/*
This file is part of ethereum.js.
ethereum.js is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ethereum.js is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with ethereum.js. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file contract.js
* @authors:
* Marek Kotewicz <marek@ethdev.com>
* @date 2014
*/
var web3 = require('./web3');
var abi = require('./abi');
var utils = require('./utils');
var eventImpl = require('./event');
var exportNatspecGlobals = function (vars) {
// it's used byt natspec.js
// TODO: figure out better way to solve this
web3._currentContractAbi = vars.abi;
web3._currentContractAddress = vars.address;
web3._currentContractMethodName = vars.method;
web3._currentContractMethodParams = vars.params;
};
var addFunctionRelatedPropertiesToContract = function (contract) {
contract.call = function (options) {
contract._isTransact = false;
contract._options = options;
return contract;
};
contract.transact = function (options) {
contract._isTransact = true;
contract._options = options;
return contract;
};
contract._options = {};
['gas', 'gasPrice', 'value', 'from'].forEach(function(p) {
contract[p] = function (v) {
contract._options[p] = v;
return contract;
};
});
};
var addFunctionsToContract = function (contract, desc, address) {
var inputParser = abi.inputParser(desc);
var outputParser = abi.outputParser(desc);
// create contract functions
utils.filterFunctions(desc).forEach(function (method) {
var displayName = utils.extractDisplayName(method.name);
var typeName = utils.extractTypeName(method.name);
var impl = function () {
var params = Array.prototype.slice.call(arguments);
var signature = abi.signatureFromAscii(method.name);
var parsed = inputParser[displayName][typeName].apply(null, params);
var options = contract._options || {};
options.to = address;
options.data = signature + parsed;
var isTransact = contract._isTransact === true || (contract._isTransact !== false && !method.constant);
var collapse = options.collapse !== false;
// reset
contract._options = {};
contract._isTransact = null;
if (isTransact) {
exportNatspecGlobals({
abi: desc,
address: address,
method: method.name,
params: params
});
// transactions do not have any output, cause we do not know, when they will be processed
web3.eth.transact(options);
return;
}
var output = web3.eth.call(options);
var ret = outputParser[displayName][typeName](output);
if (collapse)
{
if (ret.length === 1)
ret = ret[0];
else if (ret.length === 0)
ret = null;
}
return ret;
};
if (contract[displayName] === undefined) {
contract[displayName] = impl;
}
contract[displayName][typeName] = impl;
});
};
var addEventRelatedPropertiesToContract = function (contract, desc, address) {
contract.address = address;
contract._onWatchEventResult = function (data) {
var matchingEvent = event.getMatchingEvent(utils.filterEvents(desc));
var parser = eventImpl.outputParser(matchingEvent);
return parser(data);
};
Object.defineProperty(contract, 'topic', {
get: function() {
return utils.filterEvents(desc).map(function (e) {
return abi.eventSignatureFromAscii(e.name);
});
}
});
};
var addEventsToContract = function (contract, desc, address) {
// create contract events
utils.filterEvents(desc).forEach(function (e) {
var impl = function () {
var params = Array.prototype.slice.call(arguments);
var signature = abi.eventSignatureFromAscii(e.name);
var event = eventImpl.inputParser(address, signature, e);
var o = event.apply(null, params);
o._onWatchEventResult = function (data) {
var parser = eventImpl.outputParser(e);
return parser(data);
};
return web3.eth.watch(o);
};
// this property should be used by eth.filter to check if object is an event
impl._isEvent = true;
var displayName = utils.extractDisplayName(e.name);
var typeName = utils.extractTypeName(e.name);
if (contract[displayName] === undefined) {
contract[displayName] = impl;
}
contract[displayName][typeName] = impl;
});
};
/**
* This method should be called when we want to call / transact some solidity method from javascript
* it returns an object which has same methods available as solidity contract description
* usage example:
*
* var abi = [{
* name: 'myMethod',
* inputs: [{ name: 'a', type: 'string' }],
* outputs: [{name: 'd', type: 'string' }]
* }]; // contract abi
*
* var myContract = web3.eth.contract('0x0123123121', abi); // creation of contract object
*
* myContract.myMethod('this is test string param for call'); // myMethod call (implicit, default)
* myContract.call().myMethod('this is test string param for call'); // myMethod call (explicit)
* myContract.transact().myMethod('this is test string param for transact'); // myMethod transact
*
* @param address - address of the contract, which should be called
* @param desc - abi json description of the contract, which is being created
* @returns contract object
*/
var contract = function (address, desc) {
// workaround for invalid assumption that method.name is the full anonymous prototype of the method.
// it's not. it's just the name. the rest of the code assumes it's actually the anonymous
// prototype, so we make it so as a workaround.
// TODO: we may not want to modify input params, maybe use copy instead?
desc.forEach(function (method) {
if (method.name.indexOf('(') === -1) {
var displayName = method.name;
var typeName = method.inputs.map(function(i){return i.type; }).join();
method.name = displayName + '(' + typeName + ')';
}
});
var result = {};
addFunctionRelatedPropertiesToContract(result);
addFunctionsToContract(result, desc, address);
addEventRelatedPropertiesToContract(result, desc, address);
addEventsToContract(result, desc, address);
return result;
};
module.exports = contract;
