-
Notifications
You must be signed in to change notification settings - Fork 0
/
Adoption.sol
77 lines (61 loc) · 2.08 KB
/
Adoption.sol
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
pragma solidity 0.4.23;
contract Adoption {
event NameAssigned(uint256 indexed petId, bytes32 name);
event Adopted(uint256 indexed petId, address indexed adopter);
struct Pet {
address adopter;
bool exists;
}
mapping (uint256 => Pet) private pets;
address public contractOwnerAddress = msg.sender;
modifier messageSenderIsContractOwner() {
require(msg.sender == contractOwnerAddress);
_;
}
modifier messageSenderIsAdopter(uint256 petId) {
require(pets[petId].exists);
require(pets[petId].adopter == msg.sender);
_;
}
modifier petExists(uint256 petId) {
require(pets[petId].exists);
_;
}
modifier petDoesNotExist(uint256 petId) {
require(!(pets[petId].exists));
_;
}
modifier petIsNotAdopted(uint256 petId) {
require(pets[petId].exists);
require(pets[petId].adopter == address(0));
_;
}
modifier addressIsAdopter(address claimant, uint256 petId) {
require(pets[petId].exists);
require(pets[petId].adopter == claimant);
_;
}
function transfer(uint256 petId, address to) public messageSenderIsAdopter(petId) petExists(petId) {
pets[petId].adopter = to;
}
function createAdoptee(uint256 petId) public messageSenderIsContractOwner {
Pet memory pet = Pet({
adopter: address(0),
exists: true
});
pets[petId] = pet;
}
function adopterOf(uint256 petId) public view petExists(petId) returns (address adopter) {
adopter = pets[petId].adopter;
}
function adopt(uint256 petId) public petIsNotAdopted(petId) petExists(petId) {
pets[petId].adopter = msg.sender;
emit Adopted(petId, msg.sender);
}
function isAdopted(uint256 petId) public view petExists(petId) returns (bool adopted) {
adopted = pets[petId].adopter != address(0);
}
function assignName(uint256 petId, bytes32 name) external messageSenderIsAdopter(petId) petExists(petId) {
emit NameAssigned(petId, name);
}
}