"use client";

import {
  createNoteAction,
  updateNoteAction,
} from "@/app/(dashboard)/anotacoes/actions";
import { Button } from "@/components/ui/button";
import { Checkbox } from "@/components/ui/checkbox";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
  DialogTrigger,
} from "@/components/ui/dialog";
import { Input } from "@/components/ui/input";
import { RadioGroup, RadioGroupItem } from "@/components/ui/radio-group";
import { Textarea } from "@/components/ui/textarea";
import { useControlledState } from "@/hooks/use-controlled-state";
import { useFormState } from "@/hooks/use-form-state";
import { PlusIcon, Trash2Icon } from "lucide-react";
import {
  type ReactNode,
  useCallback,
  useEffect,
  useRef,
  useState,
  useTransition,
} from "react";
import { toast } from "sonner";
import type { Note, NoteFormValues, Task } from "./types";

type NoteDialogMode = "create" | "update";
interface NoteDialogProps {
  mode: NoteDialogMode;
  trigger?: ReactNode;
  note?: Note;
  open?: boolean;
  onOpenChange?: (open: boolean) => void;
}

const MAX_TITLE = 30;
const MAX_DESC = 350;
const normalize = (s: string) => s.replace(/\s+/g, " ").trim();

const buildInitialValues = (note?: Note): NoteFormValues => ({
  title: note?.title ?? "",
  description: note?.description ?? "",
  type: note?.type ?? "nota",
  tasks: note?.tasks ?? [],
});

const generateTaskId = () => {
  return `task-${Date.now()}-${Math.random().toString(36).substring(2, 9)}`;
};

export function NoteDialog({
  mode,
  trigger,
  note,
  open,
  onOpenChange,
}: NoteDialogProps) {
  const [isPending, startTransition] = useTransition();
  const [errorMessage, setErrorMessage] = useState<string | null>(null);
  const [newTaskText, setNewTaskText] = useState("");

  const titleRef = useRef<HTMLInputElement>(null);
  const descRef = useRef<HTMLTextAreaElement>(null);
  const newTaskRef = useRef<HTMLInputElement>(null);

  // Use controlled state hook for dialog open state
  const [dialogOpen, setDialogOpen] = useControlledState(
    open,
    false,
    onOpenChange
  );

  const initialState = buildInitialValues(note);

  // Use form state hook for form management
  const { formState, updateField, setFormState } =
    useFormState<NoteFormValues>(initialState);

  useEffect(() => {
    if (dialogOpen) {
      setFormState(buildInitialValues(note));
      setErrorMessage(null);
      setNewTaskText("");
      requestAnimationFrame(() => titleRef.current?.focus());
    }
  }, [dialogOpen, note, setFormState]);

  const title = mode === "create" ? "Nova anotação" : "Editar anotação";
  const description =
    mode === "create"
      ? "Escolha entre uma nota simples ou uma lista de tarefas."
      : "Altere o título e/ou conteúdo desta anotação.";
  const submitLabel =
    mode === "create" ? "Salvar anotação" : "Atualizar anotação";

  const titleCount = formState.title.length;
  const descCount = formState.description.length;
  const isNote = formState.type === "nota";

  const onlySpaces =
    normalize(formState.title).length === 0 ||
    (isNote && normalize(formState.description).length === 0) ||
    (!isNote && (!formState.tasks || formState.tasks.length === 0));

  const invalidLen = titleCount > MAX_TITLE || descCount > MAX_DESC;

  const unchanged =
    mode === "update" &&
    normalize(formState.title) === normalize(note?.title ?? "") &&
    normalize(formState.description) === normalize(note?.description ?? "") &&
    JSON.stringify(formState.tasks) === JSON.stringify(note?.tasks);

  const disableSubmit = isPending || onlySpaces || unchanged || invalidLen;

  const handleOpenChange = useCallback(
    (v: boolean) => {
      setDialogOpen(v);
      if (!v) setErrorMessage(null);
    },
    [setDialogOpen]
  );

  const handleKeyDown = useCallback(
    (e: React.KeyboardEvent) => {
      if ((e.ctrlKey || e.metaKey) && e.key === "Enter")
        (e.currentTarget as HTMLFormElement).requestSubmit();
      if (e.key === "Escape") handleOpenChange(false);
    },
    [handleOpenChange]
  );

  const handleAddTask = useCallback(() => {
    const text = normalize(newTaskText);
    if (!text) return;

    const newTask: Task = {
      id: generateTaskId(),
      text,
      completed: false,
    };

    updateField("tasks", [...(formState.tasks || []), newTask]);
    setNewTaskText("");
    requestAnimationFrame(() => newTaskRef.current?.focus());
  }, [newTaskText, formState.tasks, updateField]);

  const handleRemoveTask = useCallback(
    (taskId: string) => {
      updateField(
        "tasks",
        (formState.tasks || []).filter((t) => t.id !== taskId)
      );
    },
    [formState.tasks, updateField]
  );

  const handleToggleTask = useCallback(
    (taskId: string) => {
      updateField(
        "tasks",
        (formState.tasks || []).map((t) =>
          t.id === taskId ? { ...t, completed: !t.completed } : t
        )
      );
    },
    [formState.tasks, updateField]
  );

  const handleSubmit = useCallback(
    (e: React.FormEvent<HTMLFormElement>) => {
      e.preventDefault();
      setErrorMessage(null);

      const payload = {
        title: normalize(formState.title),
        description: normalize(formState.description),
        type: formState.type,
        tasks: formState.tasks,
      };

      if (onlySpaces || invalidLen) {
        setErrorMessage("Preencha os campos respeitando os limites.");
        titleRef.current?.focus();
        return;
      }

      if (mode === "update" && !note?.id) {
        const msg = "Não foi possível identificar a anotação a ser editada.";
        setErrorMessage(msg);
        toast.error(msg);
        return;
      }

      if (unchanged) {
        toast.info("Nada para atualizar.");
        return;
      }

      startTransition(async () => {
        let result;
        if (mode === "create") {
          result = await createNoteAction(payload);
        } else {
          if (!note?.id) {
            const msg = "ID da anotação não encontrado.";
            setErrorMessage(msg);
            toast.error(msg);
            return;
          }
          result = await updateNoteAction({ id: note.id, ...payload });
        }

        if (result.success) {
          toast.success(result.message);
          setDialogOpen(false);
          return;
        }
        setErrorMessage(result.error);
        toast.error(result.error);
        titleRef.current?.focus();
      });
    },
    [
      formState.title,
      formState.description,
      formState.type,
      formState.tasks,
      mode,
      note,
      setDialogOpen,
      onlySpaces,
      unchanged,
      invalidLen,
    ]
  );

  return (
    <Dialog open={dialogOpen} onOpenChange={handleOpenChange}>
      {trigger ? <DialogTrigger asChild>{trigger}</DialogTrigger> : null}
      <DialogContent className="max-h-[90vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle>{title}</DialogTitle>
          <DialogDescription>{description}</DialogDescription>
        </DialogHeader>

        <form
          className="space-y-4"
          onSubmit={handleSubmit}
          onKeyDown={handleKeyDown}
          noValidate
        >
          {/* Seletor de Tipo - apenas no modo de criação */}
          {mode === "create" && (
            <div className="space-y-3">
              <label className="text-sm font-medium text-foreground">
                Tipo de anotação
              </label>
              <RadioGroup
                value={formState.type}
                onValueChange={(value) =>
                  updateField("type", value as "nota" | "tarefa")
                }
                disabled={isPending}
                className="flex gap-4"
              >
                <div className="flex items-center gap-2">
                  <RadioGroupItem value="nota" id="tipo-nota" />
                  <label
                    htmlFor="tipo-nota"
                    className="text-sm cursor-pointer select-none"
                  >
                    Nota
                  </label>
                </div>
                <div className="flex items-center gap-2">
                  <RadioGroupItem value="tarefa" id="tipo-tarefa" />
                  <label
                    htmlFor="tipo-tarefa"
                    className="text-sm cursor-pointer select-none"
                  >
                    Tarefas
                  </label>
                </div>
              </RadioGroup>
            </div>
          )}

          {/* Título */}
          <div className="space-y-2">
            <label
              htmlFor="note-title"
              className="text-sm font-medium text-foreground"
            >
              Título
            </label>
            <Input
              id="note-title"
              ref={titleRef}
              value={formState.title}
              onChange={(e) => updateField("title", e.target.value)}
              placeholder={
                isNote ? "Ex.: Revisar metas do mês" : "Ex.: Tarefas da semana"
              }
              maxLength={MAX_TITLE}
              disabled={isPending}
              aria-describedby="note-title-help"
              required
            />
            <p
              id="note-title-help"
              className="text-xs text-muted-foreground"
              aria-live="polite"
            >
              Até {MAX_TITLE} caracteres. Restantes:{" "}
              {Math.max(0, MAX_TITLE - titleCount)}.
            </p>
          </div>

          {/* Conteúdo - apenas para Notas */}
          {isNote && (
            <div className="space-y-2">
              <label
                htmlFor="note-description"
                className="text-sm font-medium text-foreground"
              >
                Conteúdo
              </label>
              <Textarea
                id="note-description"
                className="field-sizing-fixed"
                ref={descRef}
                value={formState.description}
                onChange={(e) => updateField("description", e.target.value)}
                placeholder="Detalhe sua anotação..."
                rows={6}
                maxLength={MAX_DESC}
                disabled={isPending}
                aria-describedby="note-desc-help"
                required
              />
              <p
                id="note-desc-help"
                className="text-xs text-muted-foreground"
                aria-live="polite"
              >
                Até {MAX_DESC} caracteres. Restantes:{" "}
                {Math.max(0, MAX_DESC - descCount)}.
              </p>
            </div>
          )}

          {/* Lista de Tarefas - apenas para Tarefas */}
          {!isNote && (
            <div className="space-y-4">
              <div className="space-y-2">
                <label
                  htmlFor="new-task-input"
                  className="text-sm font-medium text-foreground"
                >
                  Adicionar tarefa
                </label>
                <div className="flex gap-2">
                  <Input
                    id="new-task-input"
                    ref={newTaskRef}
                    value={newTaskText}
                    onChange={(e) => setNewTaskText(e.target.value)}
                    placeholder="Ex.: Comprar ingredientes para o jantar"
                    disabled={isPending}
                    onKeyDown={(e) => {
                      if (e.key === "Enter") {
                        e.preventDefault();
                        handleAddTask();
                      }
                    }}
                  />
                  <Button
                    type="button"
                    onClick={handleAddTask}
                    disabled={isPending || !normalize(newTaskText)}
                    className="shrink-0"
                  >
                    <PlusIcon className="h-4 w-4" />
                  </Button>
                </div>
                <p className="text-xs text-muted-foreground">
                  Pressione Enter ou clique no botão + para adicionar
                </p>
              </div>

              {/* Lista de tarefas existentes */}
              {formState.tasks && formState.tasks.length > 0 && (
                <div className="space-y-2">
                  <label className="text-sm font-medium text-foreground">
                    Tarefas ({formState.tasks.length})
                  </label>
                  <div className="space-y-2 max-h-[240px] overflow-y-auto pr-1">
                    {formState.tasks.map((task) => (
                      <div
                        key={task.id}
                        className="flex items-center gap-3 p-3 rounded-lg border bg-card hover:bg-accent/50 transition-colors"
                      >
                        <Checkbox
                          checked={task.completed}
                          onCheckedChange={() => handleToggleTask(task.id)}
                          disabled={isPending}
                          aria-label={`Marcar tarefa "${task.text}" como ${
                            task.completed ? "não concluída" : "concluída"
                          }`}
                        />
                        <span
                          className={`flex-1 text-sm wrap-break-word ${
                            task.completed
                              ? "line-through text-muted-foreground"
                              : "text-foreground"
                          }`}
                        >
                          {task.text}
                        </span>
                        <Button
                          type="button"
                          variant="ghost"
                          size="sm"
                          onClick={() => handleRemoveTask(task.id)}
                          disabled={isPending}
                          className="h-8 w-8 p-0 shrink-0 text-muted-foreground hover:text-destructive"
                          aria-label={`Remover tarefa "${task.text}"`}
                        >
                          <Trash2Icon className="h-4 w-4" />
                        </Button>
                      </div>
                    ))}
                  </div>
                </div>
              )}
            </div>
          )}

          {errorMessage ? (
            <p className="text-sm text-destructive" role="alert">
              {errorMessage}
            </p>
          ) : null}

          <DialogFooter>
            <Button
              type="button"
              variant="outline"
              onClick={() => handleOpenChange(false)}
              disabled={isPending}
            >
              Cancelar
            </Button>
            <Button type="submit" disabled={disableSubmit}>
              {isPending ? "Salvando..." : submitLabel}
            </Button>
          </DialogFooter>
        </form>
      </DialogContent>
    </Dialog>
  );
}