"use client";

import { useState, useEffect, useRef } from "react";
import { Button } from "@/components/ui/button";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { Input } from "@/components/ui/input";
import useStore from "@/lib/store";
import modelAdapter from "@/lib/services/adapter-instance";
import { Save, Key, Server, Eye, EyeOff, CheckCircle, XCircle, Loader2, RefreshCw } from "lucide-react";
import { translations } from "@/lib/i18n/translations";

export default function SettingsPanel() {
  const {
    language,
    apiKeys,
    setApiKey,
    selectedProvider,
    setSelectedProvider,
    qwenTokens,
    setQwenTokens,
    apiValidationStatus,
    setApiValidationStatus,
  } = useStore();
  const t = translations[language].settings;
  const common = translations[language].common;

  const [showApiKey, setShowApiKey] = useState<Record<string, boolean>>({});
  const [isAuthLoading, setIsAuthLoading] = useState(false);
  const [validating, setValidating] = useState<Record<string, boolean>>({});
  const validationDebounceRef = useRef<Record<string, NodeJS.Timeout>>({});

  const handleSave = () => {
    if (typeof window !== "undefined") {
      localStorage.setItem("promptarch-api-keys", JSON.stringify(apiKeys));
      alert(t.keysSaved);
    }
  };

  const handleLoad = () => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("promptarch-api-keys");
      if (saved) {
        try {
          const keys = JSON.parse(saved);
          if (keys.qwen) {
            setApiKey("qwen", keys.qwen);
            modelAdapter.updateQwenApiKey(keys.qwen);
          }
          if (keys.ollama) {
            setApiKey("ollama", keys.ollama);
            modelAdapter.updateOllamaApiKey(keys.ollama);
          }
          if (keys.zai) {
            setApiKey("zai", keys.zai);
            modelAdapter.updateZaiApiKey(keys.zai);
          }
        } catch (e) {
          console.error("Failed to load API keys:", e);
        }
      }
      const storedTokens = modelAdapter.getQwenTokenInfo();
      if (storedTokens) {
        setQwenTokens(storedTokens);
      }

      // Load validation status
      const storedValidation = localStorage.getItem("promptarch-api-validation");
      if (storedValidation) {
        try {
          const validation = JSON.parse(storedValidation);
          // Only use cached validation if it's less than 5 minutes old
          const now = Date.now();
          const fiveMinutes = 5 * 60 * 1000;
          const entries = Object.entries(validation) as Array<[string, any]>;
          for (const [provider, status] of entries) {
            if (status.lastValidated && (now - status.lastValidated) < fiveMinutes) {
              setApiValidationStatus(provider as any, status);
            }
          }
        } catch (e) {
          console.error("Failed to load validation status:", e);
        }
      }
    }
  };

  const validateApiKey = async (provider: "qwen" | "ollama" | "zai") => {
    const key = apiKeys[provider];
    if (!key || key.trim().length === 0) {
      setApiValidationStatus(provider, { valid: false, error: "API key is required" });
      return;
    }

    setValidating((prev) => ({ ...prev, [provider]: true }));

    try {
      const result = await modelAdapter.validateConnection(provider);

      if (result.success && result.data?.valid) {
        const status = {
          valid: true,
          lastValidated: Date.now(),
          models: result.data.models,
        };
        setApiValidationStatus(provider, status);

        // Save to localStorage
        if (typeof window !== "undefined") {
          const storedValidation = localStorage.getItem("promptarch-api-validation");
          const allValidation = storedValidation ? JSON.parse(storedValidation) : {};
          allValidation[provider] = status;
          localStorage.setItem("promptarch-api-validation", JSON.stringify(allValidation));
        }
      } else {
        const status = {
          valid: false,
          error: result.error || "Connection failed",
          lastValidated: Date.now(),
        };
        setApiValidationStatus(provider, status);
      }
    } catch (error) {
      setApiValidationStatus(provider, {
        valid: false,
        error: error instanceof Error ? error.message : "Validation failed",
        lastValidated: Date.now(),
      });
    } finally {
      setValidating((prev) => ({ ...prev, [provider]: false }));
    }
  };

  const handleApiKeyChange = (provider: string, value: string) => {
    setApiKey(provider as "qwen" | "ollama" | "zai", value);

    // Clear existing timeout
    if (validationDebounceRef.current[provider]) {
      clearTimeout(validationDebounceRef.current[provider]);
    }

    // Update the service immediately
    switch (provider) {
      case "qwen":
        modelAdapter.updateQwenApiKey(value);
        break;
      case "ollama":
        modelAdapter.updateOllamaApiKey(value);
        break;
      case "zai":
        modelAdapter.updateZaiApiKey(value);
        break;
    }

    // Debounce validation (500ms)
    if (value.trim().length > 0) {
      validationDebounceRef.current[provider] = setTimeout(() => {
        validateApiKey(provider as "qwen" | "ollama" | "zai");
      }, 500);
    } else {
      setApiValidationStatus(provider as any, { valid: false });
    }
  };

  const handleQwenAuth = async () => {
    if (qwenTokens) {
      setQwenTokens(null);
      modelAdapter.updateQwenTokens();
      modelAdapter.updateQwenApiKey(apiKeys.qwen || "");
      setApiValidationStatus("qwen", { valid: false });
      return;
    }

    setIsAuthLoading(true);
    try {
      const token = await modelAdapter.startQwenOAuth();
      setQwenTokens(token);
      modelAdapter.updateQwenTokens(token);
      // Validate after OAuth
      await validateApiKey("qwen");
    } catch (error) {
      console.error("Qwen OAuth failed", error);
      window.alert(
        error instanceof Error ? error.message : t.qwenAuthFailed
      );
    } finally {
      setIsAuthLoading(false);
    }
  };

  const getStatusIndicator = (provider: "qwen" | "ollama" | "zai") => {
    const status = apiValidationStatus[provider];

    if (validating[provider]) {
      return (
        <div className="flex items-center gap-1.5 text-blue-500">
          <Loader2 className="h-3.5 w-3.5 animate-spin" />
          <span className="text-[9px] font-medium">Validating...</span>
        </div>
      );
    }

    if (status?.valid) {
      const timeAgo = status.lastValidated
        ? `Validated ${Math.round((Date.now() - status.lastValidated) / 60000)}m ago`
        : "Connected";
      return (
        <div className="flex items-center gap-1.5 text-green-600 dark:text-green-400">
          <CheckCircle className="h-3.5 w-3.5" />
          <span className="text-[9px] font-medium">{timeAgo}</span>
        </div>
      );
    }

    if (status?.error && apiKeys[provider]?.trim().length > 0) {
      return (
        <div className="flex items-center gap-1.5 text-red-500">
          <XCircle className="h-3.5 w-3.5" />
          <span className="text-[9px] font-medium truncate max-w-[150px]" title={status.error}>
            {status.error}
          </span>
        </div>
      );
    }

    return null;
  };

  useEffect(() => {
    handleLoad();
    return () => {
      // Clear all debounce timeouts on unmount
      Object.values(validationDebounceRef.current).forEach(timeout => {
        if (timeout) clearTimeout(timeout);
      });
    };
  }, []);

  return (
    <div className="mx-auto max-w-3xl space-y-4 lg:space-y-6">
      <Card>
        <CardHeader className="p-4 lg:p-6 text-start">
          <CardTitle className="flex items-center gap-2 text-base lg:text-lg">
            <Key className="h-4 w-4 lg:h-5 lg:w-5" />
            {t.apiKeys}
          </CardTitle>
          <CardDescription className="text-xs lg:text-sm">
            {t.apiKeysDesc}
          </CardDescription>
        </CardHeader>
        <CardContent className="space-y-4 lg:space-y-6 p-4 lg:p-6 pt-0 lg:pt-0">
          <div className="space-y-2 text-start">
            <label className="flex items-center gap-2 text-xs lg:text-sm font-medium">
              <Server className="h-3.5 w-3.5 lg:h-4 lg:w-4" />
              Qwen Code API Key
            </label>
            <div className="relative">
              <Input
                type={showApiKey.qwen ? "text" : "password"}
                placeholder={t.enterKey("Qwen")}
                value={apiKeys.qwen || ""}
                onChange={(e) => handleApiKeyChange("qwen", e.target.value)}
                className="font-mono text-xs lg:text-sm pr-24"
              />
              <div className="absolute right-1 top-1/2 -translate-y-1/2 flex items-center gap-1">
                {getStatusIndicator("qwen")}
                <Button
                  type="button"
                  variant="ghost"
                  size="icon"
                  className="h-7 w-7"
                  onClick={() => setShowApiKey((prev) => ({ ...prev, qwen: !prev.qwen }))}
                >
                  {showApiKey.qwen ? (
                    <EyeOff className="h-3 w-3" />
                  ) : (
                    <Eye className="h-3 w-3" />
                  )}
                </Button>
              </div>
            </div>
            <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-2 lg:gap-4">
              <div className="flex-1 flex flex-col sm:flex-row sm:items-center gap-2">
                <p className="text-[10px] lg:text-xs text-muted-foreground">
                  {t.getApiKey}{" "}
                  <a
                    href="https://help.aliyun.com/zh/dashscope/"
                    target="_blank"
                    rel="noopener noreferrer"
                    className="text-primary hover:underline"
                  >
                    Alibaba DashScope
                  </a>
                </p>
                {apiKeys.qwen && (
                  <Button
                    variant="ghost"
                    size="sm"
                    className="h-6 px-2 text-[9px] lg:text-[10px] w-fit"
                    onClick={() => validateApiKey("qwen")}
                    disabled={validating.qwen}
                  >
                    <RefreshCw className={`h-2.5 w-2.5 mr-1 ${validating.qwen ? "animate-spin" : ""}`} />
                    Test
                  </Button>
                )}
              </div>
              <Button
                variant={qwenTokens ? "secondary" : "outline"}
                size="sm"
                className="h-7 lg:h-8 text-[10px] lg:text-xs w-full sm:w-auto"
                onClick={handleQwenAuth}
                disabled={isAuthLoading}
              >
                {isAuthLoading
                  ? t.signingIn
                  : qwenTokens
                    ? t.logoutQwen
                    : t.loginQwen}
              </Button>
            </div>
            {qwenTokens && (
              <p className="text-[9px] lg:text-[10px] text-green-600 dark:text-green-400 font-medium">
                ✓ {t.authenticated} ({t.expires}: {new Date(qwenTokens.expiresAt || 0).toLocaleString()})
              </p>
            )}
          </div>

          <div className="space-y-2 text-start">
            <label className="flex items-center gap-2 text-xs lg:text-sm font-medium">
              <Server className="h-3.5 w-3.5 lg:h-4 lg:w-4" />
              Ollama Cloud API Key
            </label>
            <div className="relative">
              <Input
                type={showApiKey.ollama ? "text" : "password"}
                placeholder={t.enterKey("Ollama")}
                value={apiKeys.ollama || ""}
                onChange={(e) => handleApiKeyChange("ollama", e.target.value)}
                className="font-mono text-xs lg:text-sm pr-24"
              />
              <div className="absolute right-1 top-1/2 -translate-y-1/2 flex items-center gap-1">
                {getStatusIndicator("ollama")}
                <Button
                  type="button"
                  variant="ghost"
                  size="icon"
                  className="h-7 w-7"
                  onClick={() => setShowApiKey((prev) => ({ ...prev, ollama: !prev.ollama }))}
                >
                  {showApiKey.ollama ? (
                    <EyeOff className="h-3 w-3" />
                  ) : (
                    <Eye className="h-3 w-3" />
                  )}
                </Button>
              </div>
            </div>
            <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-2">
              <p className="text-[10px] lg:text-xs text-muted-foreground">
                {t.getApiKey}{" "}
                <a
                  href="https://ollama.com/cloud"
                  target="_blank"
                  rel="noopener noreferrer"
                  className="text-primary hover:underline"
                >
                  ollama.com/cloud
                </a>
              </p>
              {apiKeys.ollama && (
                <Button
                  variant="ghost"
                  size="sm"
                  className="h-6 px-2 text-[9px] lg:text-[10px] w-fit"
                  onClick={() => validateApiKey("ollama")}
                  disabled={validating.ollama}
                >
                  <RefreshCw className={`h-2.5 w-2.5 mr-1 ${validating.ollama ? "animate-spin" : ""}`} />
                  Test
                </Button>
              )}
            </div>
          </div>

          <div className="space-y-2 text-start">
            <label className="flex items-center gap-2 text-xs lg:text-sm font-medium">
              <Server className="h-3.5 w-3.5 lg:h-4 lg:w-4" />
              Z.AI Plan API Key
            </label>
            <div className="relative">
              <Input
                type={showApiKey.zai ? "text" : "password"}
                placeholder={t.enterKey("Z.AI")}
                value={apiKeys.zai || ""}
                onChange={(e) => handleApiKeyChange("zai", e.target.value)}
                className="font-mono text-xs lg:text-sm pr-24"
              />
              <div className="absolute right-1 top-1/2 -translate-y-1/2 flex items-center gap-1">
                {getStatusIndicator("zai")}
                <Button
                  type="button"
                  variant="ghost"
                  size="icon"
                  className="h-7 w-7"
                  onClick={() => setShowApiKey((prev) => ({ ...prev, zai: !prev.zai }))}
                >
                  {showApiKey.zai ? (
                    <EyeOff className="h-3 w-3" />
                  ) : (
                    <Eye className="h-3 w-3" />
                  )}
                </Button>
              </div>
            </div>
            <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-2">
              <p className="text-[10px] lg:text-xs text-muted-foreground">
                {t.getApiKey}{" "}
                <a
                  href="https://docs.z.ai"
                  target="_blank"
                  rel="noopener noreferrer"
                  className="text-primary hover:underline"
                >
                  docs.z.ai
                </a>
              </p>
              {apiKeys.zai && (
                <Button
                  variant="ghost"
                  size="sm"
                  className="h-6 px-2 text-[9px] lg:text-[10px] w-fit"
                  onClick={() => validateApiKey("zai")}
                  disabled={validating.zai}
                >
                  <RefreshCw className={`h-2.5 w-2.5 mr-1 ${validating.zai ? "animate-spin" : ""}`} />
                  Test
                </Button>
              )}
            </div>
          </div>

          <Button onClick={handleSave} className="w-full h-9 lg:h-10 text-xs lg:text-sm">
            <Save className="mr-1.5 lg:mr-2 h-3.5 w-3.5 lg:h-4 lg:w-4" />
            {t.saveKeys}
          </Button>
        </CardContent>
      </Card>

      <Card>
        <CardHeader className="p-4 lg:p-6 text-start">
          <CardTitle className="text-base lg:text-lg">{t.defaultProvider}</CardTitle>
          <CardDescription className="text-xs lg:text-sm">
            {t.defaultProviderDesc}
          </CardDescription>
        </CardHeader>
        <CardContent className="space-y-3 lg:space-y-4 p-4 lg:p-6 pt-0 lg:pt-0">
          <div className="grid gap-2 lg:gap-3">
            {(["qwen", "ollama", "zai"] as const).map((provider) => (
              <button
                key={provider}
                onClick={() => setSelectedProvider(provider)}
                className={`flex items-center gap-2 lg:gap-3 rounded-lg border p-3 lg:p-4 text-left transition-colors hover:bg-muted/50 ${selectedProvider === provider
                  ? "border-primary bg-primary/5"
                  : "border-border"
                  }`}
              >
                <div className="flex h-8 w-8 lg:h-10 lg:w-10 items-center justify-center rounded-md bg-primary/10">
                  <Server className="h-4 w-4 lg:h-5 lg:w-5 text-primary" />
                </div>
                <div className="flex-1 min-w-0">
                  <h3 className="font-medium capitalize text-sm lg:text-base">{provider}</h3>
                  <p className="text-[10px] lg:text-sm text-muted-foreground truncate">
                    {provider === "qwen" && t.qwenDesc}
                    {provider === "ollama" && t.ollamaDesc}
                    {provider === "zai" && t.zaiDesc}
                  </p>
                </div>
                {selectedProvider === provider && (
                  <div className="h-2 w-2 rounded-full bg-primary flex-shrink-0" />
                )}
              </button>
            ))}
          </div>
        </CardContent>
      </Card>

      <Card>
        <CardHeader className="p-4 lg:p-6 text-start">
          <CardTitle className="text-base lg:text-lg">{t.dataPrivacy}</CardTitle>
          <CardDescription className="text-xs lg:text-sm">
            {t.dataPrivacyTitleDesc}
          </CardDescription>
        </CardHeader>
        <CardContent className="p-4 lg:p-6 pt-0 lg:pt-0">
          <div className="rounded-md border bg-muted/30 p-3 lg:p-4 text-start">
            <p className="text-xs lg:text-sm">
              {t.dataPrivacyDesc}
            </p>
          </div>
        </CardContent>
      </Card>
    </div>
  );
}