"use client";

import { useState } from "react";
import { useRouter } from "next/navigation";
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import { z } from "zod";
import { Loader2, Save } from "lucide-react";
import { toast } from "sonner";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Textarea } from "@/components/ui/textarea";
import {
  Form,
  FormControl,
  FormDescription,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from "@/components/ui/form";
import { PermissionPicker } from "./permission-picker";

const formSchema = z.object({
  name: z.string().min(1, "Name is required").regex(/^[a-z0-9-]+$/, "Name must be lowercase with hyphens only"),
  description: z.string().optional(),
  permissions: z.record(z.string(), z.array(z.string())),
});

type FormData = z.infer<typeof formSchema>;

interface Role {
  id: string;
  name: string;
  description: string | null;
  permissions: Record<string, string[]>;
  is_system: boolean;
}

interface RoleFormProps {
  role?: Role;
}

export function RoleForm({ role }: RoleFormProps) {
  const router = useRouter();
  const [isLoading, setIsLoading] = useState(false);
  const isEditing = !!role;

  const form = useForm<FormData>({
    resolver: zodResolver(formSchema),
    defaultValues: {
      name: role?.name || "",
      description: role?.description || "",
      permissions: role?.permissions || {},
    },
  });

  async function onSubmit(data: FormData) {
    setIsLoading(true);
    try {
      const url = isEditing ? `/api/admin/roles/${role.id}` : "/api/admin/roles";
      const method = isEditing ? "PATCH" : "POST";

      const response = await fetch(url, {
        method,
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify(data),
      });

      if (!response.ok) {
        const result = await response.json();
        throw new Error(result.error || `Failed to ${isEditing ? "update" : "create"} role`);
      }

      toast.success(`Role ${isEditing ? "updated" : "created"} successfully`);
      router.push("/admin/roles");
      router.refresh();
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "An error occurred");
    } finally {
      setIsLoading(false);
    }
  }

  return (
    <Form {...form}>
      <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-8">
        <FormField
          control={form.control}
          name="name"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Name</FormLabel>
              <FormControl>
                <Input
                  placeholder="custom-role"
                  {...field}
                  disabled={isLoading || role?.is_system}
                />
              </FormControl>
              <FormDescription>
                Lowercase letters, numbers, and hyphens only
              </FormDescription>
              <FormMessage />
            </FormItem>
          )}
        />

        <FormField
          control={form.control}
          name="description"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Description</FormLabel>
              <FormControl>
                <Textarea
                  placeholder="Describe what this role is for..."
                  {...field}
                  disabled={isLoading}
                />
              </FormControl>
              <FormMessage />
            </FormItem>
          )}
        />

        <FormField
          control={form.control}
          name="permissions"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Permissions</FormLabel>
              <FormControl>
                <div className="border rounded-lg p-4">
                  <PermissionPicker
                    value={field.value}
                    onChange={field.onChange}
                    disabled={isLoading}
                  />
                </div>
              </FormControl>
              <FormDescription>
                Select the permissions this role should have
              </FormDescription>
              <FormMessage />
            </FormItem>
          )}
        />

        <div className="flex gap-4">
          <Button type="submit" disabled={isLoading}>
            {isLoading ? (
              <>
                <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                {isEditing ? "Saving..." : "Creating..."}
              </>
            ) : (
              <>
                <Save className="mr-2 h-4 w-4" />
                {isEditing ? "Save Changes" : "Create Role"}
              </>
            )}
          </Button>
          <Button
            type="button"
            variant="outline"
            onClick={() => router.back()}
            disabled={isLoading}
          >
            Cancel
          </Button>
        </div>
      </form>
    </Form>
  );
}