import {
  AddAnimationTrackCommand,
  RetargetAnimationTrackCommand,
} from '../../core/commands/animationCommands';
import { animationTargets, targetDefs, trackDef } from '../../core/model/animation';
import type { AnimationAsset, AnimationTrack } from '../../core/model/Asset';
import { findAsset } from '../../core/model/Project';
import type { PropertyDef } from '../../core/properties/PropertySchema';
import { type Button, Dropdown, Label, Menu, type MenuItem } from '../../ui';
import { dialogSlot, FormDialog } from '../FormDialog';
import { type EditorState, trackSelection } from '../state';

const PICKER_WIDTH = 240;

const slot = dialogSlot<RowDialog>();

/** The open row dialog, for the check scripts. */
export const currentRowDialog = slot.current;

/** Opens the dialog centred, closing whichever one was open before it. */
export const openRowDialog = slot.open;

/** One choice of the object picker: the root itself (`''`) or an object inside it. */
interface TargetChoice {
  id: string;
  label: string;
}

/**
 * Adds a row to the timeline, or aims an existing one elsewhere: first the object – the animated
 * asset itself, or one placed inside it when that is a container or scene – then a property of
 * it. Retargeting offers only properties of the row's kind, since its keys stay (#97).
 */
export class RowDialog extends FormDialog {
  private target: string;
  private property: string;
  private readonly targetButton: Dropdown;
  private readonly propertyButton: Dropdown;
  private readonly summary: Label;
  private readonly confirm: Button;

  constructor(
    private readonly state: EditorState,
    private readonly asset: AnimationAsset,
    private readonly track: AnimationTrack | null = null,
  ) {
    super(360, track ? 'Change what the row animates' : `Add a row to "${asset.name}"`);
    this.target = track?.target ?? '';
    this.property = track?.property ?? '';
    const root = findAsset(state.project, asset.root);
    this.content.add(new Label(`Animates ${root ? `"${root.name}"` : 'nothing yet'}`, { style: 'muted' }));

    this.targetButton = new Dropdown('', { width: PICKER_WIDTH, onClick: () => this.openTargets() });
    this.content.add(this.formRow(this.fieldLabel('Object'), this.targetButton));
    this.propertyButton = new Dropdown('', { width: PICKER_WIDTH, onClick: () => this.openProperties() });
    this.content.add(this.formRow(this.fieldLabel('Property'), this.propertyButton));

    this.summary = new Label('', { style: 'muted' });
    this.content.add(this.summary);

    this.confirm = this.addButtons(track ? 'Change' : 'Add row', 'primary', () => this.apply());

    // Without a property yet, the first one the object offers is as good a start as any.
    if (!this.property) this.property = this.properties()[0]?.key ?? '';
    this.refresh();
  }

  /** What the dialog offers and holds, for the check scripts. */
  debugInfo(): { target: string; property: string; targets: string[]; properties: string[]; ok: boolean } {
    return {
      target: this.target,
      property: this.property,
      targets: this.targets().map((t) => t.label),
      properties: this.properties().map((d) => d.label),
      ok: this.confirm.enabled,
    };
  }

  /** Picks by id / key rather than by click, for the check scripts. */
  pick(target: string, property: string): void {
    this.target = target;
    this.property = property;
    this.refresh();
  }

  private targets(): TargetChoice[] {
    const root = findAsset(this.state.project, this.asset.root);
    if (!root) return [];
    const choices: TargetChoice[] = [{ id: '', label: `${root.name} (itself)` }];
    for (const { id, object, depth } of animationTargets(this.state.project, root))
      choices.push({
        id,
        label: `${'   '.repeat(depth)}${object.name || findAsset(this.state.project, object.assetId)?.name || '?'}`,
      });
    return choices;
  }

  /** The properties the picked object offers, less those another row already animates. */
  private properties(): PropertyDef[] {
    const defs = targetDefs(this.state.project, this.asset, this.target);
    if (!defs) return [];
    const was = this.trackKind();
    return defs.filter((def) => {
      if (was !== null && def.kind !== was) return false;
      return !this.asset.tracks.some(
        (t) => t.id !== this.track?.id && t.target === this.target && t.property === def.key,
      );
    });
  }

  /** The kind the row being changed has; null when its target or property is gone, so it may go anywhere. */
  private trackKind(): string | null {
    return this.track ? (trackDef(this.state.project, this.asset, this.track)?.kind ?? null) : null;
  }

  private openTargets(): void {
    const items: MenuItem[] = this.targets().map((choice) => ({
      label: choice.label,
      current: choice.id === this.target,
      onSelect: () => {
        this.target = choice.id;
        // Another object may not have the property; fall back to its first.
        if (!this.properties().some((d) => d.key === this.property))
          this.property = this.properties()[0]?.key ?? '';
        this.refresh();
      },
    }));
    new Menu(items, { searchable: items.length > 9 }).openBelow(this.targetButton);
  }

  private openProperties(): void {
    const items: MenuItem[] = this.properties().map((def) => ({
      label: def.label,
      current: def.key === this.property,
      onSelect: () => {
        this.property = def.key;
        this.refresh();
      },
    }));
    if (items.length === 0) items.push({ label: 'Nothing left to animate here', onSelect: () => undefined });
    new Menu(items, { searchable: true }).openBelow(this.propertyButton);
  }

  private refresh(): void {
    const target = this.targets().find((t) => t.id === this.target);
    this.targetButton.setText(target ? target.label.trim() : this.target === '' ? '—' : '(missing)');
    const def = this.properties().find((d) => d.key === this.property);
    this.propertyButton.setText(def ? def.label : '—');
    const ok = Boolean(target && def);
    this.summary.setText(
      !target
        ? 'Pick the animated asset first.'
        : !def
          ? 'Pick a property.'
          : `Keys on this row set ${def.label} (${def.kind}) of ${target.label.trim()}.`,
    );
    this.confirm.setEnabled(ok);
    this.refreshLayout();
  }

  private apply(): void {
    if (this.track) {
      this.state.execute(
        new RetargetAnimationTrackCommand(this.asset.id, this.track.id, this.target, this.property),
      );
      return;
    }
    const command = new AddAnimationTrackCommand(this.asset.id, this.target, this.property);
    if (this.state.execute(command)) this.state.select(trackSelection(this.asset.id, [], command.trackId));
  }
}