'use client';

import { useState, useEffect } from 'react';
import { useParams } from 'next/navigation';
import { TemplateEditor } from '@/components/numbering/template-editor';
import { SequenceViewer } from '@/components/numbering/sequence-viewer';
import { numberingApi } from '@/lib/api/numbering';
import { NumberingTemplate } from '@/lib/api/numbering';
import { useRouter } from 'next/navigation';
import { Loader2 } from 'lucide-react';
import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
import { useCorrespondenceTypes, useContracts, useDisciplines } from '@/hooks/use-master-data';
import { useProjects } from '@/hooks/use-projects';
import { toast } from 'sonner';

export default function EditTemplatePage() {
  const params = useParams();
  const id = params['id'] as string;
  const router = useRouter();
  const [loading, setLoading] = useState(true);
  const [template, setTemplate] = useState<NumberingTemplate | null>(null);

  // Master Data
  const { data: correspondenceTypes = [] } = useCorrespondenceTypes();
  const { data: projects = [] } = useProjects();
  const projectId = template?.projectId || 1;
  const { data: contracts = [] } = useContracts(projectId);
  const contractId = contracts[0]?.id;
  const { data: disciplines = [] } = useDisciplines(contractId);

  const selectedProjectName =
    projects.find((p: { id: number; projectName: string }) => p.id === projectId)?.projectName ||
    'LCBP3';

  useEffect(() => {
    const fetchTemplate = async () => {
      setLoading(true);
      try {
        const data = await numberingApi.getTemplate(parseInt(id));
        if (data) {
          setTemplate(data);
        }
      } catch (error) {
        toast.error('Failed to load template');
        console.error('[EditTemplatePage] fetchTemplate:', error);
      } finally {
        setLoading(false);
      }
    };

    fetchTemplate();
  }, [id]);

  const handleSave = async (data: Partial<NumberingTemplate>) => {
    try {
      await numberingApi.saveTemplate({ ...data, id: parseInt(id) });
      router.push('/admin/doc-control/numbering');
    } catch (error) {
      toast.error('Failed to update template');
      console.error('[EditTemplatePage] handleSave:', error);
    }
  };

  const handleCancel = () => {
    router.push("/admin/numbering");
  };

  if (loading) {
    return (
      <div className="flex justify-center py-12">
        <Loader2 className="h-8 w-8 animate-spin text-muted-foreground" />
      </div>
    );
  }

  if (!template) {
    return (
      <div className="p-6">
        <p className="text-muted-foreground">Template not found</p>
      </div>
    );
  }

  return (
    <div className="p-6 space-y-6">
      <h1 className="text-3xl font-bold">Edit Numbering Template</h1>

      <Tabs defaultValue="config">
        <TabsList>
          <TabsTrigger value="config">Configuration</TabsTrigger>
          <TabsTrigger value="sequences">Sequences</TabsTrigger>
        </TabsList>

        <TabsContent value="config" className="mt-4">
          <TemplateEditor
            template={template}
            projectId={template.projectId || 1}
            projectName={selectedProjectName}
            correspondenceTypes={correspondenceTypes}
            disciplines={disciplines}
            onSave={handleSave}
            onCancel={handleCancel}
          />
        </TabsContent>

        <TabsContent value="sequences" className="mt-4">
          <SequenceViewer />
        </TabsContent>
      </Tabs>
    </div>
  );
}