import path from 'node:path';

import type { Span } from '../trace';
import { surgeDomainsetToClashDomainset } from './clash';
import { compareAndWriteFile, withBannerArray } from './create-file';
import { ipCidrListToSingbox, surgeDomainsetToSingbox } from './singbox';
import { sortDomains } from './stable-sort-domain';
import { createTrie } from './trie';
import { invariant } from 'foxact/invariant';
import { OUTPUT_CLASH_DIR, OUTPUT_SINGBOX_DIR, OUTPUT_SURGE_DIR } from '../constants/dir';
import stringify from 'json-stringify-pretty-compact';
import { appendArrayInPlace } from './append-array-in-place';

abstract class RuleOutput {
  protected domainTrie = createTrie<unknown>(null, true);
  protected domainKeywords = new Set<string>();
  protected domainWildcard = new Set<string>();
  protected ipcidr = new Set<string>();
  protected ipcidrNoResolve = new Set<string>();
  protected ipcidr6 = new Set<string>();
  protected ipcidr6NoResolve = new Set<string>();
  protected otherRules = new Set<string>();
  protected abstract type: 'domainset' | 'non_ip' | 'ip';

  protected pendingPromise = Promise.resolve();

  static jsonToLines(this: void, json: unknown): string[] {
    return stringify(json).split('\n');
  }

  constructor(
    protected readonly span: Span,
    protected readonly id: string
  ) {}

  protected title: string | null = null;
  withTitle(title: string) {
    this.title = title;
    return this;
  }

  protected description: string[] | readonly string[] | null = null;
  withDescription(description: string[] | readonly string[]) {
    this.description = description;
    return this;
  }

  protected date = new Date();
  withDate(date: Date) {
    this.date = date;
    return this;
  }

  protected apexDomainMap: Map<string, string> | null = null;
  protected subDomainMap: Map<string, string> | null = null;
  withDomainMap(apexDomainMap: Map<string, string>, subDomainMap: Map<string, string>) {
    this.apexDomainMap = apexDomainMap;
    this.subDomainMap = subDomainMap;
    return this;
  }

  addDomain(domain: string) {
    this.domainTrie.add(domain);
    return this;
  }

  addDomainSuffix(domain: string) {
    this.domainTrie.add(domain[0] === '.' ? domain : '.' + domain);
    return this;
  }

  bulkAddDomainSuffix(domains: string[]) {
    for (let i = 0, len = domains.length; i < len; i++) {
      this.addDomainSuffix(domains[i]);
    }
    return this;
  }

  addDomainKeyword(keyword: string) {
    this.domainKeywords.add(keyword);
    return this;
  }

  addDomainWildcard(wildcard: string) {
    this.domainWildcard.add(wildcard);
    return this;
  }

  private async addFromDomainsetPromise(source: AsyncIterable<string> | Iterable<string> | string[]) {
    for await (const line of source) {
      if (line[0] === '.') {
        this.addDomainSuffix(line);
      } else {
        this.addDomain(line);
      }
    }
  }

  addFromDomainset(source: AsyncIterable<string> | Iterable<string> | string[]) {
    this.pendingPromise = this.pendingPromise.then(() => this.addFromDomainsetPromise(source));
    return this;
  }

  async addFromRuleset(source: AsyncIterable<string> | Iterable<string>) {
    for await (const line of source) {
      const [type, value, arg] = line.split(',');
      switch (type) {
        case 'DOMAIN':
          this.addDomain(value);
          break;
        case 'DOMAIN-SUFFIX':
          this.addDomainSuffix(value);
          break;
        case 'DOMAIN-KEYWORD':
          this.addDomainKeyword(value);
          break;
        case 'DOMAIN-WILDCARD':
          this.addDomainWildcard(value);
          break;
        case 'IP-CIDR':
          (arg === 'no-resolve' ? this.ipcidrNoResolve : this.ipcidr).add(value);
          break;
        case 'IP-CIDR6':
          (arg === 'no-resolve' ? this.ipcidr6NoResolve : this.ipcidr6).add(value);
          break;
        default:
          this.otherRules.add(line);
          break;
      }
    }
    return this;
  }

  bulkAddCIDR4(cidr: string[]) {
    for (let i = 0, len = cidr.length; i < len; i++) {
      this.ipcidr.add(cidr[i]);
    }
    return this;
  }

  bulkAddCIDR6(cidr: string[]) {
    for (let i = 0, len = cidr.length; i < len; i++) {
      this.ipcidr6.add(cidr[i]);
    }
    return this;
  }

  abstract write(): Promise<void>;
}

export class DomainsetOutput extends RuleOutput {
  protected type = 'domainset' as const;

  async write() {
    await this.pendingPromise;

    invariant(this.title, 'Missing title');
    invariant(this.description, 'Missing description');

    const sorted = sortDomains(this.domainTrie.dump(), this.apexDomainMap, this.subDomainMap);
    sorted.push('this_ruleset_is_made_by_sukkaw.ruleset.skk.moe');

    const surge = sorted;
    const clash = surgeDomainsetToClashDomainset(sorted);
    const singbox = RuleOutput.jsonToLines(surgeDomainsetToSingbox(sorted));

    await Promise.all([
      compareAndWriteFile(
        this.span,
        withBannerArray(
          this.title,
          this.description,
          this.date,
          surge
        ),
        path.join(OUTPUT_SURGE_DIR, this.type, this.id + '.conf')
      ),
      compareAndWriteFile(
        this.span,
        withBannerArray(
          this.title,
          this.description,
          this.date,
          clash
        ),
        path.join(OUTPUT_CLASH_DIR, this.type, this.id + '.txt')
      ),
      compareAndWriteFile(
        this.span,
        singbox,
        path.join(OUTPUT_SINGBOX_DIR, this.type, this.id + '.json')
      )
    ]);
  }
}

export class IPListOutput extends RuleOutput {
  protected type = 'ip' as const;

  constructor(span: Span, id: string, private readonly clashUseRule = true) {
    super(span, id);
  }

  async write() {
    await this.pendingPromise;

    invariant(this.title, 'Missing title');
    invariant(this.description, 'Missing description');

    const sorted4 = Array.from(this.ipcidr);
    const sorted6 = Array.from(this.ipcidr6);
    const merged = appendArrayInPlace(appendArrayInPlace([], sorted4), sorted6);

    const surge = sorted4.map(i => `IP-CIDR,${i}`);
    appendArrayInPlace(surge, sorted6.map(i => `IP-CIDR6,${i}`));
    surge.push('DOMAIN,this_ruleset_is_made_by_sukkaw.ruleset.skk.moe');

    const clash = this.clashUseRule ? surge : merged;
    const singbox = RuleOutput.jsonToLines(ipCidrListToSingbox(merged));

    await Promise.all([
      compareAndWriteFile(
        this.span,
        withBannerArray(
          this.title,
          this.description,
          this.date,
          surge
        ),
        path.join(OUTPUT_SURGE_DIR, this.type, this.id + '.conf')
      ),
      compareAndWriteFile(
        this.span,
        withBannerArray(
          this.title,
          this.description,
          this.date,
          clash
        ),
        path.join(OUTPUT_CLASH_DIR, this.type, this.id + '.txt')
      ),
      compareAndWriteFile(
        this.span,
        singbox,
        path.join(OUTPUT_SINGBOX_DIR, this.type, this.id + '.json')
      )
    ]);
  }
}