import { useState } from "react";
import { useQuery, useMutation } from "@tanstack/react-query";
import { MainLayout } from "@/components/layouts/main-layout";
import { Organization, InsertOrganization } from "@shared/schema";
import { useAuth } from "@/hooks/use-auth";
import { useOrganization } from "@/context/organization-context";
import { apiRequest, queryClient } from "@/lib/queryClient";
import { useToast } from "@/hooks/use-toast";
import { useTheme } from "@/hooks/use-theme";
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import { z } from "zod";
import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/components/ui/card";
import {
  Form,
  FormControl,
  FormDescription,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from "@/components/ui/form";
import {
  Tabs,
  TabsContent,
  TabsList,
  TabsTrigger,
} from "@/components/ui/tabs";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "@/components/ui/select";
import {
  AlertDialog,
  AlertDialogAction,
  AlertDialogCancel,
  AlertDialogContent,
  AlertDialogDescription,
  AlertDialogFooter,
  AlertDialogHeader,
  AlertDialogTitle,
} from "@/components/ui/alert-dialog";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Switch } from "@/components/ui/switch";
import { Separator } from "@/components/ui/separator";
import { Loader2, Moon, Sun, Lock, Laptop } from "lucide-react";

// Organization form schema
const organizationFormSchema = z.object({
  name: z.string().min(1, "Organization name is required"),
  isActive: z.boolean().default(true),
});

// Create organization form schema
const createOrganizationFormSchema = z.object({
  name: z.string().min(1, "Organization name is required"),
  isActive: z.boolean().default(true),
});

// Account form schema
const accountFormSchema = z.object({
  username: z.string().min(3, "Username must be at least 3 characters"),
  email: z.string().email("Please enter a valid email"),
  fullName: z.string().optional(),
});

// Password form schema
const passwordFormSchema = z.object({
  currentPassword: z.string().min(1, "Current password is required"),
  newPassword: z.string().min(8, "New password must be at least 8 characters"),
  confirmPassword: z.string().min(8, "Please confirm your new password"),
}).refine((data) => data.newPassword === data.confirmPassword, {
  message: "Passwords don't match",
  path: ["confirmPassword"],
});

export default function SettingsPage() {
  const { toast } = useToast();
  const { user } = useAuth();
  const { theme, setTheme } = useTheme();
  const { currentOrganization, setCurrentOrganization, createOrganizationMutation } = useOrganization();
  
  const [isDeleteDialogOpen, setIsDeleteDialogOpen] = useState(false);
  
  // Create organization form
  const createOrganizationForm = useForm<z.infer<typeof createOrganizationFormSchema>>({
    resolver: zodResolver(createOrganizationFormSchema),
    defaultValues: {
      name: "",
      isActive: true,
    },
  });
  
  // Fetch organization data
  const { data: organization } = useQuery<Organization>({
    queryKey: ["/api/organizations", currentOrganization?.id],
    enabled: !!currentOrganization?.id,
  });

  // Organization form
  const organizationForm = useForm<z.infer<typeof organizationFormSchema>>({
    resolver: zodResolver(organizationFormSchema),
    defaultValues: {
      name: currentOrganization?.name || "",
      isActive: currentOrganization?.isActive,
    },
  });

  // Account form
  const accountForm = useForm<z.infer<typeof accountFormSchema>>({
    resolver: zodResolver(accountFormSchema),
    defaultValues: {
      username: user?.username || "",
      email: user?.email || "",
      fullName: user?.fullName || "",
    },
  });

  // Password form
  const passwordForm = useForm<z.infer<typeof passwordFormSchema>>({
    resolver: zodResolver(passwordFormSchema),
    defaultValues: {
      currentPassword: "",
      newPassword: "",
      confirmPassword: "",
    },
  });

  // Update organization details when they change
  useState(() => {
    if (currentOrganization) {
      organizationForm.reset({
        name: currentOrganization.name,
        isActive: currentOrganization.isActive,
      });
    }
  });

  // Update organization mutation
  const updateOrganizationMutation = useMutation({
    mutationFn: async (data: z.infer<typeof organizationFormSchema>) => {
      if (!currentOrganization) throw new Error("No organization selected");
      
      const res = await apiRequest("PUT", `/api/organizations/${currentOrganization.id}`, data);
      return await res.json();
    },
    onSuccess: (data) => {
      queryClient.invalidateQueries({ queryKey: ["/api/organizations"] });
      queryClient.invalidateQueries({ queryKey: ["/api/organizations", currentOrganization?.id] });
      
      // Update the current organization in context
      if (currentOrganization) {
        setCurrentOrganization({
          ...currentOrganization,
          ...data,
        });
      }
      
      toast({
        title: "Organization updated",
        description: "The organization details have been updated successfully.",
      });
    },
    onError: (error) => {
      toast({
        title: "Failed to update organization",
        description: error.message,
        variant: "destructive",
      });
    },
  });

  // Update account mutation
  const updateAccountMutation = useMutation({
    mutationFn: async (data: z.infer<typeof accountFormSchema>) => {
      if (!user) throw new Error("Not authenticated");
      
      const res = await apiRequest("PUT", `/api/users/${user.id}`, data);
      return await res.json();
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ["/api/user"] });
      
      toast({
        title: "Account updated",
        description: "Your account details have been updated successfully.",
      });
    },
    onError: (error) => {
      toast({
        title: "Failed to update account",
        description: error.message,
        variant: "destructive",
      });
    },
  });

  // Change password mutation
  const changePasswordMutation = useMutation({
    mutationFn: async (data: z.infer<typeof passwordFormSchema>) => {
      if (!user) throw new Error("Not authenticated");
      
      const res = await apiRequest("POST", "/api/change-password", {
        currentPassword: data.currentPassword,
        newPassword: data.newPassword,
      });
      return await res.json();
    },
    onSuccess: () => {
      passwordForm.reset();
      
      toast({
        title: "Password changed",
        description: "Your password has been changed successfully.",
      });
    },
    onError: (error) => {
      toast({
        title: "Failed to change password",
        description: error.message,
        variant: "destructive",
      });
    },
  });

  // Delete organization mutation
  const deleteOrganizationMutation = useMutation({
    mutationFn: async () => {
      if (!currentOrganization) throw new Error("No organization selected");
      
      await apiRequest("DELETE", `/api/organizations/${currentOrganization.id}`);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ["/api/organizations"] });
      setIsDeleteDialogOpen(false);
      
      toast({
        title: "Organization deleted",
        description: "The organization has been deleted successfully.",
      });
    },
    onError: (error) => {
      toast({
        title: "Failed to delete organization",
        description: error.message,
        variant: "destructive",
      });
    },
  });

  // Form submission handlers
  const onOrganizationSubmit = (data: z.infer<typeof organizationFormSchema>) => {
    updateOrganizationMutation.mutate(data);
  };

  const onAccountSubmit = (data: z.infer<typeof accountFormSchema>) => {
    updateAccountMutation.mutate(data);
  };

  const onPasswordSubmit = (data: z.infer<typeof passwordFormSchema>) => {
    changePasswordMutation.mutate(data);
  };

  // Check if current user has admin/manager permission
  const hasManagePermission = user?.role === "admin" || user?.role === "manager";

  return (
    <MainLayout
      title="Settings"
      description="Manage your account and organization settings."
    >
      <Tabs defaultValue="account" className="space-y-6">
        <TabsList className="w-full sm:w-auto">
          <TabsTrigger value="account">Account</TabsTrigger>
          <TabsTrigger value="organization">Organization</TabsTrigger>
          <TabsTrigger value="appearance">Appearance</TabsTrigger>
        </TabsList>
        
        {/* Account Settings */}
        <TabsContent value="account" className="space-y-6">
          <Card>
            <CardHeader>
              <CardTitle>Account Information</CardTitle>
              <CardDescription>
                Update your personal account details.
              </CardDescription>
            </CardHeader>
            <CardContent>
              <Form {...accountForm}>
                <form onSubmit={accountForm.handleSubmit(onAccountSubmit)} className="space-y-4">
                  <FormField
                    control={accountForm.control}
                    name="username"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>Username</FormLabel>
                        <FormControl>
                          <Input {...field} />
                        </FormControl>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <FormField
                    control={accountForm.control}
                    name="email"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>Email</FormLabel>
                        <FormControl>
                          <Input type="email" {...field} />
                        </FormControl>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <FormField
                    control={accountForm.control}
                    name="fullName"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>Full Name</FormLabel>
                        <FormControl>
                          <Input {...field} value={field.value || ""} />
                        </FormControl>
                        <FormDescription>
                          Your full name for display purposes
                        </FormDescription>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <Button 
                    type="submit" 
                    disabled={updateAccountMutation.isPending}
                  >
                    {updateAccountMutation.isPending ? (
                      <>
                        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                        Saving...
                      </>
                    ) : (
                      "Save Changes"
                    )}
                  </Button>
                </form>
              </Form>
            </CardContent>
          </Card>
          
          <Card>
            <CardHeader>
              <CardTitle>Change Password</CardTitle>
              <CardDescription>
                Update your account password.
              </CardDescription>
            </CardHeader>
            <CardContent>
              <Form {...passwordForm}>
                <form onSubmit={passwordForm.handleSubmit(onPasswordSubmit)} className="space-y-4">
                  <FormField
                    control={passwordForm.control}
                    name="currentPassword"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>Current Password</FormLabel>
                        <FormControl>
                          <Input type="password" {...field} />
                        </FormControl>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <FormField
                    control={passwordForm.control}
                    name="newPassword"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>New Password</FormLabel>
                        <FormControl>
                          <Input type="password" {...field} />
                        </FormControl>
                        <FormDescription>
                          Must be at least 8 characters long
                        </FormDescription>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <FormField
                    control={passwordForm.control}
                    name="confirmPassword"
                    render={({ field }) => (
                      <FormItem>
                        <FormLabel>Confirm New Password</FormLabel>
                        <FormControl>
                          <Input type="password" {...field} />
                        </FormControl>
                        <FormMessage />
                      </FormItem>
                    )}
                  />
                  
                  <Button 
                    type="submit" 
                    disabled={changePasswordMutation.isPending}
                  >
                    {changePasswordMutation.isPending ? (
                      <>
                        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                        Changing Password...
                      </>
                    ) : (
                      "Change Password"
                    )}
                  </Button>
                </form>
              </Form>
            </CardContent>
          </Card>
        </TabsContent>
        
        {/* Organization Settings */}
        <TabsContent value="organization" className="space-y-6">
          {!hasManagePermission ? (
            <Card>
              <CardContent className="pt-6 flex flex-col items-center justify-center h-64">
                <Lock className="h-12 w-12 text-muted-foreground mb-4" />
                <h3 className="text-lg font-medium mb-2">Access Restricted</h3>
                <p className="text-center text-muted-foreground">
                  You don't have permission to modify organization settings. Only administrators and managers can manage organizations.
                </p>
              </CardContent>
            </Card>
          ) : (
            <>
              {user?.role === "admin" && (
                <Card>
                  <CardHeader>
                    <CardTitle>Create New Organization</CardTitle>
                    <CardDescription>
                      Add a new organization to your account
                    </CardDescription>
                  </CardHeader>
                  <CardContent>
                    <Form {...createOrganizationForm}>
                      <form 
                        onSubmit={createOrganizationForm.handleSubmit((data) => {
                          createOrganizationMutation.mutate(data);
                          createOrganizationForm.reset();
                        })} 
                        className="space-y-4"
                      >
                        <FormField
                          control={createOrganizationForm.control}
                          name="name"
                          render={({ field }) => (
                            <FormItem>
                              <FormLabel>Organization Name</FormLabel>
                              <FormControl>
                                <Input {...field} placeholder="Enter organization name" />
                              </FormControl>
                              <FormMessage />
                            </FormItem>
                          )}
                        />
                        
                        <FormField
                          control={createOrganizationForm.control}
                          name="isActive"
                          render={({ field }) => (
                            <FormItem className="flex flex-row items-center justify-between rounded-lg border p-4">
                              <div className="space-y-0.5">
                                <FormLabel className="text-base">Active Status</FormLabel>
                                <FormDescription>
                                  Enable this organization upon creation
                                </FormDescription>
                              </div>
                              <FormControl>
                                <Switch
                                  checked={field.value}
                                  onCheckedChange={field.onChange}
                                />
                              </FormControl>
                            </FormItem>
                          )}
                        />
                        
                        <Button 
                          type="submit" 
                          disabled={createOrganizationMutation.isPending}
                        >
                          {createOrganizationMutation.isPending ? (
                            <>
                              <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                              Creating...
                            </>
                          ) : (
                            "Create Organization"
                          )}
                        </Button>
                      </form>
                    </Form>
                  </CardContent>
                </Card>
              )}
            
              <Card>
                <CardHeader>
                  <CardTitle>Organization Details</CardTitle>
                  <CardDescription>
                    Manage your organization information.
                  </CardDescription>
                </CardHeader>
                <CardContent>
                  <Form {...organizationForm}>
                    <form onSubmit={organizationForm.handleSubmit(onOrganizationSubmit)} className="space-y-4">
                      <FormField
                        control={organizationForm.control}
                        name="name"
                        render={({ field }) => (
                          <FormItem>
                            <FormLabel>Organization Name</FormLabel>
                            <FormControl>
                              <Input {...field} />
                            </FormControl>
                            <FormMessage />
                          </FormItem>
                        )}
                      />
                      
                      <FormField
                        control={organizationForm.control}
                        name="isActive"
                        render={({ field }) => (
                          <FormItem className="flex flex-row items-center justify-between rounded-lg border p-4">
                            <div className="space-y-0.5">
                              <FormLabel className="text-base">Active Status</FormLabel>
                              <FormDescription>
                                Enable or disable this organization
                              </FormDescription>
                            </div>
                            <FormControl>
                              <Switch
                                checked={field.value}
                                onCheckedChange={field.onChange}
                              />
                            </FormControl>
                          </FormItem>
                        )}
                      />
                      
                      <Button 
                        type="submit" 
                        disabled={updateOrganizationMutation.isPending}
                      >
                        {updateOrganizationMutation.isPending ? (
                          <>
                            <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                            Saving...
                          </>
                        ) : (
                          "Save Changes"
                        )}
                      </Button>
                    </form>
                  </Form>
                </CardContent>
              </Card>
              
              {user?.role === "admin" && (
                <Card className="border-destructive">
                  <CardHeader>
                    <CardTitle>Danger Zone</CardTitle>
                    <CardDescription>
                      Irreversible actions for your organization
                    </CardDescription>
                  </CardHeader>
                  <CardContent>
                    <div className="space-y-4">
                      <div className="rounded-lg border border-destructive p-4">
                        <div className="flex flex-row items-center justify-between">
                          <div>
                            <h4 className="font-medium">Delete Organization</h4>
                            <p className="text-sm text-muted-foreground">
                              Permanently delete this organization and all associated data
                            </p>
                          </div>
                          <Button 
                            variant="destructive" 
                            onClick={() => setIsDeleteDialogOpen(true)}
                          >
                            Delete
                          </Button>
                        </div>
                      </div>
                    </div>
                  </CardContent>
                </Card>
              )}
            </>
          )}
        </TabsContent>
        
        {/* Appearance Settings */}
        <TabsContent value="appearance" className="space-y-6">
          <Card>
            <CardHeader>
              <CardTitle>Appearance</CardTitle>
              <CardDescription>
                Customize the application appearance and theme.
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-6">
              <div className="space-y-2">
                <h3 className="text-lg font-medium">Theme</h3>
                <p className="text-sm text-muted-foreground">
                  Select your preferred theme appearance
                </p>
                <div className="grid grid-cols-3 gap-4 pt-2">
                  <div
                    className={`flex flex-col items-center justify-between rounded-md border-2 border-muted bg-popover p-4 hover:bg-accent hover:text-accent-foreground cursor-pointer ${
                      theme === "light" ? "border-primary" : ""
                    }`}
                    onClick={() => setTheme("light")}
                  >
                    <Sun className="h-6 w-6 mb-3" />
                    <div className="space-y-1 text-center">
                      <h3 className="font-medium">Light</h3>
                      <p className="text-xs text-muted-foreground">Light background with dark text</p>
                    </div>
                  </div>
                  <div
                    className={`flex flex-col items-center justify-between rounded-md border-2 border-muted bg-popover p-4 hover:bg-accent hover:text-accent-foreground cursor-pointer ${
                      theme === "dark" ? "border-primary" : ""
                    }`}
                    onClick={() => setTheme("dark")}
                  >
                    <Moon className="h-6 w-6 mb-3" />
                    <div className="space-y-1 text-center">
                      <h3 className="font-medium">Dark</h3>
                      <p className="text-xs text-muted-foreground">Dark background with light text</p>
                    </div>
                  </div>
                  <div
                    className={`flex flex-col items-center justify-between rounded-md border-2 border-muted bg-popover p-4 hover:bg-accent hover:text-accent-foreground cursor-pointer ${
                      theme === "system" ? "border-primary" : ""
                    }`}
                    onClick={() => setTheme("system")}
                  >
                    <Laptop className="h-6 w-6 mb-3" />
                    <div className="space-y-1 text-center">
                      <h3 className="font-medium">System</h3>
                      <p className="text-xs text-muted-foreground">Follow your system preference</p>
                    </div>
                  </div>
                </div>
              </div>
            </CardContent>
          </Card>
        </TabsContent>
      </Tabs>

      {/* Delete Organization Dialog */}
      <AlertDialog open={isDeleteDialogOpen} onOpenChange={setIsDeleteDialogOpen}>
        <AlertDialogContent>
          <AlertDialogHeader>
            <AlertDialogTitle>Delete Organization</AlertDialogTitle>
            <AlertDialogDescription>
              Are you sure you want to delete the organization <strong>{currentOrganization?.name}</strong>?
              This action cannot be undone. All domains, DNS records, and related data will be permanently deleted.
            </AlertDialogDescription>
          </AlertDialogHeader>
          <AlertDialogFooter>
            <AlertDialogCancel>Cancel</AlertDialogCancel>
            <AlertDialogAction 
              onClick={() => deleteOrganizationMutation.mutate()}
              className="bg-destructive text-destructive-foreground hover:bg-destructive/90"
              disabled={deleteOrganizationMutation.isPending}
            >
              {deleteOrganizationMutation.isPending ? (
                <>
                  <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                  Deleting...
                </>
              ) : (
                "Delete Organization"
              )}
            </AlertDialogAction>
          </AlertDialogFooter>
        </AlertDialogContent>
      </AlertDialog>
    </MainLayout>
  );
}