const { constants, expectEvent, expectRevert } = require('@openzeppelin/test-helpers');
const { expect } = require('chai');

const ERC721ConsecutiveMock = artifacts.require('$ERC721ConsecutiveMock');
const ERC721ConsecutiveEnumerableMock = artifacts.require('$ERC721ConsecutiveEnumerableMock');
const ERC721ConsecutiveNoConstructorMintMock = artifacts.require('$ERC721ConsecutiveNoConstructorMintMock');

contract('ERC721Consecutive', function (accounts) {
  const [user1, user2, user3, receiver] = accounts;

  const name = 'Non Fungible Token';
  const symbol = 'NFT';
  const batches = [
    { receiver: user1, amount: 0 },
    { receiver: user1, amount: 3 },
    { receiver: user2, amount: 5 },
    { receiver: user3, amount: 0 },
    { receiver: user1, amount: 7 },
  ];
  const delegates = [user1, user3];

  describe('with valid batches', function () {
    beforeEach(async function () {
      this.token = await ERC721ConsecutiveMock.new(
        name,
        symbol,
        delegates,
        batches.map(({ receiver }) => receiver),
        batches.map(({ amount }) => amount),
      );
    });

    describe('minting during construction', function () {
      it('events are emitted at construction', async function () {
        let first = 0;

        for (const batch of batches) {
          if (batch.amount > 0) {
            await expectEvent.inConstruction(this.token, 'ConsecutiveTransfer', {
              fromTokenId: web3.utils.toBN(first),
              toTokenId: web3.utils.toBN(first + batch.amount - 1),
              fromAddress: constants.ZERO_ADDRESS,
              toAddress: batch.receiver,
            });
          } else {
            // expectEvent.notEmitted.inConstruction only looks at event name, and doesn't check the parameters
          }
          first += batch.amount;
        }
      });

      it('ownership is set', async function () {
        const owners = batches.flatMap(({ receiver, amount }) => Array(amount).fill(receiver));

        for (const tokenId in owners) {
          expect(await this.token.ownerOf(tokenId)).to.be.equal(owners[tokenId]);
        }
      });

      it('balance & voting power are set', async function () {
        for (const account of accounts) {
          const balance = batches
            .filter(({ receiver }) => receiver === account)
            .map(({ amount }) => amount)
            .reduce((a, b) => a + b, 0);

          expect(await this.token.balanceOf(account)).to.be.bignumber.equal(web3.utils.toBN(balance));

          // If not delegated at construction, check before + do delegation
          if (!delegates.includes(account)) {
            expect(await this.token.getVotes(account)).to.be.bignumber.equal(web3.utils.toBN(0));

            await this.token.delegate(account, { from: account });
          }

          // At this point all accounts should have delegated
          expect(await this.token.getVotes(account)).to.be.bignumber.equal(web3.utils.toBN(balance));
        }
      });
    });

    describe('minting after construction', function () {
      it('consecutive minting is not possible after construction', async function () {
        await expectRevert(
          this.token.$_mintConsecutive(user1, 10),
          'ERC721Consecutive: batch minting restricted to constructor',
        );
      });

      it('simple minting is possible after construction', async function () {
        const tokenId = batches.reduce((acc, { amount }) => acc + amount, 0);

        expect(await this.token.$_exists(tokenId)).to.be.equal(false);

        expectEvent(await this.token.$_mint(user1, tokenId), 'Transfer', {
          from: constants.ZERO_ADDRESS,
          to: user1,
          tokenId: tokenId.toString(),
        });
      });

      it('cannot mint a token that has been batched minted', async function () {
        const tokenId = batches.reduce((acc, { amount }) => acc + amount, 0) - 1;

        expect(await this.token.$_exists(tokenId)).to.be.equal(true);

        await expectRevert(this.token.$_mint(user1, tokenId), 'ERC721: token already minted');
      });
    });

    describe('ERC721 behavior', function () {
      it('core takes over ownership on transfer', async function () {
        await this.token.transferFrom(user1, receiver, 1, { from: user1 });

        expect(await this.token.ownerOf(1)).to.be.equal(receiver);
      });

      it('tokens can be burned and re-minted #1', async function () {
        expectEvent(await this.token.$_burn(1, { from: user1 }), 'Transfer', {
          from: user1,
          to: constants.ZERO_ADDRESS,
          tokenId: '1',
        });

        await expectRevert(this.token.ownerOf(1), 'ERC721: invalid token ID');

        expectEvent(await this.token.$_mint(user2, 1), 'Transfer', {
          from: constants.ZERO_ADDRESS,
          to: user2,
          tokenId: '1',
        });

        expect(await this.token.ownerOf(1)).to.be.equal(user2);
      });

      it('tokens can be burned and re-minted #2', async function () {
        const tokenId = batches.reduce((acc, { amount }) => acc.addn(amount), web3.utils.toBN(0));

        expect(await this.token.$_exists(tokenId)).to.be.equal(false);
        await expectRevert(this.token.ownerOf(tokenId), 'ERC721: invalid token ID');

        // mint
        await this.token.$_mint(user1, tokenId);

        expect(await this.token.$_exists(tokenId)).to.be.equal(true);
        expect(await this.token.ownerOf(tokenId), user1);

        // burn
        expectEvent(await this.token.$_burn(tokenId, { from: user1 }), 'Transfer', {
          from: user1,
          to: constants.ZERO_ADDRESS,
          tokenId,
        });

        expect(await this.token.$_exists(tokenId)).to.be.equal(false);
        await expectRevert(this.token.ownerOf(tokenId), 'ERC721: invalid token ID');

        // re-mint
        expectEvent(await this.token.$_mint(user2, tokenId), 'Transfer', {
          from: constants.ZERO_ADDRESS,
          to: user2,
          tokenId,
        });

        expect(await this.token.$_exists(tokenId)).to.be.equal(true);
        expect(await this.token.ownerOf(tokenId), user2);
      });
    });
  });

  describe('invalid use', function () {
    it('cannot mint a batch larger than 5000', async function () {
      await expectRevert(
        ERC721ConsecutiveMock.new(name, symbol, [], [user1], ['5001']),
        'ERC721Consecutive: batch too large',
      );
    });

    it('cannot use single minting during construction', async function () {
      await expectRevert(
        ERC721ConsecutiveNoConstructorMintMock.new(name, symbol),
        "ERC721Consecutive: can't mint during construction",
      );
    });

    it('cannot use single minting during construction', async function () {
      await expectRevert(
        ERC721ConsecutiveNoConstructorMintMock.new(name, symbol),
        "ERC721Consecutive: can't mint during construction",
      );
    });

    it('consecutive mint not compatible with enumerability', async function () {
      await expectRevert(
        ERC721ConsecutiveEnumerableMock.new(
          name,
          symbol,
          batches.map(({ receiver }) => receiver),
          batches.map(({ amount }) => amount),
        ),
        'ERC721Enumerable: consecutive transfers not supported',
      );
    });
  });
});