/**
 * Chain adapter for Tezos mainnet (chainId 1729).
 * Uses TzKT API for read operations. sendTransaction requires Taquito/injection for production.
 */

import type {
  IChainAdapter,
  ChainAdapterConfig,
  NormalizedReceipt,
  NormalizedLog,
  SendTransactionResult,
} from './types.js';
import { getChainConfig, TEZOS_CHAIN_ID } from './config.js';

const TZKt_BASE = 'https://api.tzkt.io';

export class TezosChainAdapter implements IChainAdapter {
  private config: ChainAdapterConfig;
  private baseUrl: string;

  constructor(rpcUrls?: string[]) {
    const cfg = getChainConfig(TEZOS_CHAIN_ID);
    if (!cfg) throw new Error('Tezos chain config not found');
    this.config = rpcUrls?.length ? { ...cfg, rpcUrls } : cfg;
    this.baseUrl = this.config.rpcUrls[0].replace(/\/$/, '');
  }

  getChainId(): number {
    return this.config.chainId;
  }

  getConfig(): ChainAdapterConfig {
    return this.config;
  }

  async getBlockNumber(): Promise<number> {
    const res = await fetch(`${this.baseUrl}/v1/blocks/count`);
    if (!res.ok) throw new Error(`TzKT blocks/count failed: ${res.status}`);
    const count = await res.json();
    return Number(count);
  }

  async getBlock(blockNumber: number): Promise<{ number: number; hash: string; parentHash: string; timestamp: number } | null> {
    const res = await fetch(`${this.baseUrl}/v1/blocks/${blockNumber}`);
    if (!res.ok) return null;
    const b = await res.json();
    return {
      number: b.level,
      hash: b.hash ?? '',
      parentHash: b.previousHash ?? '',
      timestamp: new Date(b.timestamp).getTime() / 1000,
    };
  }

  async sendTransaction(signedTxHex: string): Promise<SendTransactionResult> {
    const hex = signedTxHex.startsWith('0x') ? signedTxHex.slice(2) : signedTxHex;
    const bytes = Buffer.from(hex, 'hex');
    const rpcUrl = process.env.TEZOS_RPC_INJECT_URL ?? 'https://mainnet.api.tez.ie';
    const res = await fetch(`${rpcUrl}/injection/operation`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/octet-stream' },
      body: bytes,
      signal: AbortSignal.timeout(15000),
    });
    if (!res.ok) {
      const err = await res.text();
      throw new Error(`Tezos injection failed: ${res.status} ${err}`);
    }
    const opHash = await res.text();
    return { hash: opHash.trim(), from: '', nonce: 0 };
  }

  async getTransactionReceipt(txHash: string): Promise<NormalizedReceipt | null> {
    const res = await fetch(`${this.baseUrl}/v1/operations/transactions/${txHash}`);
    if (!res.ok) return null;
    const op = await res.json();
    if (Array.isArray(op)) {
      const t = op[0];
      if (!t) return null;
      return {
        chainId: this.config.chainId,
        transactionHash: t.hash,
        blockNumber: BigInt(t.level ?? 0),
        blockHash: t.block ?? '',
        transactionIndex: 0,
        from: t.sender?.address ?? '',
        to: t.target?.address ?? null,
        gasUsed: BigInt(t.gasUsed ?? 0),
        cumulativeGasUsed: BigInt(t.gasUsed ?? 0),
        contractAddress: t.target?.address ?? null,
        logsBloom: '',
        status: t.status === 'applied' ? 1 : 0,
        root: null,
      };
    }
    return {
      chainId: this.config.chainId,
      transactionHash: op.hash,
      blockNumber: BigInt(op.level ?? 0),
      blockHash: op.block ?? '',
      transactionIndex: 0,
      from: op.sender?.address ?? '',
      to: op.target?.address ?? null,
      gasUsed: BigInt(op.gasUsed ?? 0),
      cumulativeGasUsed: BigInt(op.gasUsed ?? 0),
      contractAddress: op.target?.address ?? null,
      logsBloom: '',
      status: op.status === 'applied' ? 1 : 0,
      root: null,
    };
  }

  async getLogs(
    _fromBlock: number,
    _toBlock: number,
    _address?: string,
    _topics?: string[]
  ): Promise<NormalizedLog[]> {
    return [];
  }

  async detectReorg(blockNumber: number, expectedBlockHash: string): Promise<boolean> {
    const block = await this.getBlock(blockNumber);
    if (!block) return true;
    return block.hash !== expectedBlockHash;
  }

  async healthCheck(): Promise<boolean> {
    try {
      await fetch(`${this.baseUrl}/v1/blocks/head`);
      return true;
    } catch {
      return false;
    }
  }
}

export function createAdapterTezos(rpcUrls?: string[]): TezosChainAdapter {
  return new TezosChainAdapter(rpcUrls);
}