import { ZeroEx } from '0x.js';
import { BigNumber } from '@0xproject/utils';
import * as _ from 'lodash';
import {
    Action,
    ActionTypes,
    BlockchainErrs,
    Order,
    ProviderType,
    ScreenWidths,
    Side,
    SideToAssetToken,
    SignatureData,
    TokenByAddress,
    TokenState,
    TokenStateByAddress,
} from 'ts/types';
import { utils } from 'ts/utils/utils';

// Instead of defaulting the docs version to an empty string, we pre-populate it with
// a valid version value. This does not need to be updated however, since onLoad, it
// is always replaced with a value retrieved from our S3 bucket.
const DEFAULT_DOCS_VERSION = '0.0.0';

export interface State {
    // Portal
    blockchainErr: BlockchainErrs;
    blockchainIsLoaded: boolean;
    networkId: number;
    orderExpiryTimestamp: BigNumber;
    orderFillAmount: BigNumber;
    orderTakerAddress: string;
    orderSignatureData: SignatureData;
    orderSalt: BigNumber;
    nodeVersion: string;
    screenWidth: ScreenWidths;
    shouldBlockchainErrDialogBeOpen: boolean;
    sideToAssetToken: SideToAssetToken;
    tokenByAddress: TokenByAddress;
    tokenStateByAddress: TokenStateByAddress;
    userAddress: string;
    userEtherBalance: BigNumber;
    // Note: cache of supplied orderJSON in fill order step. Do not use for anything else.
    userSuppliedOrderCache: Order;

    // Docs
    docsVersion: string;
    availableDocVersions: string[];

    // Shared
    flashMessage: string | React.ReactNode;
    providerType: ProviderType;
    injectedProviderName: string;
}

const INITIAL_STATE: State = {
    // Portal
    blockchainErr: BlockchainErrs.NoError,
    blockchainIsLoaded: false,
    networkId: undefined,
    orderExpiryTimestamp: utils.initialOrderExpiryUnixTimestampSec(),
    orderFillAmount: undefined,
    orderSignatureData: {
        hash: '',
        r: '',
        s: '',
        v: 27,
    },
    orderTakerAddress: '',
    orderSalt: ZeroEx.generatePseudoRandomSalt(),
    nodeVersion: undefined,
    screenWidth: utils.getScreenWidth(),
    shouldBlockchainErrDialogBeOpen: false,
    sideToAssetToken: {
        [Side.Deposit]: {},
        [Side.Receive]: {},
    },
    tokenByAddress: {},
    tokenStateByAddress: {},
    userAddress: '',
    userEtherBalance: new BigNumber(0),
    userSuppliedOrderCache: undefined,

    // Docs
    docsVersion: DEFAULT_DOCS_VERSION,
    availableDocVersions: [DEFAULT_DOCS_VERSION],

    // Shared
    flashMessage: undefined,
    providerType: ProviderType.Injected,
    injectedProviderName: '',
};

export function reducer(state: State = INITIAL_STATE, action: Action) {
    switch (action.type) {
        // Portal
        case ActionTypes.ResetState:
            return INITIAL_STATE;

        case ActionTypes.UpdateOrderSalt: {
            return {
                ...state,
                orderSalt: action.data,
            };
        }

        case ActionTypes.UpdateNodeVersion: {
            return {
                ...state,
                nodeVersion: action.data,
            };
        }

        case ActionTypes.UpdateOrderFillAmount: {
            return {
                ...state,
                orderFillAmount: action.data,
            };
        }

        case ActionTypes.UpdateShouldBlockchainErrDialogBeOpen: {
            return {
                ...state,
                shouldBlockchainErrDialogBeOpen: action.data,
            };
        }

        case ActionTypes.UpdateUserEtherBalance: {
            return {
                ...state,
                userEtherBalance: action.data,
            };
        }

        case ActionTypes.UpdateUserSuppliedOrderCache: {
            return {
                ...state,
                userSuppliedOrderCache: action.data,
            };
        }

        case ActionTypes.ClearTokenByAddress: {
            return {
                ...state,
                tokenByAddress: {},
            };
        }

        case ActionTypes.AddTokenToTokenByAddress: {
            const newTokenByAddress = state.tokenByAddress;
            newTokenByAddress[action.data.address] = action.data;
            return {
                ...state,
                tokenByAddress: newTokenByAddress,
            };
        }

        case ActionTypes.RemoveTokenFromTokenByAddress: {
            const newTokenByAddress = state.tokenByAddress;
            delete newTokenByAddress[action.data.address];
            return {
                ...state,
                tokenByAddress: newTokenByAddress,
            };
        }

        case ActionTypes.UpdateTokenByAddress: {
            const tokenByAddress = state.tokenByAddress;
            const tokens = action.data;
            _.each(tokens, token => {
                const updatedToken = {
                    ...tokenByAddress[token.address],
                    ...token,
                };
                tokenByAddress[token.address] = updatedToken;
            });
            return {
                ...state,
                tokenByAddress,
            };
        }

        case ActionTypes.UpdateTokenStateByAddress: {
            const tokenStateByAddress = state.tokenStateByAddress;
            const updatedTokenStateByAddress = action.data;
            _.each(updatedTokenStateByAddress, (tokenState: TokenState, address: string) => {
                const updatedTokenState = {
                    ...tokenStateByAddress[address],
                    ...tokenState,
                };
                tokenStateByAddress[address] = updatedTokenState;
            });
            return {
                ...state,
                tokenStateByAddress,
            };
        }

        case ActionTypes.RemoveFromTokenStateByAddress: {
            const tokenStateByAddress = state.tokenStateByAddress;
            const tokenAddress = action.data;
            delete tokenStateByAddress[tokenAddress];
            return {
                ...state,
                tokenStateByAddress,
            };
        }

        case ActionTypes.ReplaceTokenAllowanceByAddress: {
            const tokenStateByAddress = state.tokenStateByAddress;
            const allowance = action.data.allowance;
            const tokenAddress = action.data.address;
            tokenStateByAddress[tokenAddress] = {
                ...tokenStateByAddress[tokenAddress],
                allowance,
            };
            return {
                ...state,
                tokenStateByAddress,
            };
        }

        case ActionTypes.ReplaceTokenBalanceByAddress: {
            const tokenStateByAddress = state.tokenStateByAddress;
            const balance = action.data.balance;
            const tokenAddress = action.data.address;
            tokenStateByAddress[tokenAddress] = {
                ...tokenStateByAddress[tokenAddress],
                balance,
            };
            return {
                ...state,
                tokenStateByAddress,
            };
        }

        case ActionTypes.UpdateTokenBalanceByAddress: {
            const tokenStateByAddress = state.tokenStateByAddress;
            const balanceDelta = action.data.balanceDelta;
            const tokenAddress = action.data.address;
            const currBalance = tokenStateByAddress[tokenAddress].balance;
            tokenStateByAddress[tokenAddress] = {
                ...tokenStateByAddress[tokenAddress],
                balance: currBalance.plus(balanceDelta),
            };
            return {
                ...state,
                tokenStateByAddress,
            };
        }

        case ActionTypes.UpdateOrderSignatureData: {
            return {
                ...state,
                orderSignatureData: action.data,
            };
        }

        case ActionTypes.UpdateScreenWidth: {
            return {
                ...state,
                screenWidth: action.data,
            };
        }

        case ActionTypes.UpdateBlockchainIsLoaded: {
            return {
                ...state,
                blockchainIsLoaded: action.data,
            };
        }

        case ActionTypes.BlockchainErrEncountered: {
            return {
                ...state,
                blockchainErr: action.data,
            };
        }

        case ActionTypes.UpdateNetworkId: {
            return {
                ...state,
                networkId: action.data,
            };
        }

        case ActionTypes.UpdateChosenAssetToken: {
            const newSideToAssetToken = {
                ...state.sideToAssetToken,
                [action.data.side]: action.data.token,
            };
            return {
                ...state,
                sideToAssetToken: newSideToAssetToken,
            };
        }

        case ActionTypes.UpdateChosenAssetTokenAddress: {
            const newAssetToken = state.sideToAssetToken[action.data.side];
            newAssetToken.address = action.data.address;
            const newSideToAssetToken = {
                ...state.sideToAssetToken,
                [action.data.side]: newAssetToken,
            };
            return {
                ...state,
                sideToAssetToken: newSideToAssetToken,
            };
        }

        case ActionTypes.SwapAssetTokens: {
            const newSideToAssetToken = {
                [Side.Deposit]: state.sideToAssetToken[Side.Receive],
                [Side.Receive]: state.sideToAssetToken[Side.Deposit],
            };
            return {
                ...state,
                sideToAssetToken: newSideToAssetToken,
            };
        }

        case ActionTypes.UpdateOrderExpiry: {
            return {
                ...state,
                orderExpiryTimestamp: action.data,
            };
        }

        case ActionTypes.UpdateOrderTakerAddress: {
            return {
                ...state,
                orderTakerAddress: action.data,
            };
        }

        case ActionTypes.UpdateUserAddress: {
            return {
                ...state,
                userAddress: action.data,
            };
        }

        // Docs
        case ActionTypes.UpdateLibraryVersion: {
            return {
                ...state,
                docsVersion: action.data,
            };
        }
        case ActionTypes.UpdateAvailableLibraryVersions: {
            return {
                ...state,
                availableDocVersions: action.data,
            };
        }

        // Shared
        case ActionTypes.ShowFlashMessage: {
            return {
                ...state,
                flashMessage: action.data,
            };
        }

        case ActionTypes.HideFlashMessage: {
            return {
                ...state,
                flashMessage: undefined,
            };
        }

        case ActionTypes.UpdateProviderType: {
            return {
                ...state,
                providerType: action.data,
            };
        }

        case ActionTypes.UpdateInjectedProviderName: {
            return {
                ...state,
                injectedProviderName: action.data,
            };
        }

        default:
            return state;
    }
}