import { getBtc2StacksFeeInfo } from "../bitcoinUtils/peggingHelpers"
import { getStacks2EvmFeeInfo } from "../evmUtils/peggingHelpers"
import { BigNumber } from "../utils/BigNumber"
import {
  KnownRoute,
  KnownRoute_FromBitcoin_ToEVM,
  KnownRoute_FromBitcoin_ToStacks,
} from "../utils/buildSupportedRoutes"
import { UnsupportedBridgeRouteError } from "../utils/errors"
import { assertExclude, checkNever } from "../utils/typeHelpers"
import {
  PublicTransferProphetAggregated,
  transformToPublicTransferProphet,
  transformToPublicTransferProphetAggregated,
} from "../utils/types/TransferProphet"
import { KnownChainId, KnownTokenId } from "../utils/types/knownIds"
import { supportedRoutes } from "./bridgeFromBitcoin"
import { ChainId, SDKNumber, TokenId } from "./types"
import { SDKGlobalContext } from "./types.internal"

export interface BridgeInfoFromBitcoinInput {
  fromChain: ChainId
  toChain: ChainId
  fromToken: TokenId
  toToken: TokenId
  amount: SDKNumber
}

export interface BridgeInfoFromBitcoinOutput
  extends PublicTransferProphetAggregated {}

export const bridgeInfoFromBitcoin = async (
  ctx: SDKGlobalContext,
  info: BridgeInfoFromBitcoinInput,
): Promise<BridgeInfoFromBitcoinOutput> => {
  const route = await supportedRoutes.checkRouteValid(ctx, info)

  if (KnownChainId.isBitcoinChain(route.fromChain)) {
    if (KnownChainId.isStacksChain(route.toChain)) {
      if (
        KnownTokenId.isBitcoinToken(route.fromToken) &&
        KnownTokenId.isStacksToken(route.toToken)
      ) {
        return bridgeInfoFromBitcoin_toStacks({
          ...info,
          fromChain: route.fromChain,
          toChain: route.toChain,
          fromToken: route.fromToken,
          toToken: route.toToken,
        })
      }
    } else if (KnownChainId.isEVMChain(route.toChain)) {
      if (
        KnownTokenId.isBitcoinToken(route.fromToken) &&
        KnownTokenId.isEVMToken(route.toToken)
      ) {
        return bridgeInfoFromBitcoin_toEVM({
          ...info,
          fromChain: route.fromChain,
          toChain: route.toChain,
          fromToken: route.fromToken,
          toToken: route.toToken,
        })
      }
    } else if (
      KnownChainId.isBRC20Chain(route.toChain) ||
      KnownChainId.isRunesChain(route.toChain)
    ) {
      assertExclude(route.toChain, assertExclude.i<KnownChainId.BRC20Chain>())
      assertExclude(route.toChain, assertExclude.i<KnownChainId.RunesChain>())
      // TODO: bitcoin to brc20/runes is not supported yet
    } else {
      assertExclude(route.toChain, assertExclude.i<KnownChainId.BitcoinChain>())
      checkNever(route)
    }
  } else {
    assertExclude(route.fromChain, assertExclude.i<KnownChainId.StacksChain>())
    assertExclude(route.fromChain, assertExclude.i<KnownChainId.EVMChain>())
    checkNever(route)
  }

  throw new UnsupportedBridgeRouteError(
    info.fromChain,
    info.toChain,
    info.fromToken,
    info.toToken,
  )
}

async function bridgeInfoFromBitcoin_toStacks(
  info: Omit<
    BridgeInfoFromBitcoinInput,
    "fromChain" | "toChain" | "fromToken" | "toToken"
  > &
    KnownRoute_FromBitcoin_ToStacks,
): Promise<BridgeInfoFromBitcoinOutput> {
  const step1 = await getBtc2StacksFeeInfo(info)
  if (step1 == null) {
    throw new UnsupportedBridgeRouteError(
      info.fromChain,
      info.toChain,
      info.fromToken,
      info.toToken,
    )
  }

  return {
    ...transformToPublicTransferProphet(info, info.amount, step1),
    transferProphets: [],
  }
}

async function bridgeInfoFromBitcoin_toEVM(
  info: Omit<
    BridgeInfoFromBitcoinInput,
    "fromChain" | "toChain" | "fromToken" | "toToken"
  > &
    KnownRoute_FromBitcoin_ToEVM,
): Promise<BridgeInfoFromBitcoinOutput> {
  const transitStacksChainId =
    info.fromChain === KnownChainId.Bitcoin.Mainnet
      ? KnownChainId.Stacks.Mainnet
      : KnownChainId.Stacks.Testnet

  const step1Route: KnownRoute = {
    fromChain: info.fromChain,
    fromToken: KnownTokenId.Bitcoin.BTC,
    toChain: transitStacksChainId,
    toToken: KnownTokenId.Stacks.aBTC,
  }
  const step2Route: KnownRoute = {
    fromChain: transitStacksChainId,
    fromToken: KnownTokenId.Stacks.aBTC,
    toChain: info.toChain,
    toToken: info.toToken,
  }

  const [step1, step2] = await Promise.all([
    getBtc2StacksFeeInfo(step1Route),
    getStacks2EvmFeeInfo(step2Route),
  ])
  if (step1 == null || step2 == null) {
    throw new UnsupportedBridgeRouteError(
      info.fromChain,
      info.toChain,
      info.fromToken,
      info.toToken,
    )
  }

  const step1TransferProphet = transformToPublicTransferProphet(
    step1Route,
    info.amount,
    step1,
  )
  const step2TransferProphet = transformToPublicTransferProphet(
    step2Route,
    step1TransferProphet.toAmount,
    step2,
  )

  return {
    ...transformToPublicTransferProphetAggregated(
      [step1TransferProphet, step2TransferProphet],
      [BigNumber.ONE],
    ),
    transferProphets: [step1TransferProphet, step2TransferProphet],
  }
}