import React, { useState, useEffect } from "react";
import { motion, AnimatePresence } from "framer-motion";
import {
  Key,
  Plus,
  Trash2,
  Copy,
  Check,
  Eye,
  EyeOff,
  Code,
  FileText,
  AlertCircle,
  Clock,
  Sparkles,
  ExternalLink,
} from "lucide-react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Badge } from "@/components/ui/badge";
import { cn } from "@/lib/utils";
import { createAPIKey, listAPIKeys, deleteAPIKey } from "@/services/api";

const API_BASE_URL = import.meta.env.VITE_API_BASE_URL || "https://seth0330-ezofisocr.hf.space";

export default function APIKeys() {
  const [apiKeys, setApiKeys] = useState([]);
  const [isLoading, setIsLoading] = useState(true);
  const [error, setError] = useState(null);
  const [showCreateModal, setShowCreateModal] = useState(false);
  const [newKeyName, setNewKeyName] = useState("");
  const [isCreating, setIsCreating] = useState(false);
  const [newlyCreatedKey, setNewlyCreatedKey] = useState(null);
  const [copiedKeyId, setCopiedKeyId] = useState(null);
  const [visibleKeys, setVisibleKeys] = useState(new Set());

  // Fetch API keys on mount
  useEffect(() => {
    fetchAPIKeys();
  }, []);

  const fetchAPIKeys = async () => {
    setIsLoading(true);
    setError(null);
    try {
      const response = await listAPIKeys();
      setApiKeys(response.api_keys || []);
    } catch (err) {
      setError(err.message || "Failed to load API keys");
    } finally {
      setIsLoading(false);
    }
  };

  const handleCreateKey = async () => {
    if (!newKeyName.trim()) {
      setError("Please enter a name for your API key");
      return;
    }

    setIsCreating(true);
    setError(null);
    try {
      const response = await createAPIKey(newKeyName.trim());
      setNewlyCreatedKey(response.api_key);
      setNewKeyName("");
      setShowCreateModal(false);
      await fetchAPIKeys();
    } catch (err) {
      setError(err.message || "Failed to create API key");
    } finally {
      setIsCreating(false);
    }
  };

  const handleDeleteKey = async (keyId) => {
    if (!confirm("Are you sure you want to deactivate this API key? This action cannot be undone.")) {
      return;
    }

    try {
      await deleteAPIKey(keyId);
      await fetchAPIKeys();
    } catch (err) {
      setError(err.message || "Failed to delete API key");
    }
  };

  const copyToClipboard = (text, keyId = null) => {
    navigator.clipboard.writeText(text);
    if (keyId) {
      setCopiedKeyId(keyId);
      setTimeout(() => setCopiedKeyId(null), 2000);
    }
  };

  const toggleKeyVisibility = (keyId) => {
    const newVisible = new Set(visibleKeys);
    if (newVisible.has(keyId)) {
      newVisible.delete(keyId);
    } else {
      newVisible.add(keyId);
    }
    setVisibleKeys(newVisible);
  };

  const formatDate = (dateString) => {
    if (!dateString) return "Never";
    const date = new Date(dateString);
    return date.toLocaleDateString("en-US", {
      year: "numeric",
      month: "short",
      day: "numeric",
      hour: "2-digit",
      minute: "2-digit",
    });
  };

  return (
    <div className="min-h-screen bg-[#FAFAFA]">
      {/* Header */}
      <header className="bg-white border-b border-slate-200/80 sticky top-0 z-40 h-16">
        <div className="px-8 h-full flex items-center justify-between">
          <div>
            <h1 className="text-xl font-bold text-slate-900 tracking-tight leading-tight">
              API Keys
            </h1>
            <p className="text-sm text-slate-500 leading-tight">
              Manage API keys for external application access
            </p>
          </div>
          <Button
            onClick={() => setShowCreateModal(true)}
            className="h-10 px-6 rounded-xl font-semibold bg-gradient-to-r from-indigo-600 to-violet-600 hover:from-indigo-700 hover:to-violet-700 shadow-lg shadow-indigo-500/25 hover:shadow-xl hover:shadow-indigo-500/30 transition-all duration-300"
          >
            <Plus className="h-4 w-4 mr-2" />
            Create API Key
          </Button>
        </div>
      </header>

      {/* Main Content */}
      <div className="p-8">
        {/* Error Message */}
        {error && (
          <motion.div
            initial={{ opacity: 0, y: -10 }}
            animate={{ opacity: 1, y: 0 }}
            className="max-w-4xl mx-auto mb-6"
          >
            <div className="bg-red-50 border border-red-200 rounded-2xl p-4 flex items-start gap-3">
              <AlertCircle className="h-5 w-5 text-red-600 flex-shrink-0 mt-0.5" />
              <div className="flex-1">
                <h3 className="font-semibold text-red-900 mb-1">Error</h3>
                <p className="text-sm text-red-700">{error}</p>
              </div>
              <button
                onClick={() => setError(null)}
                className="text-red-400 hover:text-red-600 transition-colors"
              >
                ×
              </button>
            </div>
          </motion.div>
        )}

        {/* Success Message for New Key */}
        {newlyCreatedKey && (
          <motion.div
            initial={{ opacity: 0, y: -10 }}
            animate={{ opacity: 1, y: 0 }}
            className="max-w-4xl mx-auto mb-6"
          >
            <div className="bg-emerald-50 border border-emerald-200 rounded-2xl p-6">
              <div className="flex items-start gap-3 mb-4">
                <div className="h-10 w-10 rounded-xl bg-emerald-100 flex items-center justify-center flex-shrink-0">
                  <Check className="h-5 w-5 text-emerald-600" />
                </div>
                <div className="flex-1">
                  <h3 className="font-semibold text-emerald-900 mb-1">
                    API Key Created Successfully!
                  </h3>
                  <p className="text-sm text-emerald-700 mb-4">
                    ⚠️ Store this key securely - it will not be shown again.
                  </p>
                  <div className="bg-white rounded-xl p-4 border border-emerald-200">
                    <div className="flex items-center gap-2 mb-2">
                      <Key className="h-4 w-4 text-slate-500" />
                      <span className="text-xs font-medium text-slate-500 uppercase tracking-wide">
                        Your API Key
                      </span>
                    </div>
                    <div className="flex items-center gap-2">
                      <code className="flex-1 font-mono text-sm text-slate-900 break-all">
                        {newlyCreatedKey}
                      </code>
                      <Button
                        size="sm"
                        variant="outline"
                        onClick={() => copyToClipboard(newlyCreatedKey, "new")}
                        className="flex-shrink-0"
                      >
                        {copiedKeyId === "new" ? (
                          <Check className="h-4 w-4 text-emerald-600" />
                        ) : (
                          <Copy className="h-4 w-4" />
                        )}
                      </Button>
                    </div>
                  </div>
                </div>
              </div>
              <Button
                onClick={() => setNewlyCreatedKey(null)}
                className="w-full bg-emerald-600 hover:bg-emerald-700 text-white"
              >
                I've Saved My Key
              </Button>
            </div>
          </motion.div>
        )}

        {/* API Keys List */}
        <div className="max-w-4xl mx-auto">
          {isLoading ? (
            <div className="bg-white rounded-2xl border border-slate-200 p-12 text-center">
              <div className="h-12 w-12 mx-auto rounded-2xl bg-indigo-100 flex items-center justify-center mb-4 animate-pulse">
                <Key className="h-6 w-6 text-indigo-600" />
              </div>
              <p className="text-slate-600">Loading API keys...</p>
            </div>
          ) : apiKeys.length === 0 ? (
            <motion.div
              initial={{ opacity: 0, y: 20 }}
              animate={{ opacity: 1, y: 0 }}
              className="bg-white rounded-2xl border border-slate-200 p-12 text-center"
            >
              <div className="h-16 w-16 mx-auto rounded-2xl bg-slate-100 flex items-center justify-center mb-4">
                <Key className="h-8 w-8 text-slate-400" />
              </div>
              <h3 className="text-lg font-semibold text-slate-900 mb-2">
                No API Keys Yet
              </h3>
              <p className="text-slate-500 mb-6">
                Create your first API key to start using the API from external applications
              </p>
              <Button
                onClick={() => setShowCreateModal(true)}
                className="h-11 px-6 rounded-xl font-semibold bg-gradient-to-r from-indigo-600 to-violet-600 hover:from-indigo-700 hover:to-violet-700"
              >
                <Plus className="h-4 w-4 mr-2" />
                Create Your First API Key
              </Button>
            </motion.div>
          ) : (
            <div className="space-y-4">
              {apiKeys.map((key) => (
                <motion.div
                  key={key.id}
                  initial={{ opacity: 0, y: 20 }}
                  animate={{ opacity: 1, y: 0 }}
                  className="bg-white rounded-2xl border border-slate-200 p-6 hover:shadow-lg transition-shadow"
                >
                  <div className="flex items-start justify-between mb-4">
                    <div className="flex-1">
                      <div className="flex items-center gap-3 mb-2">
                        <Key className="h-5 w-5 text-indigo-600" />
                        <h3 className="font-semibold text-slate-900">{key.name}</h3>
                        {key.is_active ? (
                          <Badge className="bg-emerald-50 text-emerald-700 border-emerald-200">
                            Active
                          </Badge>
                        ) : (
                          <Badge className="bg-slate-100 text-slate-600 border-slate-200">
                            Inactive
                          </Badge>
                        )}
                      </div>
                      <div className="ml-8 space-y-2">
                        <div className="flex items-center gap-2">
                          <span className="font-mono text-sm text-slate-500 break-all">
                            {key.key_prefix}
                          </span>
                        </div>
                        <div className="flex items-center gap-4 text-xs text-slate-400">
                          <div className="flex items-center gap-1">
                            <Clock className="h-3 w-3" />
                            <span>Created: {formatDate(key.created_at)}</span>
                          </div>
                          {key.last_used_at && (
                            <div className="flex items-center gap-1">
                              <Sparkles className="h-3 w-3" />
                              <span>Last used: {formatDate(key.last_used_at)}</span>
                            </div>
                          )}
                        </div>
                      </div>
                    </div>
                    <Button
                      size="sm"
                      variant="ghost"
                      onClick={() => handleDeleteKey(key.id)}
                      className="text-red-600 hover:text-red-700 hover:bg-red-50"
                      disabled={!key.is_active}
                    >
                      <Trash2 className="h-4 w-4" />
                    </Button>
                  </div>
                </motion.div>
              ))}
            </div>
          )}
        </div>

        {/* API Usage Guide */}
        <motion.div
          initial={{ opacity: 0, y: 20 }}
          animate={{ opacity: 1, y: 0 }}
          transition={{ delay: 0.2 }}
          className="max-w-4xl mx-auto mt-12"
        >
          <div className="bg-white rounded-2xl border border-slate-200 p-8">
            <div className="flex items-center gap-3 mb-6">
              <div className="h-12 w-12 rounded-xl bg-indigo-50 flex items-center justify-center">
                <Code className="h-6 w-6 text-indigo-600" />
              </div>
              <div>
                <h2 className="text-xl font-bold text-slate-900">How to Use API Keys</h2>
                <p className="text-sm text-slate-500">
                  Integrate document parsing into your external applications
                </p>
              </div>
            </div>

            <div className="space-y-6">
              {/* Python Example */}
              <div className="bg-slate-50 rounded-xl p-6 border border-slate-200">
                <div className="flex items-center gap-2 mb-4">
                  <FileText className="h-5 w-5 text-slate-600" />
                  <h3 className="font-semibold text-slate-900">Python Example</h3>
                </div>
                <pre className="bg-slate-900 text-slate-100 rounded-lg p-4 overflow-x-auto text-sm">
                  <code>{`import requests

API_URL = "${API_BASE_URL}"
API_KEY = "sk_live_YOUR_API_KEY_HERE"

def extract_document(file_path, key_fields=None):
    with open(file_path, 'rb') as f:
        files = {'file': f}
        data = {}
        if key_fields:
            data['key_fields'] = key_fields
        
        response = requests.post(
            f"{API_URL}/api/extract",
            headers={"X-API-Key": API_KEY},
            files=files,
            data=data
        )
        return response.json()

# Usage
result = extract_document("invoice.pdf", 
    key_fields="Invoice Number,Invoice Date")
print(result)`}</code>
                </pre>
                <Button
                  size="sm"
                  variant="outline"
                  onClick={() => copyToClipboard(`import requests

API_URL = "${API_BASE_URL}"
API_KEY = "sk_live_YOUR_API_KEY_HERE"

def extract_document(file_path, key_fields=None):
    with open(file_path, 'rb') as f:
        files = {'file': f}
        data = {}
        if key_fields:
            data['key_fields'] = key_fields
        
        response = requests.post(
            f"{API_URL}/api/extract",
            headers={"X-API-Key": API_KEY},
            files=files,
            data=data
        )
        return response.json()

# Usage
result = extract_document("invoice.pdf", 
    key_fields="Invoice Number,Invoice Date")
print(result)`)}
                  className="mt-3"
                >
                  <Copy className="h-3 w-3 mr-2" />
                  Copy Code
                </Button>
              </div>

              {/* cURL Example */}
              <div className="bg-slate-50 rounded-xl p-6 border border-slate-200">
                <div className="flex items-center gap-2 mb-4">
                  <FileText className="h-5 w-5 text-slate-600" />
                  <h3 className="font-semibold text-slate-900">cURL Example</h3>
                </div>
                <pre className="bg-slate-900 text-slate-100 rounded-lg p-4 overflow-x-auto text-sm">
                  <code>{`curl -X POST ${API_BASE_URL}/api/extract \\
  -H "X-API-Key: sk_live_YOUR_API_KEY_HERE" \\
  -F "file=@document.pdf" \\
  -F "key_fields=Invoice Number,Invoice Date,Total Amount"`}</code>
                </pre>
                <Button
                  size="sm"
                  variant="outline"
                  onClick={() => copyToClipboard(`curl -X POST ${API_BASE_URL}/api/extract \\
  -H "X-API-Key: sk_live_YOUR_API_KEY_HERE" \\
  -F "file=@document.pdf" \\
  -F "key_fields=Invoice Number,Invoice Date,Total Amount"`)}
                  className="mt-3"
                >
                  <Copy className="h-3 w-3 mr-2" />
                  Copy Code
                </Button>
              </div>

              {/* JavaScript Example */}
              <div className="bg-slate-50 rounded-xl p-6 border border-slate-200">
                <div className="flex items-center gap-2 mb-4">
                  <FileText className="h-5 w-5 text-slate-600" />
                  <h3 className="font-semibold text-slate-900">JavaScript/Node.js Example</h3>
                </div>
                <pre className="bg-slate-900 text-slate-100 rounded-lg p-4 overflow-x-auto text-sm">
                  <code>{`const FormData = require('form-data');
const fs = require('fs');
const axios = require('axios');

const API_URL = '${API_BASE_URL}';
const API_KEY = 'sk_live_YOUR_API_KEY_HERE';

async function extractDocument(filePath, keyFields = null) {
  const form = new FormData();
  form.append('file', fs.createReadStream(filePath));
  if (keyFields) {
    form.append('key_fields', keyFields);
  }

  const response = await axios.post(
    \`\${API_URL}/api/extract\`,
    form,
    {
      headers: {
        'X-API-Key': API_KEY,
        ...form.getHeaders()
      }
    }
  );
  return response.data;
}

// Usage
extractDocument('invoice.pdf', 'Invoice Number,Invoice Date')
  .then(result => console.log(result));`}</code>
                </pre>
                <Button
                  size="sm"
                  variant="outline"
                  onClick={() => copyToClipboard(`const FormData = require('form-data');
const fs = require('fs');
const axios = require('axios');

const API_URL = '${API_BASE_URL}';
const API_KEY = 'sk_live_YOUR_API_KEY_HERE';

async function extractDocument(filePath, keyFields = null) {
  const form = new FormData();
  form.append('file', fs.createReadStream(filePath));
  if (keyFields) {
    form.append('key_fields', keyFields);
  }

  const response = await axios.post(
    \`\${API_URL}/api/extract\`,
    form,
    {
      headers: {
        'X-API-Key': API_KEY,
        ...form.getHeaders()
      }
    }
  );
  return response.data;
}

// Usage
extractDocument('invoice.pdf', 'Invoice Number,Invoice Date')
  .then(result => console.log(result));`)}
                  className="mt-3"
                >
                  <Copy className="h-3 w-3 mr-2" />
                  Copy Code
                </Button>
              </div>
            </div>

            <div className="mt-6 p-4 bg-indigo-50 rounded-xl border border-indigo-200">
              <div className="flex items-start gap-3">
                <AlertCircle className="h-5 w-5 text-indigo-600 flex-shrink-0 mt-0.5" />
                <div className="flex-1">
                  <h4 className="font-semibold text-indigo-900 mb-1">API Endpoint</h4>
                  <p className="text-sm text-indigo-700 mb-2">
                    <code className="bg-white px-2 py-1 rounded text-indigo-900">
                      POST {API_BASE_URL}/api/extract
                    </code>
                  </p>
                  <p className="text-xs text-indigo-600">
                    • Max file size: 4 MB • Supported formats: PDF, PNG, JPEG, TIFF
                  </p>
                </div>
              </div>
            </div>
          </div>
        </motion.div>
      </div>

      {/* Create API Key Modal */}
      <AnimatePresence>
        {showCreateModal && (
          <motion.div
            initial={{ opacity: 0 }}
            animate={{ opacity: 1 }}
            exit={{ opacity: 0 }}
            className="fixed inset-0 bg-black/50 z-50 flex items-center justify-center p-4"
            onClick={() => !isCreating && setShowCreateModal(false)}
          >
            <motion.div
              initial={{ scale: 0.95, opacity: 0 }}
              animate={{ scale: 1, opacity: 1 }}
              exit={{ scale: 0.95, opacity: 0 }}
              onClick={(e) => e.stopPropagation()}
              className="bg-white rounded-2xl p-6 max-w-md w-full shadow-2xl"
            >
              <h2 className="text-xl font-bold text-slate-900 mb-2">Create New API Key</h2>
              <p className="text-sm text-slate-500 mb-6">
                Give your API key a descriptive name to identify it later
              </p>
              <Input
                placeholder="e.g., Production API, Test Environment"
                value={newKeyName}
                onChange={(e) => setNewKeyName(e.target.value)}
                className="mb-6"
                onKeyPress={(e) => e.key === "Enter" && handleCreateKey()}
              />
              <div className="flex gap-3">
                <Button
                  variant="outline"
                  onClick={() => {
                    setShowCreateModal(false);
                    setNewKeyName("");
                  }}
                  disabled={isCreating}
                  className="flex-1"
                >
                  Cancel
                </Button>
                <Button
                  onClick={handleCreateKey}
                  disabled={isCreating || !newKeyName.trim()}
                  className="flex-1 bg-gradient-to-r from-indigo-600 to-violet-600 hover:from-indigo-700 hover:to-violet-700"
                >
                  {isCreating ? "Creating..." : "Create Key"}
                </Button>
              </div>
            </motion.div>
          </motion.div>
        )}
      </AnimatePresence>
    </div>
  );
}