/**
 * i18n engine for pi-mcp-market.
 *
 * Supports zh (Chinese) and en (English) out of the box.
 * Extensible — add entries to the dictionary for more languages.
 *
 * Usage:
 *   import { t, setLang } from "./i18n.ts";
 *   t("market.title")           // → "MCP Server Market" (en) or "MCP 服务器市场" (zh)
 *   setLang("zh");              // switch at runtime
 *   t("common.enter")           // → "确认"
 *
 * Dictionary sections match file/feature domains for maintainability.
 */

export type Lang = "zh" | "en";

let currentLang: Lang = "zh";

export function getLang(): Lang {
  return currentLang;
}

export function setLang(lang: Lang): void {
  currentLang = lang;
}

/** Shorthand for t(). */
export const _ = t;

/** Look up a key in the current language dictionary. Falls back to zh, then the key itself. */
export function t(key: string, fallback?: string): string {
  const dict = DICTIONARY[key];
  if (!dict) return fallback ?? key;
  return (dict as Record<string, string>)[currentLang] ?? (dict as Record<string, string>).zh ?? key;
}

/** All keys in the current language (for panel building). */
export function lang(): Lang {
  return currentLang;
}

type DictValue = string | Record<string, string>;

const DICTIONARY: Record<string, DictValue> = {
  // ── Market Panel ────────────────────────────────────────────────
  "market.title":                    { zh: "MCP 服务器市场",      en: "MCP Server Market" },
  "market.adapterMissing":           { zh: "⚠ pi-mcp-adapter 未安装", en: "⚠ pi-mcp-adapter not installed" },
  "market.searchLabel":              { zh: "搜索: ",               en: "Search: " },
  "market.searchPlaceholder":        { zh: "输入以模糊搜索…",       en: "Type to fuzzy search…" },
  "market.searchHint":               { zh: " Esc 清空 ",           en: " Esc clear " },
  "market.sourceAll":                { zh: "全部",                 en: "All" },
  "market.sourceSwitch":             { zh: "←/→ 切换",             en: "←/→ switch" },
  "market.loading":                  { zh: "正在加载 MCP 市场源…", en: "Loading MCP market sources…" },
  "market.noRegistries":             { zh: "未配置 remote registry，请编辑 registries.json", en: "No registries configured, edit registries.json" },
  "market.allFailed":                { zh: "所有源拉取失败，且无可用缓存", en: "All sources failed and no cached data" },
  "market.noServers":                { zh: "源已配置，但没有可安装的服务器", en: "Sources configured but no installable servers" },
  "market.noMatch":                  { zh: "没有匹配的服务器",     en: "No servers match" },
  "market.helpUpDown":               { zh: "↑/↓ 移动",           en: "↑/↓ navigate" },
  "market.helpEnter":                { zh: "Enter 预览/安装",     en: "Enter preview/install" },
  "market.helpSource":               { zh: "←/→ 切源",           en: "←/→ source" },
  "market.helpClose":                { zh: "Esc 关闭",            en: "Esc close" },
  "market.installed":                { zh: "● 已安装",            en: "● Installed" },
  "market.ready":                    { zh: "✅ 已就绪",           en: "✅ Ready" },
  "market.pendingConfig":            { zh: "⚠ 待配置",           en: "⚠ Needs config" },
  "market.installedTo":              { zh: "已安装到 mcp.json",   en: "Installed to mcp.json" },
  "market.installedToPending":       { zh: "已安装到 mcp.json，但有配置未完成", en: "Installed to mcp.json, config pending" },
  "market.needsEnv":                 { zh: "需设置",              en: "Needs" },
  "market.badgeInstalled":           { zh: "● 已安装",            en: "● Installed" },
  "market.badgeConfig":              { zh: "⚠ 待配置",            en: "⚠ Needs config" },
  "market.toolCount":                { zh: "🧰 {n} tools",       en: "🧰 {n} tools" },
  "market.previewBeforeInstall":     { zh: "安装前 Enter 预览配置", en: "Press Enter to preview config" },

  // ── Source filter tabs ──────────────────────────────────────────
  "market.sourceInstalled":          { zh: "已安装",              en: "Installed" },
  "market.loadingSpinner":           { zh: " ⏳",                 en: " ⏳" },
  "market.failedIcon":               { zh: " ⚠",                 en: " ⚠" },

  // ── Connection failures ────────────────────────────────────────
  "market.failedSources":            { zh: "⚠ 无法连接: {sources}（已用缓存/跳过）", en: "⚠ Unreachable: {sources} (fallback to cache)" },

  // ── Form panel ─────────────────────────────────────────────────
  "form.title":                      { zh: "填写必填项: {name}",          en: "Fill required fields: {name}" },
  "form.hint":                       { zh: "值将明文保存在 mcp.json（MCP 标准）。Esc 跳过 → 标记「待配置」。", en: "Values stored in plaintext (MCP standard). Esc to skip → marked as pending." },
  "form.inputPlaceholder":           { zh: "输入值…",                     en: "Enter value…" },
  "form.skipped":                    { zh: "(跳过)",                      en: "(skipped)" },
  "form.defaultHint":                { zh: " 必填环境变量，请在 {key} 对应服务的官网申请", en: " Required env, obtain from the service provider" },
  "form.helpNext":                   { zh: "Enter 下一步/完成",           en: "Enter next/finish" },
  "form.helpSkip":                   { zh: "Esc 跳过",                    en: "Esc skip" },
  "form.helpCancel":                 { zh: "Ctrl+C 取消",                 en: "Ctrl+C cancel" },

  // ── Preview panel ──────────────────────────────────────────────
  "preview.title":                   { zh: "安装确认",                    en: "Install Confirmation" },
  "preview.auth":                    { zh: "认证: {type}",                en: "Auth: {type}" },
  "preview.tools":                   { zh: "工具: {n} 个",               en: "Tools: {n}" },
  "preview.willWrite":               { zh: "将写入 ~/.pi/agent/mcp.json:", en: "Will write to ~/.pi/agent/mcp.json:" },
  "preview.confirmInstall":          { zh: "Enter 确认安装",              en: "Enter to install" },
  "preview.cancelInstall":           { zh: "Esc 取消",                    en: "Esc cancel" },

  "preview.hintReload":              { zh: "安装后：运行 /mcp reconnect 或 /reload 加载新服务器", en: "After install: run /mcp reconnect or /reload" },
  "preview.hintOauth":               { zh: "认证方式：OAuth — 安装后运行 /mcp-auth <服务器名> 完成授权", en: "Auth: OAuth — run /mcp-auth <name> after install" },
  "preview.hintBearer":              { zh: "需要设置环境变量 ${var}（安装后运行 /reload 生效）", en: "Set env ${var} (run /reload after install)" },
  "preview.hintWhereToGet":          { zh: "获取地址：{url}",             en: "Get from: {url}" },
  "preview.hintOnekey":              { zh: "OneKey 代理：需要设置 $DEEPNLP_ONEKEY_ROUTER_ACCESS", en: "OneKey proxy: need $DEEPNLP_ONEKEY_ROUTER_ACCESS" },
  "preview.hintOnekeyUrl":           { zh: "获取密钥：https://www.deepnlp.org/workspace/keys", en: "Get key: https://www.deepnlp.org/workspace/keys" },
  "preview.hintOnekeyCredit":        { zh: "注意：DeepNLP MCP 使用 credits 计费（有免费试用额度，Pro $9.9/月），并非全免费服务", en: "Note: DeepNLP MCP uses credits (free trial, Pro $9.9/month)" },
  "preview.hintNpx":                 { zh: "npx 服务器：如果连接失败，在终端手动运行此命令查看具体错误", en: "npx server: if connection fails, run the command manually to see the error" },
  "preview.hintUrl":                 { zh: "远程服务器：如果连接失败，检查是否需要 API Key 或正确的 endpoint URL", en: "Remote server: if connection fails, check for API Key or correct endpoint URL" },

  // ── Auth labels ────────────────────────────────────────────────
  "auth.none":                       { zh: "✅ 无需认证",                en: "✅ No auth required" },
  "auth.apiKey":                     { zh: "🔑 需要 API Key",            en: "🔑 API Key needed" },
  "auth.bearer":                     { zh: "🔑 需要 Bearer Token",       en: "🔑 Bearer Token needed" },
  "auth.oauth":                      { zh: "🔐 需要 OAuth",              en: "🔐 OAuth needed" },
  "auth.unknown":                    { zh: "❓ 认证类型未知",            en: "❓ Unknown auth type" },

  // ── Config errors ──────────────────────────────────────────────
  "config.mcpCorrupted":             { zh: "mcp.json 配置损坏，已备份到 {backup}。请检查后决定是否修复，市场不会覆盖它。", en: "mcp.json corrupted, backed up to {backup}. Check before fixing, the market won't overwrite it." },
  "config.backupFailed":             { zh: "无法备份损坏的配置文件：{msg}", en: "Cannot backup corrupted config: {msg}" },

  // ── Install / uninstall messages ───────────────────────────────
  "install.failed":                  { zh: "安装失败: {msg}",            en: "Install failed: {msg}" },
  "install.success":                 { zh: "安装成功",                    en: "Install succeeded" },
  "uninstall.failed":               { zh: "卸载失败: {msg}",            en: "Uninstall failed: {msg}" },
  "uninstall.success":              { zh: "卸载成功",                    en: "Uninstall succeeded" },

  // ── Adapter messages ───────────────────────────────────────────
  "adapter.missing":                 { zh: "未检测到 pi-mcp-adapter。市场可以照常浏览/安装（写入 mcp.json），但连接服务器需要安装它：运行 `pi install npm:pi-mcp-adapter`。", en: "pi-mcp-adapter not detected. Market can browse/install (write to mcp.json) but needs it to connect servers: run `pi install npm:pi-mcp-adapter`." },

  // ── Headless mode ──────────────────────────────────────────────
  "headless.available":              { zh: "MCP 市场: {n} 个服务器可用 ({names})。交互面板需要 TUI 模式（/mcp-market）。", en: "MCP Market: {n} servers available ({names}). Interactive panel needs TUI mode (/mcp-market)." },

  // ── Language command ───────────────────────────────────────────
  "lang.current":                    { zh: "当前语言: {lang}",            en: "Current language: {lang}" },
  "lang.switchedTo":                 { zh: "已切换到 {lang}",             en: "Switched to {lang}" },
  "lang.usage":                      { zh: "用法: /mcp-market lang [zh|en]  — 切换语言", en: "Usage: /mcp-market lang [zh|en] — switch language" },
  "lang.unknown":                    { zh: "不支持的语言: {lang}，可用: zh, en", en: "Unsupported language: {lang}, available: zh, en" },
  "lang.invalid":                    { zh: "语言代码无效。用法: /mcp-market lang zh|en", en: "Invalid lang code. Usage: /mcp-market lang zh|en" },
  "lang.displayName_zh":            { zh: "中文",                        en: "Chinese" },
  "lang.displayName_en":            { zh: "英文",                        en: "English" },
};

type Interpolate = Record<string, string | number>;

/** t() with interpolation — replaces {key} placeholders. */
export function ti(key: string, values: Interpolate, fallback?: string): string {
  let s = t(key, fallback);
  for (const [k, v] of Object.entries(values)) {
    s = s.replace(new RegExp(`\\{${k}\\}`, "g"), String(v));
  }
  return s;
}