import { TimeSliderCore, TimeSliderDataAttrs } from '@videojs/core';
import {
  applyStateDataAttrs,
  createSlider,
  getTimeSliderCSSVars,
  logMissingFeature,
  type SliderHandle,
  selectBuffer,
  selectTime,
} from '@videojs/core/dom';
import type { PropertyDeclarationMap, PropertyValues } from '@videojs/element';
import { ContextProvider } from '@videojs/element/context';
import { applyStyles, isRTL } from '@videojs/utils/dom';

import { playerContext } from '../../player/context';
import { PlayerController } from '../../player/player-controller';
import { MediaElement } from '../media-element';
import { sliderContext } from '../slider/slider-context';

export class TimeSliderElement extends MediaElement {
  static readonly tagName = 'media-time-slider';

  static override properties = {
    label: { type: String },
    commitThrottle: { type: Number, attribute: 'commit-throttle' },
    step: { type: Number },
    largeStep: { type: Number, attribute: 'large-step' },
    orientation: { type: String },
    disabled: { type: Boolean },
    thumbAlignment: { type: String, attribute: 'thumb-alignment' },
  } satisfies PropertyDeclarationMap<keyof TimeSliderCore.Props>;

  label = TimeSliderCore.defaultProps.label;
  commitThrottle = TimeSliderCore.defaultProps.commitThrottle;
  step = TimeSliderCore.defaultProps.step;
  largeStep = TimeSliderCore.defaultProps.largeStep;
  orientation = TimeSliderCore.defaultProps.orientation;
  disabled = TimeSliderCore.defaultProps.disabled;
  thumbAlignment = TimeSliderCore.defaultProps.thumbAlignment;

  readonly #core = new TimeSliderCore();
  readonly #provider = new ContextProvider(this, { context: sliderContext });
  readonly #timeState = new PlayerController(this, playerContext, selectTime);
  readonly #bufferState = new PlayerController(this, playerContext, selectBuffer);

  #slider: SliderHandle | null = null;
  #disconnect: AbortController | null = null;

  override connectedCallback(): void {
    super.connectedCallback();

    this.#disconnect = new AbortController();
    const signal = this.#disconnect.signal;

    this.#slider = createSlider({
      getElement: () => this,
      getThumbElement: () => this.querySelector<HTMLElement>('media-slider-thumb'),
      getOrientation: () => this.orientation,
      isRTL: () => isRTL(this),
      isDisabled: () => this.disabled || !this.#timeState.value,
      getPercent: () => {
        const media = this.#timeState.value;
        if (!media) return 0;
        return this.#core.percentFromValue(media.currentTime);
      },
      getStepPercent: () => {
        const { step, min, max } = this.#core.props;
        const range = max - min;
        return range > 0 ? (step / range) * 100 : 0;
      },
      getLargeStepPercent: () => {
        const { largeStep, min, max } = this.#core.props;
        const range = max - min;
        return range > 0 ? (largeStep / range) * 100 : 0;
      },
      onValueChange: () => {
        // Visual update only — CSS vars are refreshed in update().
      },
      onValueCommit: (percent) => {
        this.#seek(percent);
      },
      commitThrottle: this.commitThrottle,
      onDragStart: () => {
        this.dispatchEvent(new CustomEvent('drag-start', { bubbles: true }));
      },
      onDragEnd: () => {
        this.dispatchEvent(new CustomEvent('drag-end', { bubbles: true }));
      },
    });

    this.#slider.interaction.subscribe(() => this.requestUpdate(), { signal });

    // Prevent default touch gestures and text selection during interaction.
    this.style.touchAction = 'none';
    this.style.userSelect = 'none';

    if (__DEV__ && !this.#timeState.value) {
      logMissingFeature(TimeSliderElement.tagName, 'time');
    }
  }

  override disconnectedCallback(): void {
    super.disconnectedCallback();
    this.#slider?.destroy();
    this.#slider = null;
    this.#disconnect?.abort();
    this.#disconnect = null;
  }

  protected override willUpdate(_changed: PropertyValues): void {
    super.willUpdate(_changed);
    this.#core.setProps(this);
  }

  protected override update(_changed: PropertyValues): void {
    super.update(_changed);
    if (!this.#slider) return;

    const time = this.#timeState.value;
    const buffer = this.#bufferState.value;
    if (!time) return;

    const interaction = this.#slider.interaction.current;
    const media = { ...time, ...(buffer ?? { buffered: [], seekable: [] }) };
    const state = this.#core.getTimeState(media, interaction);
    const cssVars = getTimeSliderCSSVars(state);

    applyStyles(this, cssVars);

    // Domain-specific data attributes on root (includes data-seeking).
    applyStateDataAttrs(this, state, TimeSliderDataAttrs);

    // Provide context to child elements with base slider data attrs.
    this.#provider.setValue({
      state,
      pointerValue: this.#core.valueFromPercent(state.pointerPercent),
      thumbAttrs: this.#core.getAttrs(state),
      thumbProps: this.#slider.thumbProps,
      formatValue: (value) => formatTime(value),
    });
  }

  #seek(percent: number): void {
    const media = this.#timeState.value;
    if (!media) return;
    const time = this.#core.valueFromPercent(percent);
    media.seek(time);
  }
}

function formatTime(seconds: number): string {
  const total = Math.round(seconds);
  const minutes = Math.floor(total / 60);
  const secs = total % 60;
  return `${minutes}:${secs.toString().padStart(2, '0')}`;
}