"""
This example prints all database hierarchy
"""

import sys
from ttdb.model import HierarchyElement, Crate, obtain_session


def print_hierarchy(element, level):
    assert isinstance(element, HierarchyElement)

    #spases to highlight hierarchy level
    spaces = " "*6*int(level)

    #if element has children id build semi graphical line to it
    if element.channel_id:
        # crate name
        relation_str = "  --->  '{}' -> ".format(element.channel.module.crate.name)

        #module info
        module = element.channel.module
        relation_str += "'module(db={}) SN({}) at slot('{}')' -> ".format(module.id, module.serial, module.slot)

        #channel info
        channel = element.channel
        relation_str += "'channel={} enabled={}'".format(channel.channel, channel.enabled)
    else:
        relation_str = ""

    #print info
    print ("{} {} ({}) {}".format(spaces, element.name, element.type, relation_str))

    #recursively iterate through children
    if len(element.children):
        for child in element.children:
            print_hierarchy(child, level+1)


if __name__ == "__main__":

    #get connection string
    if len(sys.argv) <= 1:
        exit("Provide connection string for database. For sqlite use 'sqlite:///<path>' (Note 3 slashes)")

    session = obtain_session(sys.argv[1])

    #select all root level elements
    elements = session.query(HierarchyElement).filter(HierarchyElement.parent_id == None).all()

    #iterate it
    for element in elements:
        print_hierarchy(element, 0)

    #print crate->Module info
    print("--------------------------------------------------")
    print("            C R A T E       M O D U L E           ")
    print("--------------------------------------------------")

    #select first (by id) crate
    crate = session.query(Crate).order_by(Crate.id).first()
    print("{}".format(crate.name))
    for module in crate.modules:
        print("       {} ==> {}   (id={})".format(module.slot, module.type, module.id))