import { Button } from "@repo/shadcn-ui/components/button";
import { useId } from "react";

import { useDragReorder } from "../hooks/use-drag-reorder";
import { PlusIcon } from "../lib/icons";
import { removeTemplateSection } from "../lib/template-sections";

import type { FieldSection } from "./field-sections";
import { FormSectionTitle } from "./form-section-title";
import { ReorderDropIndicator } from "./reorder-drop-indicator";
import { ReorderHandle } from "./reorder-handle";
import { TemplateSectionEditor } from "./template-section-editor";
import { TemplateSectionFields } from "./template-section-fields";

export type SectionBinding = { fieldId: string; required: boolean; sectionId?: string | undefined };

export type SectionEditorLabels = {
  title: string;
  expand: string;
  collapse: string;
  fields: string;
  reorder: string;
  reorderHelp: string;
  add: string;
  name: string;
  description: string;
  ungrouped: string;
  moveUp: string;
  moveDown: string;
  remove: string;
  removeField: string;
  required: string;
  assign: string;
  help: string;
  empty: string;
};

export function TemplateSectionsEditor({
  sections,
  fields,
  fieldNames,
  fieldNotes,
  labels,
  disabled = false,
  createId,
  onChange,
  addFieldAction,
  fieldLayout = "cards",
  sectionLayout = "stack",
}: {
  fieldLayout?: "cards" | "compact";
  sectionLayout?: "stack" | "responsive";
  sections: readonly FieldSection[];
  fields: readonly SectionBinding[];
  fieldNames: Readonly<Record<string, string>>;
  fieldNotes?: Readonly<Record<string, string>> | undefined;
  labels: SectionEditorLabels;
  disabled?: boolean;
  createId: () => string;
  addFieldAction?: { label: string; onClick: (sectionId: string | undefined) => void };
  onChange: (value: { sections: FieldSection[]; fields: SectionBinding[] }) => void;
}) {
  const prefix = useId();

  const saveSections = (next: FieldSection[]) => onChange({ sections: next, fields: [...fields] });

  const { getHandleProps, getItemProps, getDropPlacement } = useDragReorder({
    items: sections,
    getId: (section) => section.id,
    disabled,
    onChange: saveSections,
  });

  const moveSection = (index: number, offset: number) => {
    const next = [...sections];
    const first = next[index];
    const second = next[index + offset];

    if (first && second) {
      next[index] = second;
      next[index + offset] = first;
      saveSections(next);
    }
  };

  const removeSection = (id: string) => onChange(removeTemplateSection(sections, fields, id));

  const fieldList = (sectionId?: string | undefined) => (
    <TemplateSectionFields
      addAction={
        addFieldAction
          ? {
              label: addFieldAction.label,
              onClick: () => addFieldAction.onClick(sectionId),
            }
          : undefined
      }
      disabled={disabled}
      fieldNames={fieldNames}
      fieldNotes={fieldNotes}
      fields={fields}
      labels={labels}
      layout={fieldLayout}
      onChange={(next) => onChange({ sections: [...sections], fields: next })}
      sectionId={sectionId}
      sections={sections}
    />
  );

  return (
    <section aria-labelledby={`${prefix}-title`} className="@container/template-sections space-y-4">
      <div className="flex flex-wrap items-center justify-between gap-3">
        <FormSectionTitle id={`${prefix}-title`}>{labels.title}</FormSectionTitle>
        <Button
          disabled={disabled || sections.length >= 30}
          onClick={() => saveSections([...sections, { id: createId(), name: "", description: "" }])}
          size="sm"
          type="button"
          variant="outline"
        >
          <PlusIcon aria-hidden="true" />
          {labels.add}
        </Button>
      </div>

      <p className="sr-only" id={`${prefix}-reorder-help`}>
        {labels.reorderHelp}
      </p>
      <div
        className={
          sectionLayout === "responsive"
            ? "grid grid-cols-1 items-stretch gap-4 @min-[1000px]/template-sections:grid-cols-2"
            : "space-y-5"
        }
      >
        {sections.map((section, index) => (
          <fieldset
            {...getItemProps(section.id)}
            className="relative min-w-0 overflow-hidden rounded-lg border border-border bg-muted/30 data-[dragging=true]:opacity-50"
            disabled={disabled}
            key={section.id}
          >
            <legend className="sr-only">{section.name || labels.name}</legend>
            <ReorderDropIndicator placement={getDropPlacement(section.id)} />
            <TemplateSectionEditor
              disabled={disabled}
              dragHandle={
                <ReorderHandle
                  {...getHandleProps(section.id)}
                  aria-describedby={`${prefix}-reorder-help`}
                  label={`${labels.reorder}: ${section.name || labels.name} (${index + 1}/${sections.length})`}
                />
              }
              index={index}
              labels={labels}
              onChange={(next) =>
                saveSections(sections.map((item) => (item.id === section.id ? next : item)))
              }
              onMove={(offset) => moveSection(index, offset)}
              onRemove={() => removeSection(section.id)}
              section={section}
              sectionCount={sections.length}
            >
              {fieldList(section.id)}
            </TemplateSectionEditor>
          </fieldset>
        ))}
      </div>
      {fieldList()}
    </section>
  );
}