"use server";

import type { Config, Version, CurseForgeFile } from "@/types";
import { modrinthClient, curseforgeClient } from "./clients";
import { listVersions } from "@/lib/modrinth";
import { getFiles } from "@/lib/curseforge";
import { Template } from "@/lib/utils/template";

/**
 * 获取 Modrinth 项目的全部已有版本（不含 changelog 以减小响应体）。
 */
export async function fetchModrinthVersions(
  config: Config,
): Promise<Version[]> {
  return listVersions(modrinthClient, config.modrinth.project_id, {
    include_changelog: false,
  });
}

/**
 * 获取 CurseForge 项目的全部已有文件（自动遍历所有分页）。
 */
export async function fetchCurseForgeVersions(
  config: Config,
): Promise<CurseForgeFile[]> {
  const pageSize = 50;
  let index = 0;
  const allFiles: CurseForgeFile[] = [];

  while (true) {
    const response = await getFiles(curseforgeClient, {
      modId: config.curseforge.project_id,
      index,
      pageSize,
    });
    allFiles.push(...response.data);

    if (allFiles.length >= response.pagination.totalCount) {
      break;
    }
    index += pageSize;
  }

  return allFiles;
}

/** 单个 MC 版本的比较结果 */
export interface VersionMatch {
  exists: boolean;
  existingVersion?: Version;
}

/** 单个 MC 版本的文件比较结果 */
export interface FileMatch {
  exists: boolean;
  existingFile?: CurseForgeFile;
}

/** 版本确认的完整比较结果 */
export interface VersionComparison {
  modrinth: Record<string, VersionMatch>;
  curseforge: Record<string, FileMatch>;
}

/**
 * 将待发布版本与两个平台的已有版本进行比对。
 *
 * @param config      项目配置
 * @param version     项目版本号（如 "1.0.0"）
 * @param mc_versions 待发布的 MC 版本列表
 * @returns           按 MC 版本分组的比对结果
 */
export async function compareVersions(
  config: Config,
  version: string,
  mc_versions: string[],
): Promise<VersionComparison> {
  // 并行获取两个平台的已有版本
  const [modrinthVersions, curseforgeFiles] = await Promise.all([
    fetchModrinthVersions(config),
    fetchCurseForgeVersions(config),
  ]);

  // ── Modrinth：按 version 模板生成 version_number 后匹配 ──
  const modrinth: Record<string, VersionMatch> = {};
  const modrinthTmpl = new Template(config.modrinth.version);

  for (const mc_version of mc_versions) {
    const generatedVersion = modrinthTmpl.format({ version, mc_version });
    const existing = modrinthVersions.find(
      (v) => v.version_number === generatedVersion,
    );
    modrinth[mc_version] = existing
      ? { exists: true, existingVersion: existing }
      : { exists: false };
  }

  // ── CurseForge：按 filename_format 模板生成文件名后匹配 ──
  const curseforge: Record<string, FileMatch> = {};
  const curseforgeTmpl = new Template(config.filename_format);

  for (const mc_version of mc_versions) {
    const generatedFilename = curseforgeTmpl.format({ version, mc_version });
    const existing = curseforgeFiles.find(
      (f) => f.fileName === generatedFilename,
    );
    curseforge[mc_version] = existing
      ? { exists: true, existingFile: existing }
      : { exists: false };
  }

  return { modrinth, curseforge };
}