path: root/geldschieberbot.py

#!/usr/bin/env python3

import json
import os
import subprocess
import sys

import tanken

"""Dict of dicts associating a second person to an amount"""
balance = {}

name2num = {}
num2name = {}

group_id = "GELD!!!"

send_cmd = "signal-cli -u irgendwer send -g irgendwem"

def to_cent(euro):
    euro = euro.split('.')
    if len(euro) > 2:
        raise TypeError
    euro[0] = int(euro[0])
    if len(euro) < 2:
        euro.append(0)
    else:
        if len(euro[1]) == 1:
            euro[1] = int(euro[1]) * 10
        else:
            euro[1] = int(euro[1])
    return euro[0] * 100 + euro[1]

def to_euro(cents):
    return str(cents/100)

def send(msg):
    subprocess.run(send_cmd.split(' '), input=msg.encode())

def create_summary(user):
    summary = ""
    total = 0
    p_balances = balance[user] # failes if user is not in balance
    for person in p_balances:
        amount = p_balances[person]
        if amount == 0:
            continue
        total -= amount
        summary += "\t{} {} {}\n".format("<-" if amount < 0 else "->", person, to_euro(abs(amount)))
    if summary == "":
        summary = "\tAll fine :)\n"
    else:
        summary += "\tBalance: {}".format(to_euro(total))
    summary = user + ":\n" + summary
    return summary

def create_total_summary():
    summary = "Summary:"

    for person in balance:
        summary += '\n'
        summary += "* " + create_summary(person)

    return summary

def create_members():
    r = ""
    for m in name2num:
        r += m + ": " + name2num[m] + "\n"
    return r

def create_help():
    return """
Usage: send a message starting with '!' followed by a command
Commands:
ls | list                - print all registered members
help                     - print this help message
reg name                 - register the sender with the name: name
sum [name]               - print a summary
schieb amount recipient  - give money to recipient
zieh amount donor        - get money from donor
	
Happy Geldschieben!
"""

def handle_input(inp):
    messages = inp.split("\n\n")
    for message in messages:
        lines = message.split('\n')

        # A message with Body must have at least 4 lines
        if len(lines) < 4:
            continue

        lines[0].lower()
        w = lines[0].split(' ')

        # Broken message
        if len(w) < 4:
            print("Broken msg:")
            print(message)
            continue

        # TODO support linked devices
        sender_number = w[-3]

        body_found = False
        body = []

        # message is not in the group with group_id 
        not_in_group = True

        for idx, line in enumerate(lines[1:]):
            # Collect body till we find Group ID:
            # THIS COULD BREAK VERY EASILY
            if line[0:6] == "Body: ":
                body.append(line[6:])
                body_found = True
            elif body_found:
                if not line == "Group info:":
                    body.append(line)
                else:
                    not_in_group = lines[idx+1].strip() == "Id: " + group_id
                    break

        if not_in_group:
            continue

        w = body[0].lower().split(' ')

        cmd = w[0]

        # supported commands are:
        # "!reg"           register a name for this number
        # "!sum"           send a summary to the group
        # "!schieb" "!gib" give money to somebody
        # "!zieh" "!nimm"  add debt of somebody
        # "!list" "!ls"    list members
        # "!tanken"        calculate fuel cost parts
        # "!help"          print all commands
        if cmd == "!reg":
            if len(w) != 2:
                send('ERROR: not in form "!reg name"')
            else:
                if w[1] in name2num:
                    send("ERROR: name already registered")
                elif sender_number in num2name:
                    send("ERROR: you are already registered")
                else:
                    num2name[sender_number] = w[1]
                    name2num[w[1]] = sender_number

                    # add to balance
                    nm = {}
                    for m in balance:
                        balance[m][w[1]] = 0
                        nm[m] = 0
                    balance[w[1]] = nm

        elif cmd == "!sum":
            if len(w) == 1:
                send(create_total_summary())
            elif len(w) == 2:
                if w[1] in name2num:
                    send("Summary:\n" + create_summary(w[1]))
                else:
                    send("ERROR: name not registered")
            else:
                send('ERROR: not in form "!sum [name]"')

        elif cmd == "!list" or cmd == "!ls":
            send(create_members())

        elif cmd == "!help":
            send(create_help())

        elif cmd in ["!schieb", "!gib", "!zieh", "!nimm"]:
            if len(w) != 3:
                send('ERROR: not in form "!cmd amount recipient"')
            else:
                if not sender_number in num2name:
                    send('ERROR: you must register first')
                else:
                    if w[1] in name2num:
                        recipient = w[1]
                        amount = w[2]
                    elif w[2] in name2num:
                        recipient = w[2]
                        amount = w[1]
                    else:
                        send('ERROR: recipient not known')
                        continue

                    sender = num2name[sender_number]

                    try:
                        amount = to_cent(amount)
                    except:
                        send("ERROR: amount musst be a number")
                        continue

                    if amount < 0:
                        send("ERROR: amount must be positiv")
                        continue

                    if cmd in ["!zieh", "!nimm"]:
                        amount *= -1

                    balance[sender][recipient] -= amount
                    balance[recipient][sender] += amount

                    p_balance = balance[sender][recipient]

                    send("New Balance: {} {} {} {}\n".format(sender,
                                                                ("->" if p_balance > 0 else "<-"),
                                                                to_euro(abs(p_balance)),
                                                                recipient))
                
        elif cmd == "!tanken":
            if len(w) < 3:
                send('ERROR: !tanken not in form "!tanken amount person [info]"')
                continue
            try:
                amount = to_cent(w[1])
            except:
                send("ERROR: amount musst be a number")
                continue

            if w[2] in name2num:
                recipient = w[2]
            else:
                recipient = num2name[sender_number]

            parts, err = tanken.tanken(body[1:], amount)

            if err != None:
                send("ERROR: " + err)
                continue

            msg = ""
            for p in parts.items():
                msg += p[0] + ": {}km = {}\n".format(p[1][0], to_euro(p[1][1]))
                if p[0] != recipient:
                    if p[0] in name2num:
                        balance[recipient][p[0]] -= p[1][1]
                        balance[p[0]][recipient] += p[1][1]
                    else:
                        msg += p[0] + " not known. Please take care manually\n"

            msg += "New Balance:\n"
            msg += create_summary(recipient)
            send(msg)


def main():
    global group_id
    group_id = os.environ["GSB_GROUP_ID"]

    global balance
    store_path = os.environ["GSB_STORE_PATH"]
    balance_path = store_path + "/balance.json"
    registration_path = store_path + "/registration.json"

    global name2num
    global num2name

    global send_cmd
    send_cmd = os.environ["GSB_SEND_CMD"]

    if os.path.isfile(balance_path):
            balance = json.load(open(balance_path, "r"))

    if os.path.isfile(registration_path):
            name2num = json.load(open(registration_path, "r"))
            for name in name2num:
                num2name[name2num[name]] = name

    handle_input(sys.stdin.read())

    with open(balance_path, "w") as f:
        json.dump(balance, f)

    with open(registration_path, "w") as f:
        json.dump(name2num, f)

if __name__ == "__main__":
    main()