import { useState } from 'react';
import { useNavigate, useSearchParams } from 'react-router-dom';
import { useQuery, useMutation } from '@tanstack/react-query';
import { AdminLayout } from '@/components/layout/AdminLayout';
import { IucnAssessmentForm } from '@/components/admin/IucnAssessmentForm';
import { iucnAssessmentsApi, speciesApi, IucnAssessment, Species } from '@/services/adminApi';
import { useToast } from '@/hooks/use-toast';
import { Button } from '@/components/ui/button';
import { ChevronLeft } from 'lucide-react';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import { Label } from '@/components/ui/label';

export default function CreateIucnAssessment() {
  const [isSubmitting, setIsSubmitting] = useState(false);
  const [searchParams] = useSearchParams();
  const { toast } = useToast();
  const [selectedSpeciesId, setSelectedSpeciesId] = useState<string | null>(
    searchParams.get('species_id')
  );
  const navigate = useNavigate();
  
  // Fetch all species for the dropdown
  const { data: species, isLoading: speciesLoading } = useQuery({
    queryKey: ['admin', 'species', 'all'],
    queryFn: async () => {
      const { data } = await speciesApi.getAll(1, 500); // Fetch up to 500 species
      return data;
    }
  });
  
  // If a species_id was provided in the URL params, fetch that species details
  const { data: selectedSpecies } = useQuery({
    queryKey: ['admin', 'species', selectedSpeciesId],
    queryFn: () => selectedSpeciesId ? speciesApi.getById(selectedSpeciesId) : null,
    enabled: !!selectedSpeciesId
  });
  
  // Create IUCN assessment mutation
  const createMutation = useMutation({
    mutationFn: (data: IucnAssessment) => iucnAssessmentsApi.create(data),
    onSuccess: () => {
      toast({
        title: 'Success',
        description: 'IUCN assessment has been created successfully.',
      });
      
      // Navigate back to species detail page if we came from there
      // if (selectedSpeciesId) {
      //   navigate(`/admin/species/${selectedSpeciesId}`);
      // } else {
      //   navigate('/admin/iucn-assessments');
      // }
    },
    onError: (error) => {
      toast({
        variant: 'destructive',
        title: 'Error',
        description: `Failed to create IUCN assessment: ${(error as Error).message}`,
      });
      // setIsSubmitting(false); // Will be handled by onSettled
    },
    onSettled: () => {
      setIsSubmitting(false);
    }
  });
  
  const handleSubmit = (data: IucnAssessment) => {
    setIsSubmitting(true);
    createMutation.mutate(data);
  };

  const handleSpeciesChange = (value: string) => {
    setSelectedSpeciesId(value);
  };

  return (
    <AdminLayout>
      <div className="mb-6">
        <Button 
          variant="outline" 
          className="mb-4"
          onClick={() => navigate('/admin/iucn-assessments')}
        >
          <ChevronLeft className="mr-2 h-4 w-4" />
          Back to IUCN Assessments
        </Button>
        
        <h1 className="text-3xl font-bold">Add New IUCN Assessment</h1>
        <p className="text-muted-foreground">Create a new IUCN Red List assessment</p>
      </div>
      
      {/* Species selection dropdown (only if not pre-selected) */}
      {!searchParams.get('species_id') && (
        <div className="mb-6 rounded-md border p-6">
          <Label htmlFor="species-select" className="text-lg font-medium">
            Select Species
          </Label>
          <p className="mb-4 text-sm text-muted-foreground">
            Choose the species for this IUCN assessment
          </p>
          
          <div className="max-w-md">
            <Select 
              value={selectedSpeciesId || ''} 
              onValueChange={handleSpeciesChange}
              disabled={speciesLoading}
            >
              <SelectTrigger className="w-full">
                <SelectValue placeholder="Select a species" />
              </SelectTrigger>
              <SelectContent>
                {species?.map((s: Species) => (
                  <SelectItem key={s.id} value={s.id!}>
                    <span className="italic">{s.scientific_name}</span>
                    {' - '}
                    <span>{s.common_name}</span>
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>
          </div>
        </div>
      )}
      
      {/* Only show the form if a species is selected */}
      {selectedSpeciesId ? (
        <div className="rounded-md border p-6">
          <div className="mb-4">
            <h2 className="text-xl font-semibold">
              {selectedSpecies ? (
                <>
                  IUCN Assessment for <span className="italic">{selectedSpecies.scientific_name}</span>
                </>
              ) : (
                'New IUCN Assessment'
              )}
            </h2>
          </div>
          
          <IucnAssessmentForm
            onSubmit={handleSubmit}
            isSubmitting={isSubmitting}
            speciesId={selectedSpeciesId}
          />
        </div>
      ) : (
        !searchParams.get('species_id') && (
          <div className="rounded-md border p-6 text-center">
            <p className="text-muted-foreground">Please select a species to continue</p>
          </div>
        )
      )}
    </AdminLayout>
  );
}