """ Initialize warehouse API. """
    global _warehouse_name, _warehouse_path
    _warehouse_name = name
    _warehouse_path = f'warehouse_{name}'
    return await _create_warehouse(_warehouse_path)