import { useState } from "react";
import { zodResolver } from "@hookform/resolvers/zod";
import { useForm } from "react-hook-form";
import * as z from "zod";

import { Button } from "@/components/ui/button";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { Input } from "@/components/ui/input";
import {
  Form,
  FormControl,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from "@/components/ui/form";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "@/components/ui/select";
import { 
  Competency,
  CompetencyCategory,
  CompetencyCreateRequest,
  CompetencyUpdateRequest 
} from "@/types";

// Define form schema
const formSchema = z.object({
  title: z.string().min(2, { message: "Title must be at least 2 characters." }),
  category: z.enum(["Core", "Technical", "Leadership", "Communication", "Teamwork"] as const),
  weightage: z.coerce
    .number()
    .min(1, { message: "Weightage must be at least 1." })
    .max(100, { message: "Weightage must be at most 100." }),
});

interface CompetencyDialogProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  onSubmit: (data: CompetencyCreateRequest | CompetencyUpdateRequest) => void;
  competencyToEdit?: Competency;
  isLoading?: boolean;
}

export function CompetencyDialog({
  open,
  onOpenChange,
  onSubmit,
  competencyToEdit,
  isLoading = false,
}: CompetencyDialogProps) {
  const [error, setError] = useState<string | null>(null);

  const form = useForm<z.infer<typeof formSchema>>({
    resolver: zodResolver(formSchema),
    defaultValues: {
      title: competencyToEdit?.title || "",
      category: competencyToEdit?.category || "Core",
      weightage: competencyToEdit?.weightage || 10,
    },
  });

  function handleSubmit(values: z.infer<typeof formSchema>) {
    setError(null);
    
    if (competencyToEdit) {
      onSubmit({
        competencyId: competencyToEdit.competencyId,
        title: values.title,
        category: values.category,
        weightage: values.weightage,
      });
    } else {
      onSubmit({
        title: values.title,
        category: values.category,
        weightage: values.weightage,
      });
    }
  }

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="sm:max-w-[425px]">
        <DialogHeader>
          <DialogTitle>{competencyToEdit ? "Edit Competency" : "Create Competency"}</DialogTitle>
          <DialogDescription>
            {competencyToEdit 
              ? "Edit the details of this competency." 
              : "Add a new competency to the system."
            }
          </DialogDescription>
        </DialogHeader>
        <Form {...form}>
          <form onSubmit={form.handleSubmit(handleSubmit)} className="space-y-4">
            <FormField
              control={form.control}
              name="title"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>Title</FormLabel>
                  <FormControl>
                    <Input placeholder="Problem Solving" {...field} />
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />
            <FormField
              control={form.control}
              name="category"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>Category</FormLabel>
                  <Select 
                    onValueChange={field.onChange} 
                    defaultValue={field.value}
                  >
                    <FormControl>
                      <SelectTrigger>
                        <SelectValue placeholder="Select a category" />
                      </SelectTrigger>
                    </FormControl>
                    <SelectContent>
                      <SelectItem value="Core">Core</SelectItem>
                      <SelectItem value="Technical">Technical</SelectItem>
                      <SelectItem value="Leadership">Leadership</SelectItem>
                      <SelectItem value="Communication">Communication</SelectItem>
                      <SelectItem value="Teamwork">Teamwork</SelectItem>
                    </SelectContent>
                  </Select>
                  <FormMessage />
                </FormItem>
              )}
            />
            <FormField
              control={form.control}
              name="weightage"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>Weightage (%)</FormLabel>
                  <FormControl>
                    <Input 
                      type="number" 
                      min={1} 
                      max={100} 
                      placeholder="10" 
                      {...field} 
                    />
                  </FormControl>
                  <FormMessage />
                </FormItem>
              )}
            />
            {error && <p className="text-sm font-medium text-destructive">{error}</p>}
            <DialogFooter>
              <Button 
                type="button" 
                variant="outline" 
                onClick={() => onOpenChange(false)}
                disabled={isLoading}
              >
                Cancel
              </Button>
              <Button type="submit" disabled={isLoading}>
                {isLoading ? "Saving..." : competencyToEdit ? "Update" : "Create"}
              </Button>
            </DialogFooter>
          </form>
        </Form>
      </DialogContent>
    </Dialog>
  );
}