// SPDX-FileCopyrightText: © 2026 LEDGER SAS
// SPDX-License-Identifier: Apache-2.0

import type { TezosCoinConfig, TezosContext } from '../config'
import type { AccountsGetOperationsOptions } from '../network/types'
import type { Operation } from '@ledgerhq/coin-module-framework/api/types'
import { log } from '@ledgerhq/logs'
import { STAKING_ACTION_TO_OP_TYPE } from '../constants'
import { createTzktApi } from '../network'
import {
  type APIDelegationType,
  type APIOperation,
  type APIOriginationType,
  type APIRevealType,
  type APIStakingType,
  type APITokenTransfer,
  type APITransactionType,
  isAPIDelegationType,
  isAPIOriginationType,
  isAPIRevealType,
  isAPIStakingType,
  isAPITransactionType,
  type TokenTransfersGetOptions,
} from '../network/types'

/** Block-level boundary + optional per-stream id cursors for intra-level continuation. */
type ListOperationsCursor = {
  lastLevel: number
  nativeLastId?: number
  tokenLastId?: number
}

function parseCursor(token?: string): ListOperationsCursor | undefined {
  if (!token) return undefined
  try {
    const parsed: unknown = JSON.parse(token)
    if (parsed && typeof parsed === 'object' && !Array.isArray(parsed)) {
      const o = parsed as {
        lastLevel?: unknown
        nativeLastId?: unknown
        tokenLastId?: unknown
      }
      if (typeof o.lastLevel === 'number' && Number.isFinite(o.lastLevel)) {
        const cursor: ListOperationsCursor = { lastLevel: o.lastLevel }
        if (typeof o.nativeLastId === 'number' && Number.isFinite(o.nativeLastId)) {
          cursor.nativeLastId = o.nativeLastId
        }
        if (typeof o.tokenLastId === 'number' && Number.isFinite(o.tokenLastId)) {
          cursor.tokenLastId = o.tokenLastId
        }
        return cursor
      }
    }
  } catch {
    // ignore invalid cursor
  }
  return undefined
}

function minLevel<T extends { level: number }>(items: T[]): number | undefined {
  if (items.length === 0) return undefined
  return Math.min(...items.map((i) => i.level))
}

function maxLevel<T extends { level: number }>(items: T[]): number | undefined {
  if (items.length === 0) return undefined
  return Math.max(...items.map((i) => i.level))
}

/** When the API returned a full page, the trailing block level may be incomplete — drop it. */
function trimPartialLastLevel<T extends { level: number; id: number }>(
  items: T[],
  full: boolean
): { trimmed: T[]; intraLevelLastId?: number } {
  if (!full || items.length === 0) return { trimmed: items }
  const last = items.at(-1)
  if (!last) return { trimmed: items }
  const lastLevel = last.level
  const filtered = items.filter((op) => op.level !== lastLevel)
  if (filtered.length === 0) {
    log('coin:tezos', 'listOperations: full page single level — keeping all rows', {
      lastLevel,
      count: items.length,
    })
    return { trimmed: items, intraLevelLastId: last.id }
  }
  return { trimmed: filtered }
}

function buildNativeOptions(
  sort: 'Ascending' | 'Descending',
  cursor: ListOperationsCursor | undefined,
  minHeight: number
): AccountsGetOperationsOptions {
  if (!cursor) {
    return { sort, 'level.ge': minHeight }
  }

  const { lastLevel, nativeLastId } = cursor

  if (sort === 'Descending') {
    if (nativeLastId !== undefined) {
      return {
        sort,
        'level.ge': minHeight,
        'level.lt': lastLevel + 1,
        lastId: nativeLastId,
      }
    }
    return {
      sort,
      'level.ge': minHeight,
      'level.lt': lastLevel,
    }
  }

  if (nativeLastId !== undefined) {
    return {
      sort,
      'level.ge': Math.max(minHeight, lastLevel),
      lastId: nativeLastId,
    }
  }
  return {
    sort,
    'level.ge': Math.max(minHeight, lastLevel + 1),
  }
}

function buildTokenOptions(
  sort: 'Ascending' | 'Descending',
  cursor: ListOperationsCursor | undefined,
  minHeight: number
): TokenTransfersGetOptions {
  if (!cursor) {
    return { sort, 'level.ge': minHeight }
  }

  const { lastLevel, tokenLastId } = cursor

  if (sort === 'Descending') {
    if (tokenLastId !== undefined) {
      return {
        sort,
        'level.ge': minHeight,
        'level.lt': lastLevel + 1,
        'id.lt': tokenLastId,
      }
    }
    return {
      sort,
      'level.ge': minHeight,
      'level.lt': lastLevel,
    }
  }

  if (tokenLastId !== undefined) {
    return {
      sort,
      'level.ge': Math.max(minHeight, lastLevel),
      'id.gt': tokenLastId,
    }
  }
  return {
    sort,
    'level.ge': Math.max(minHeight, lastLevel + 1),
  }
}

function computeBoundary(
  nativeTrim: { level: number }[],
  tokenTrim: { level: number }[],
  sort: 'Ascending' | 'Descending'
): number | undefined {
  if (sort === 'Descending') {
    const mn = minLevel(nativeTrim)
    const mt = minLevel(tokenTrim)
    if (mn === undefined && mt === undefined) return undefined
    if (mn === undefined) return mt!
    if (mt === undefined) return mn
    return Math.max(mn, mt)
  }
  const xn = maxLevel(nativeTrim)
  const xt = maxLevel(tokenTrim)
  if (xn === undefined && xt === undefined) return undefined
  if (xn === undefined) return xt!
  if (xt === undefined) return xn
  return Math.min(xn, xt)
}

function alignToBoundary<T extends { level: number }>(
  items: T[],
  boundary: number,
  sort: 'Ascending' | 'Descending'
): T[] {
  if (sort === 'Descending') {
    return items.filter((op) => op.level >= boundary)
  }
  return items.filter((op) => op.level <= boundary)
}

function clampPage<T>(raw: T[], limit?: number): { sliced: T[]; full: boolean } {
  if (limit === undefined) {
    return { sliced: raw, full: false }
  }
  return {
    sliced: raw.slice(0, limit),
    full: raw.length >= limit,
  }
}

function buildParentMap(ops: APIOperation[]): Map<number, APITransactionType> {
  const parentMap = new Map<number, APITransactionType>()
  for (const op of ops) {
    if (isAPITransactionType(op) && op.id !== null) {
      parentMap.set(op.id, op)
    }
  }
  return parentMap
}

function keepNativeOp(op: APIOperation, address: string): op is ConvertibleOperation {
  if (
    !(
      isAPITransactionType(op) ||
      isAPIDelegationType(op) ||
      isAPIRevealType(op) ||
      isAPIStakingType(op) ||
      isAPIOriginationType(op)
    )
  ) {
    return false
  }
  if (op.status !== 'applied' && isAPITransactionType(op)) {
    const isIn = op.target?.address === address
    if (isIn) {
      return false
    }
  }
  // Filter out internal (contract-to-contract/contract-to-third-party) transactions:
  // TzKT returns these under the initiator's account, but they don't impact the
  // initiator's native balance — the top-level operation already accounts for it.
  if (isAPITransactionType(op)) {
    const isSender = op.sender?.address === address
    const isTarget = op.target?.address === address
    if (!isSender && !isTarget) {
      return false
    }
  }
  return true
}

function convertNativeOps(
  ops: APIOperation[],
  address: string,
  stakingBlockHashes: Map<number, string>
): Operation[] {
  // Accumulate fees from internal sub-txs that will be filtered out.
  // On Tezos, when an account initiates a contract call, internal sub-operations
  // may incur storage/baker fees charged to the initiator. These sub-txs are
  // filtered by keepNativeOp (account is neither sender nor target), but their
  // fees still impact the initiator's balance and must be attributed to the
  // top-level operation.
  const internalFeesByHash = new Map<string, bigint>()
  for (const op of ops) {
    if (
      isAPITransactionType(op) &&
      op.initiator?.address === address &&
      op.sender?.address !== address &&
      op.target?.address !== address
    ) {
      const hash = op.hash
      if (!hash) continue
      const fee =
        BigInt(op.storageFee ?? 0) + BigInt(op.bakerFee ?? 0) + BigInt(op.allocationFee ?? 0)
      if (fee > 0n) {
        internalFeesByHash.set(hash, (internalFeesByHash.get(hash) ?? 0n) + fee)
      }
    }
  }

  return ops
    .filter((op): op is ConvertibleOperation => keepNativeOp(op, address))
    .map((op) => {
      const converted = convertOperation(address, op, stakingBlockHashes)
      const extraFee = internalFeesByHash.get(converted.tx.hash)
      if (extraFee) {
        // Add internal sub-tx fees to the parent operation, then clear to avoid
        // attributing the same fees to multiple ops sharing the same hash.
        internalFeesByHash.delete(converted.tx.hash)
        return { ...converted, tx: { ...converted.tx, fees: converted.tx.fees + extraFee } }
      }
      return converted
    })
}

function convertTokenOps(
  transfers: (APITokenTransfer & { hash: string; block?: string })[],
  parentMap: Map<number, APITransactionType>,
  address: string
): Operation[] {
  return transfers.map((transfer) =>
    convertTokenOperation(
      address,
      transfer,
      transfer.transactionId ? parentMap.get(transfer.transactionId) : undefined
    )
  )
}

function computeNextToken(
  boundary: number | undefined,
  nativeFull: boolean,
  tokenFull: boolean,
  hasResults: boolean,
  nativeIntraLastId?: number,
  tokenIntraLastId?: number
): string {
  const shouldEmitNext = boundary !== undefined && (nativeFull || tokenFull) && hasResults
  if (!shouldEmitNext) return ''
  const payload: ListOperationsCursor = { lastLevel: boundary }
  if (nativeIntraLastId !== undefined) payload.nativeLastId = nativeIntraLastId
  if (tokenIntraLastId !== undefined) payload.tokenLastId = tokenIntraLastId
  return JSON.stringify(payload)
}

/**
 * Returns list of "Transfer", "Delegate" and "Undelegate" Operations associated to an account.
 * @param address Account address
 * @param limit the maximum number of operations to return. Beware that's a weak limit, as explorers might not respect it.
 * @param order whether to return operations starting from the top block or from the oldest block.
 *   "Descending" returns newest operation first, "Ascending" returns oldest operation first.
 *   It doesn't control the order of the operations in the result list:
 *     operations are always returned sorted in descending order (newest first).
 * @param minHeight retrieve operations from a specific block height until top most (inclusive).
 * @param token a token to be used for pagination
 * @returns a list of operations is descending (newest first) order and a token to be used for pagination
 */
export async function listOperations(
  context: TezosContext,
  address: string,
  {
    token,
    limit,
    sort,
    minHeight,
  }: { limit?: number; token?: string; sort: 'Ascending' | 'Descending'; minHeight: number }
): Promise<[Operation[], string]> {
  const config = await context.config()
  const tzkt = createTzktApi(config)
  const cursor = parseCursor(token)

  const nativeOptions: AccountsGetOperationsOptions = {
    limit,
    ...buildNativeOptions(sort, cursor, minHeight),
  }

  const tokenOptions: TokenTransfersGetOptions = {
    limit,
    ...buildTokenOptions(sort, cursor, minHeight),
  }

  const [nativeOpsRaw, tokenTransfersRaw] = await Promise.all([
    tzkt.getAccountOperations(address, nativeOptions),
    tzkt.getAccountTokenTransfers(address, tokenOptions),
  ])

  const nativePage = clampPage(nativeOpsRaw, limit)
  const tokenPage = clampPage(tokenTransfersRaw, limit)

  const nativeTrimmed = trimPartialLastLevel(nativePage.sliced, nativePage.full)
  const tokenTrimmed = trimPartialLastLevel(tokenPage.sliced, tokenPage.full)

  // when both streams are exhausted (neither hit the page limit),
  // we already have every op — alignment would silently discard ops
  // beyond the boundary with no cursor to retrieve them later. Skip it.
  const bothExhausted = !nativePage.full && !tokenPage.full
  const boundary = bothExhausted
    ? undefined
    : computeBoundary(nativeTrimmed.trimmed, tokenTrimmed.trimmed, sort)

  const nativeAligned =
    boundary === undefined
      ? nativeTrimmed.trimmed
      : alignToBoundary(nativeTrimmed.trimmed, boundary, sort)
  const tokenAligned =
    boundary === undefined
      ? tokenTrimmed.trimmed
      : alignToBoundary(tokenTrimmed.trimmed, boundary, sort)

  const stakingBlockHashes = await fetchMissingStakingBlockHashes(config, nativeAligned)

  const parentMap = buildParentMap(nativeAligned)

  const nextToken = computeNextToken(
    boundary,
    nativePage.full,
    tokenPage.full,
    nativeAligned.length > 0 || tokenAligned.length > 0,
    nativeTrimmed.intraLevelLastId,
    tokenTrimmed.intraLevelLastId
  )

  const filteredNativeOps = convertNativeOps(nativeAligned, address, stakingBlockHashes)
  const tokenConverted = convertTokenOps(tokenAligned, parentMap, address)

  const sortedOperations = [...filteredNativeOps, ...tokenConverted].sort(
    (a, b) => b.tx.date.getTime() - a.tx.date.getTime()
  )
  return [sortedOperations, nextToken]
}

type ConvertibleOperation =
  | APITransactionType
  | APIDelegationType
  | APIRevealType
  | APIStakingType
  | APIOriginationType

/**
 * TzKT omits `block` on staking ops returned by /accounts/{addr}/operations.
 * Returns a level → block-hash map covering exactly those ops, so the caller
 * can populate `tx.block.hash` without mutating the API response. Network
 * failures are swallowed: callers fall back to `""` for levels not in the map.
 */
async function fetchMissingStakingBlockHashes(
  config: TezosCoinConfig,
  ops: readonly APIOperation[]
): Promise<Map<number, string>> {
  const missingLevels = new Set<number>()
  for (const op of ops) {
    if (isAPIStakingType(op) && !op.block) missingLevels.add(op.level)
  }
  if (missingLevels.size === 0) return new Map()
  try {
    return await createTzktApi(config).getBlockHashesByLevels([...missingLevels])
  } catch (err) {
    log('coin:tezos', 'fetchMissingStakingBlockHashes: skipped on fetch error', {
      reason: String(err),
    })
    return new Map()
  }
}

function resolveBlockHash(
  operation: ConvertibleOperation,
  stakingBlockHashes: Map<number, string>
): string {
  const fromOp = typeof operation.block === 'string' ? operation.block : operation.block?.hash
  return fromOp ?? stakingBlockHashes.get(operation.level) ?? ''
}

function resolveTargetAddress(operation: ConvertibleOperation): string | undefined {
  if (isAPITransactionType(operation)) return operation.target?.address
  if (isAPIOriginationType(operation)) return operation.originatedContract?.address
  if (isAPIDelegationType(operation)) {
    return operation.newDelegate?.address || operation.prevDelegate?.address
  }
  if (isAPIStakingType(operation)) return operation.baker?.address
  return undefined
}

// finalize_unstake's protocol sender is the gas payer (anyone may call it),
// not the staker; map staking ops from the staker's perspective so the op
// stays visible in their wallet.
function resolveStakingAddresses(op: APIStakingType): {
  senders: string[]
  recipients: string[]
} {
  const stakerAddr = op.staker?.address ?? op.sender?.address
  const bakerAddr = op.baker?.address
  const stakerArr = stakerAddr ? [stakerAddr] : []
  const bakerArr = bakerAddr ? [bakerAddr] : []
  if (op.action === 'finalize') return { senders: bakerArr, recipients: stakerArr }
  return { senders: stakerArr, recipients: bakerArr }
}

// Failed stake/unstake ops carry `requestedAmount` and no `amount` field;
// `BigInt(undefined)` throws and breaks sync. Fall back per-shape.
function resolveAmount(operation: ConvertibleOperation): bigint {
  if (isAPIRevealType(operation) || isAPIDelegationType(operation)) return 0n
  if (isAPIOriginationType(operation)) return BigInt(operation.contractBalance ?? 0)
  if (isAPIStakingType(operation)) {
    return BigInt(operation.amount ?? operation.requestedAmount ?? 0)
  }
  return BigInt(operation.amount ?? 0)
}

function resolveNormalizedType(
  operation: ConvertibleOperation,
  address: string,
  targetAddress: string | undefined,
  amount: bigint
): Operation['type'] {
  if (isAPIDelegationType(operation)) {
    return operation.newDelegate?.address ? 'DELEGATE' : 'UNDELEGATE'
  }
  if (isAPIStakingType(operation)) return STAKING_ACTION_TO_OP_TYPE[operation.action]
  if (isAPIRevealType(operation)) return 'REVEAL'
  if (isAPIOriginationType(operation)) return operation.contractBalance > 0 ? 'OUT' : 'FEES'
  if (!isAPITransactionType(operation)) {
    log('coin:tezos', '(logic/operations): Unknown operation type, defaulting to OUT')
    return 'OUT'
  }
  const isOut = operation.sender?.address === address
  const isIn = targetAddress === address
  if ((isOut && isIn) || amount === 0n) return 'FEES'
  if (isOut) return 'OUT'
  if (isIn) return 'IN'
  return 'OUT'
}

function getLedgerOpType(
  operation: ConvertibleOperation,
  normalizedType: Operation['type']
): string | undefined {
  if (isAPIDelegationType(operation)) {
    return operation.newDelegate?.address ? 'DELEGATE' : 'UNDELEGATE'
  } else if (isAPIRevealType(operation)) {
    return 'REVEAL'
  } else if (isAPIOriginationType(operation)) {
    return 'ORIGINATION'
  } else if (isAPIStakingType(operation)) {
    return STAKING_ACTION_TO_OP_TYPE[operation.action]
  } else if (normalizedType === 'FEES') {
    return 'FEES'
  }
  return undefined
}

function convertOperation(
  address: string,
  operation: ConvertibleOperation,
  stakingBlockHashes: Map<number, string>
): Operation {
  const { hash, sender, id } = operation

  // For transactions, the initiator (if present) is the fee payer (internal/sub-operations triggered by contracts).
  // Otherwise, the sender is the fee payer. For delegation/reveal/staking there is no initiator; sender is the fee payer.
  const feesPayer = isAPITransactionType(operation)
    ? (operation.initiator?.address ?? sender?.address)
    : sender?.address

  const targetAddress = resolveTargetAddress(operation)
  // reveal has no meaningful target; staking resolves senders/recipients separately.
  if (!targetAddress && !isAPIRevealType(operation) && !isAPIStakingType(operation)) {
    log('coin:tezos', '(logic/operations): No target address found for operation', operation)
  }

  const { senders, recipients } = isAPIStakingType(operation)
    ? resolveStakingAddresses(operation)
    : {
        senders: sender?.address ? [sender.address] : [],
        recipients: targetAddress ? [targetAddress] : [],
      }

  const amount = resolveAmount(operation)

  const fee =
    BigInt(operation.storageFee ?? 0) +
    BigInt(operation.bakerFee ?? 0) +
    BigInt(operation.allocationFee ?? 0)

  const normalizedType = resolveNormalizedType(operation, address, targetAddress, amount)

  // Tezos uses "applied" for every success operation (something else=failed )
  const hasFailed = operation.status && operation.status !== 'applied'

  return {
    id: `${hash ?? ''}-${id}`,
    asset: { type: 'native' },
    tx: {
      // hash id defined nullable in the tzkt API, but I wonder when it would be null ?
      hash: hash ?? '',
      // storageFee for transaction is always present
      fees: BigInt(fee ?? 0),
      ...(feesPayer ? { feesPayer } : {}),
      block: {
        hash: resolveBlockHash(operation, stakingBlockHashes),
        height: operation.level,
        time: new Date(operation.timestamp),
      },
      date: new Date(operation.timestamp),
      failed: hasFailed ?? false,
    },
    type: normalizedType,
    value: amount,
    senders: senders,
    recipients: recipients,
    details: {
      counter: operation.counter,
      gasLimit: operation.gasLimit,
      storageLimit: operation.storageLimit,
      ledgerOpType: getLedgerOpType(operation, normalizedType),
    },
  }
}

function convertTokenOperation(
  address: string,
  transfer: APITokenTransfer & { hash: string; block?: string },
  parent?: APITransactionType
): Operation {
  const isOut = transfer.from?.address === address
  const isIn = transfer.to?.address === address
  let type: Operation['type'] = 'FEES'
  if (isOut && !isIn) {
    type = 'OUT'
  } else if (isIn && !isOut) {
    type = 'IN'
  }

  const feesPayer = parent?.initiator?.address ?? parent?.sender?.address

  const tokenId = transfer.token.tokenId ?? '0'
  const assetReference = `${transfer.token.contract.address}:${tokenId}`

  return {
    id: `${transfer.hash}-token-${transfer.id}`,
    type,
    senders: transfer.from?.address ? [transfer.from.address] : [],
    recipients: transfer.to?.address ? [transfer.to.address] : [],
    value: BigInt(transfer.amount),
    asset: {
      type: transfer.token.standard,
      assetReference,
      assetOwner: address,
      unit: {
        magnitude: Number.parseInt(transfer.token.metadata?.decimals ?? '0', 10),
        name: transfer.token.metadata?.name ?? '',
        code: transfer.token.metadata?.symbol ?? '',
      },
    },
    tx: {
      hash: transfer.hash,
      // Fee is already on the parent native operation; setting 0 avoids
      // double-counting when A4 sums fees across sub-operations (FeeAggregationMode.Sum).
      fees: 0n,
      ...(feesPayer ? { feesPayer } : {}),
      block: {
        hash: transfer.block ?? parent?.block ?? '',
        height: transfer.level,
        time: new Date(transfer.timestamp),
      },
      date: new Date(transfer.timestamp),
      failed: parent ? Boolean(parent.status && parent.status !== 'applied') : false,
    },
    details: {
      ledgerOpType: type,
      assetAmount: transfer.amount,
      assetSenders: transfer.from?.address ? [transfer.from.address] : [],
      assetRecipients: transfer.to?.address ? [transfer.to.address] : [],
      parentSenders: parent?.sender?.address ? [parent.sender.address] : [],
      parentRecipients: parent?.target?.address ? [parent.target.address] : [],
    },
  }
}