# A tip jar: anyone can send TCN with a message, only the owner withdraws.
contract TipJar

state owner: address
state total_received: int
state tips: int

event Tip(from: address, amount: int, message: text)
event Withdrawn(to: address, amount: int)

init():
    owner = caller

action tip(message: text) payable:
    require value >= TCN / 100, "minimum tip is 0.01 TCN"
    require len(message) <= 140, "message too long"
    total_received += value
    tips += 1
    emit Tip(caller, value, message)

action withdraw(amount: int):
    require caller == owner, "only the owner can withdraw"
    require amount > 0 and amount <= balance, "invalid amount"
    send(owner, amount)
    emit Withdrawn(owner, amount)

view stats() -> list[int]:
    return [total_received, tips, balance]