1/*
  2    Copyright 2018 0kims association.
  3
  4    This file is part of zksnark JavaScript library.
  5
  6    zksnark JavaScript library is a free software: you can redistribute it and/or 
  7    modify it under the terms of the GNU General Public License as published by the 
  8    Free Software Foundation, either version 3 of the License, or (at your option) 
  9    any later version.
 10
 11    zksnark JavaScript library is distributed in the hope that it will be useful,
 12    but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 13    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 
 14    more details.
 15
 16    You should have received a copy of the GNU General Public License along with 
 17    zksnark JavaScript library. If not, see <https://www.gnu.org/licenses/>.
 18*/
 19
 20const bigInt = require("./bigint.js");
 21
 22const __P__ = bigInt("21888242871839275222246405745257275088548364400416034343698204186575808495617");
 23const __MASK__ = bigInt("28948022309329048855892746252171976963317496166410141009864396001978282409983"); // 0x3FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 24const calculateWitness = require("./calculateWitness.js");
 25
 26module.exports = class Circuit {
 27    constructor(circuitDef) {
 28        this.nPubInputs = circuitDef.nPubInputs;
 29        this.nPrvInputs = circuitDef.nPrvInputs;
 30        this.nInputs = circuitDef.nInputs;
 31        this.nOutputs = circuitDef.nOutputs;
 32        this.nVars = circuitDef.nVars;
 33        this.nSignals = circuitDef.nSignals;
 34        this.nConstants = circuitDef.nConstants;
 35
 36        this.nConstraints = circuitDef.constraints.length;
 37
 38        this.signalName2Idx = circuitDef.signalName2Idx;
 39        this.components = circuitDef.components;
 40        this.componentName2Idx = circuitDef.componentName2Idx;
 41        this.signals = circuitDef.signals;
 42        this.constraints = circuitDef.constraints;
 43
 44        this.templates = {};
 45        for (let t in circuitDef.templates) {
 46            this.templates[t] = eval(" const __f= " +circuitDef.templates[t] + "\n__f");
 47        }
 48
 49        this.functions = {};
 50        for (let f in circuitDef.functions) {
 51            this.functions[f] = {
 52                params: circuitDef.functions[f].params,
 53                func: eval(" const __f= " +circuitDef.functions[f].func + "\n__f;")
 54            };
 55        }
 56    }
 57
 58    calculateWitness(input) {
 59        return calculateWitness(this, input);
 60    }
 61
 62    getSignalIdx(name) {
 63        if (typeof(this.signalName2Idx[name]) != "undefined") return this.signalName2Idx[name];
 64        if (!isNaN(name)) return Number(name);
 65        throw new Error("Invalid signal identifier: ", name);
 66    }
 67
 68    // returns the index of the i'th output
 69    outputIdx(i) {
 70        if (i>=this.nOutputs) throw new Error("Accessing an invalid output: "+i);
 71        return i+1;
 72    }
 73
 74    // returns the index of the i'th input
 75    inputIdx(i) {
 76        if (i>=this.nInputs) throw new Error("Accessing an invalid input: "+i);
 77        return this.nOutputs + 1 + i;
 78    }
 79
 80    // returns the index of the i'th public input
 81    pubInputIdx(i) {
 82        if (i>=this.nPubInputs) throw new Error("Accessing an invalid pubInput: "+i);
 83        return this.inputIdx(i);
 84    }
 85
 86    // returns the index of the i'th private input
 87    prvInputIdx(i) {
 88        if (i>=this.nPrvInputs) throw new Error("Accessing an invalid prvInput: "+i);
 89        return this.inputIdx(this.nPubInputs + i);
 90    }
 91
 92    // returns the index of the i'th variable
 93    varIdx(i) {
 94        if (i>=this.nVars) throw new Error("Accessing an invalid variable: "+i);
 95        return i;
 96    }
 97
 98    // returns the index of the i'th constant
 99    constantIdx(i) {
100        if (i>=this.nConstants) throw new Error("Accessing an invalid constant: "+i);
101        return this.nVars + i;
102    }
103
104    // returns the index of the i'th signal
105    signalIdx(i) {
106        if (i>=this.nSignls) throw new Error("Accessing an invalid signal: "+i);
107        return i;
108    }
109
110    signalNames(i) {
111        return this.signals[ this.getSignalIdx(i) ].names.join(", ");
112    }
113
114    a(constraint, signalIdx) {
115        return bigInt(this.constraints[constraint][0][signalIdx] || 0 );
116    }
117
118    b(constraint, signalIdx) {
119        return bigInt(this.constraints[constraint][1][signalIdx] || 0);
120    }
121
122    c(constraint, signalIdx) {
123        return bigInt(this.constraints[constraint][2][signalIdx] || 0);
124    }
125};