---

import { clamp } from 'lodash-es';

import {
  CustomPriceAxisPaneView,
  CustomPriceAxisView,
  CustomTimeAxisPaneView,
  CustomTimeAxisView,
} from '@core/Drawings/axis';
import {
  clampPointToContainer as clampPointToContainerInElement,
  getAnchorFromPoint,
  getContainerSize as getElementContainerSize,
  getXCoordinateFromTime,
  getYCoordinateFromPrice,
  isPointInBounds,
} from '@core/Drawings/helpers';
import { updateViews } from '@core/Drawings/utils';
import { SeriesDrawingBase } from '@src/core/Drawings/SeriesDrawingBase';

import { getThemeStore } from '@src/theme';
import { t } from '@src/translations';
import { Defaults } from '@src/types/defaults';
import { formatPercent, formatPrice, formatSignedNumber, formatVolume } from '@src/utils';
import { formatDate } from '@src/utils/formatter';

import { DiapsonPaneView } from './paneView';

import {
  createDefaultSettings,
  DiapsonSettings,
  DiapsonStyle,
  DiapsonTextStyle,
  getDiapsonSettingsTabs,
} from './settings';

import type { DrawingHandle } from '@core/Drawings/handles';
import type { Anchor, AxisLabel, AxisSegment, Point } from '@core/Drawings/types';
import type { BaseDrawingParams, ISeriesDrawing } from '@src/core/Drawings/SeriesDrawingBase';
import type { ChartOptionsModel, SettingsTab } from '@src/types';
import type { IPrimitivePaneView, PrimitiveHoveredItem, Time, UTCTimestamp } from 'lightweight-charts';

export type DiapsonRangeMode = 'date' | 'price';

type DiapsonMode = 'idle' | 'drawing' | 'ready' | 'dragging';
type DiapsonHandle = 'body' | 'start' | 'end' | null;
type DiapsonHandleKey = Exclude<DiapsonHandle, 'body' | null>;
type TimeLabelKind = 'left' | 'right';
type PriceLabelKind = 'top' | 'bottom';

interface DiapsonParams extends BaseDrawingParams {
  rangeMode: DiapsonRangeMode;
  stepSize?: number;
  stepLabel?: string;
}

export interface DiapsonState {
  hidden: boolean;
  mode: DiapsonMode;
  rangeMode: DiapsonRangeMode;
  startTime: Time | null;
  endTime: Time | null;
  startPrice: number | null;
  endPrice: number | null;
  settings: DiapsonSettings;
}

interface DiapsonGeometry {
  left: number;
  right: number;
  top: number;
  bottom: number;
  width: number;
  height: number;
  startPoint: Point;
  endPoint: Point;
}

export interface DiapsonRenderData extends DiapsonGeometry, DiapsonStyle, DiapsonTextStyle {
  rangeMode: DiapsonRangeMode;
  showFill: boolean;
  labelLines: string[];
}

interface DateMetrics {
  barsCount: number;
  elapsedText: string;
  volumeText: string;
}

interface PriceMetrics {
  delta: number;
  percent: number;
  steps: number;
}

const BODY_HIT_TOLERANCE = 6;
const MIN_RECTANGLE_WIDTH = 6;
const MIN_RECTANGLE_HEIGHT = 6;

export class Diapson extends SeriesDrawingBase<DiapsonSettings, DiapsonHandleKey> implements ISeriesDrawing {
  private removeSelf?: () => void;
  private openSettings?: () => void;

  protected settings: DiapsonSettings = createDefaultSettings();

  protected mode: DiapsonMode = 'idle';
  private rangeMode: DiapsonRangeMode;

  private startTime: Time | null = null;
  private endTime: Time | null = null;
  private startPrice: number | null = null;
  private endPrice: number | null = null;

  private activeDragTarget: DiapsonHandle = null;
  private dragPointerId: number | null = null;
  private dragStartPoint: Point | null = null;
  private dragGeometrySnapshot: DiapsonGeometry | null = null;

  private displayFormat: ChartOptionsModel = {
    dateFormat: Defaults.dateFormat,
    timeFormat: Defaults.timeFormat,
    showTime: Defaults.showTime,
  };

  private readonly stepSize: number;
  private readonly stepLabel: string;

  private readonly paneView: DiapsonPaneView;
  private readonly timeAxisPaneView: CustomTimeAxisPaneView;
  private readonly priceAxisPaneView: CustomPriceAxisPaneView;
  private readonly leftTimeAxisView: CustomTimeAxisView;
  private readonly rightTimeAxisView: CustomTimeAxisView;
  private readonly topPriceAxisView: CustomPriceAxisView;
  private readonly bottomPriceAxisView: CustomPriceAxisView;

  constructor({
    chart,
    series,
    container,
    interaction,
    rangeMode,
    formatObservable,
    removeSelf,
    openSettings,
    stepSize = 1,
    stepLabel = '',
    initialEvent,
  }: DiapsonParams) {
    super({
      chart,
      series,
      container,
      interaction,
    });

    this.rangeMode = rangeMode;
    this.removeSelf = removeSelf;
    this.openSettings = openSettings;
    this.stepSize = stepSize > 0 ? stepSize : 1;
    this.stepLabel = stepLabel;

    this.paneView = new DiapsonPaneView(this);

    this.timeAxisPaneView = new CustomTimeAxisPaneView({
      getAxisSegments: () => this.getTimeAxisSegments(),
    });

    this.priceAxisPaneView = new CustomPriceAxisPaneView({
      getAxisSegments: () => this.getPriceAxisSegments(),
    });

    this.leftTimeAxisView = new CustomTimeAxisView({
      getAxisLabel: (kind) => this.getTimeAxisLabel(kind),
      labelKind: 'left',
    });

    this.rightTimeAxisView = new CustomTimeAxisView({
      getAxisLabel: (kind) => this.getTimeAxisLabel(kind),
      labelKind: 'right',
    });

    this.topPriceAxisView = new CustomPriceAxisView({
      getAxisLabel: (kind) => this.getPriceAxisLabel(kind),
      labelKind: 'top',
    });

    this.bottomPriceAxisView = new CustomPriceAxisView({
      getAxisLabel: (kind) => this.getPriceAxisLabel(kind),
      labelKind: 'bottom',
    });

    if (formatObservable) {
      this.subscriptions.add(
        formatObservable.subscribe((format) => {
          this.displayFormat = format;
          this.render();
        }),
      );
    }

    this.series.attachPrimitive(this);

    if (initialEvent && initialEvent.sourceEvent) {
      const point = this.getEventPoint(initialEvent.sourceEvent);
      this.startDrawing(point);
    }
  }

  public isCreationPending(): boolean {
    return this.mode === 'idle' || this.mode === 'drawing';
  }

  public setRangeMode(nextMode: DiapsonRangeMode): void {
    if (this.rangeMode === nextMode) {
      return;
    }

    this.rangeMode = nextMode;
    this.resetToIdle();
  }

  public getState(): DiapsonState {
    return {
      hidden: this.hidden,
      mode: this.mode,
      rangeMode: this.rangeMode,
      startTime: this.startTime,
      endTime: this.endTime,
      startPrice: this.startPrice,
      endPrice: this.endPrice,
      settings: { ...this.settings },
    };
  }

  public setState(state: unknown): void {
    if (!state || typeof state !== 'object') {
      return;
    }

    const nextState = state as Partial<DiapsonState>;

    this.hidden = typeof nextState.hidden === 'boolean' ? nextState.hidden : this.hidden;
    this.mode = nextState.mode ?? this.mode;
    this.rangeMode = nextState.rangeMode ?? this.rangeMode;
    this.startTime = 'startTime' in nextState ? (nextState.startTime ?? null) : this.startTime;
    this.endTime = 'endTime' in nextState ? (nextState.endTime ?? null) : this.endTime;
    this.startPrice = 'startPrice' in nextState ? (nextState.startPrice ?? null) : this.startPrice;
    this.endPrice = 'endPrice' in nextState ? (nextState.endPrice ?? null) : this.endPrice;

    if ('settings' in nextState && nextState.settings) {
      this.settings = {
        ...createDefaultSettings(),
        ...nextState.settings,
      };
    }

    this.render();
  }

  public getSettingsTabs(): SettingsTab[] {
    return getDiapsonSettingsTabs(this.settings);
  }

  public updateAllViews(): void {
    updateViews([
      this.paneView,
      this.timeAxisPaneView,
      this.priceAxisPaneView,
      this.leftTimeAxisView,
      this.rightTimeAxisView,
      this.topPriceAxisView,
      this.bottomPriceAxisView,
    ]);
  }

  public paneViews(): readonly IPrimitivePaneView[] {
    return [this.paneView];
  }

  public timeAxisPaneViews(): readonly IPrimitivePaneView[] {
    return [this.timeAxisPaneView];
  }

  public priceAxisPaneViews(): readonly IPrimitivePaneView[] {
    return [this.priceAxisPaneView];
  }

  public timeAxisViews() {
    return [this.leftTimeAxisView, this.rightTimeAxisView];
  }

  public priceAxisViews() {
    return [this.topPriceAxisView, this.bottomPriceAxisView];
  }

  public getRenderData(): DiapsonRenderData | null {
    if (this.hidden) {
      return null;
    }

    const geometry = this.getGeometry();

    if (!geometry) {
      return null;
    }

    return {
      ...geometry,
      rangeMode: this.rangeMode,
      showFill: true,
      labelLines: this.getLabelLines(),
      ...this.settings,
    };
  }

  protected getDrawingHandles(): readonly DrawingHandle<DiapsonHandleKey>[] {
    const geometry = this.getGeometry();

    if (!geometry) {
      return [];
    }

    return [
      {
        id: 'end',
        ...geometry.endPoint,
        shape: 'circle',
        size: 12,
        borderWidth: 2,
      },
      {
        id: 'start',
        ...geometry.startPoint,
        shape: 'circle',
        size: 12,
        borderWidth: 2,
      },
    ];
  }

  protected getTimeAxisSegments(): AxisSegment[] {
    if (!this.isSelected() && !this.isCreationPending()) {
      return [];
    }

    const bounds = this.getTimeBounds();

    if (!bounds) {
      return [];
    }

    const { colors } = getThemeStore();

    return [
      {
        from: bounds.left,
        to: bounds.right,
        color: colors.axisMarkerAreaFill,
      },
    ];
  }

  protected getPriceAxisSegments(): AxisSegment[] {
    if (!this.isSelected() && !this.isCreationPending()) {
      return [];
    }

    const bounds = this.getPriceBounds();

    if (!bounds) {
      return [];
    }

    const { colors } = getThemeStore();

    return [
      {
        from: bounds.top,
        to: bounds.bottom,
        color: colors.axisMarkerAreaFill,
      },
    ];
  }

  protected getTimeAxisLabel(kind: string): AxisLabel | null {
    if ((!this.isSelected() && !this.isCreationPending()) || (kind !== 'left' && kind !== 'right')) {
      return null;
    }

    const labelKind = kind as TimeLabelKind;
    const coordinate = this.getTimeCoordinate(labelKind);
    const text = this.getTimeText(labelKind);

    if (coordinate === null || !text) {
      return null;
    }

    const { colors } = getThemeStore();

    return {
      coordinate,
      text,
      textColor: colors.chartPriceLineText,
      backgroundColor: colors.axisMarkerLabelFill,
    };
  }

  protected getPriceAxisLabel(kind: string): AxisLabel | null {
    if ((!this.isSelected() && !this.isCreationPending()) || (kind !== 'top' && kind !== 'bottom')) {
      return null;
    }

    const labelKind = kind as PriceLabelKind;
    const coordinate = this.getPriceCoordinate(labelKind);
    const text = this.getPriceText(labelKind);

    if (coordinate === null || !text) {
      return null;
    }

    const { colors } = getThemeStore();

    return {
      coordinate,
      text,
      textColor: colors.chartPriceLineText,
      backgroundColor: colors.axisMarkerLabelFill,
    };
  }

  protected getHoveredItem(x: number, y: number): PrimitiveHoveredItem | null {
    if (this.hidden || this.mode === 'idle' || this.mode === 'drawing') {
      return null;
    }

    const point = { x, y };

    if (!this.isSelected()) {
      if (!this.containsPoint(point)) {
        return null;
      }

      return {
        cursorStyle: 'move',
        externalId: `diapson-${this.rangeMode}`,
        zOrder: 'top',
      };
    }

    const handleTarget = this.getDrawingHandleAtPoint(point)?.id ?? null;

    if (handleTarget) {
      return {
        cursorStyle: this.getCursorStyle(handleTarget),
        externalId: `diapson-${this.rangeMode}`,
        zOrder: 'top',
      };
    }

    if (!this.containsPoint(point)) {
      return null;
    }

    return {
      cursorStyle: 'move',
      externalId: `diapson-${this.rangeMode}`,
      zOrder: 'top',
    };
  }

  protected handleDoubleClick = (event: MouseEvent): void => {
    if (this.hidden || this.mode !== 'ready') {
      return;
    }

    const point = this.getEventPoint(event as PointerEvent);

    if (!this.getDrawingHandleAtPoint(point) && !this.containsPoint(point)) {
      return;
    }

    event.preventDefault();
    event.stopPropagation();

    this.openSettings?.();
  };

  protected handlePointerDown = (event: PointerEvent): void => {
    if (this.hidden || event.button !== 0) {
      return;
    }

    const point = this.getEventPoint(event);

    if (this.mode === 'idle') {
      event.preventDefault();
      event.stopPropagation();

      this.startDrawing(point);
      return;
    }

    if (this.mode === 'drawing') {
      event.preventDefault();
      event.stopPropagation();

      this.updateDrawing(point);
      this.finishDrawing();
      return;
    }

    if (this.mode !== 'ready') {
      return;
    }

    if (!this.isSelected()) {
      if (!this.containsPoint(point)) {
        return;
      }

      event.preventDefault();
      event.stopPropagation();

      this.select();
      return;
    }

    const dragTarget = this.getDragTarget(point);

    if (!dragTarget) {
      this.deselect();
      return;
    }

    event.preventDefault();
    event.stopPropagation();

    this.startDragging(point, event.pointerId, dragTarget);
  };

  protected handlePointerMove = (event: PointerEvent): void => {
    const point = this.getEventPoint(event);

    if (this.mode === 'drawing') {
      this.updateDrawing(point);
      return;
    }

    if (this.mode !== 'dragging' || this.dragPointerId !== event.pointerId) {
      return;
    }

    event.preventDefault();

    if (this.activeDragTarget === 'body') {
      this.moveWhole(point);
      this.render();
      return;
    }

    this.resizeRectangle(point);
    this.render();
  };

  protected handlePointerUp = (event: PointerEvent): void => {
    if (this.mode !== 'dragging' || this.dragPointerId !== event.pointerId) {
      return;
    }

    this.finishDragging();
  };

  private startDrawing(point: Point): void {
    const anchor = this.createAnchor(this.clampPointToContainer(point));

    if (!anchor) {
      return;
    }

    this.startTime = anchor.time;
    this.endTime = anchor.time;
    this.startPrice = anchor.price;
    this.endPrice = anchor.price;

    this.mode = 'drawing';
    this.render();
  }

  private updateDrawing(point: Point): void {
    const anchor = this.createAnchor(this.clampPointToContainer(point));

    if (!anchor) {
      return;
    }

    this.endTime = anchor.time;
    this.endPrice = anchor.price;

    this.render();
  }

  private finishDrawing(): void {
    const geometry = this.getGeometry();

    if (!geometry) {
      this.resetToIdle();
      return;
    }

    if (geometry.width < MIN_RECTANGLE_WIDTH || geometry.height < MIN_RECTANGLE_HEIGHT) {
      if (this.removeSelf) {
        this.removeSelf();
        return;
      }

      this.resetToIdle();
      return;
    }

    this.mode = 'ready';
    this.resolveReady?.();

    this.render();
  }

  private startDragging(point: Point, pointerId: number, dragTarget: Exclude<DiapsonHandle, null>): void {
    this.mode = 'dragging';
    this.activeDragTarget = dragTarget;
    this.dragPointerId = pointerId;
    this.dragStartPoint = point;
    this.dragGeometrySnapshot = this.getGeometry();

    this.render();
  }

  private finishDragging(): void {
    this.mode = 'ready';
    this.resolveReady?.();

    this.clearInteractionState();
    this.render();
  }

  private clearInteractionState(): void {
    this.activeDragTarget = null;
    this.dragPointerId = null;
    this.dragStartPoint = null;
    this.dragGeometrySnapshot = null;
  }

  private resetToIdle(): void {
    this.hidden = false;
    this.deselect();
    this.mode = 'idle';
    this.startTime = null;
    this.endTime = null;
    this.startPrice = null;
    this.endPrice = null;
    this.clearInteractionState();
    this.render();
  }

  private getDragTarget(point: Point): Exclude<DiapsonHandle, null> | null {
    return this.getDrawingHandleAtPoint(point)?.id ?? (this.containsPoint(point) ? 'body' : null);
  }

  private moveWhole(point: Point): void {
    const geometry = this.dragGeometrySnapshot;
    const { dragStartPoint } = this;

    if (!geometry || !dragStartPoint) {
      return;
    }

    const { width, height } = this.getContainerSize();

    const rawOffsetX = point.x - dragStartPoint.x;
    const rawOffsetY = point.y - dragStartPoint.y;

    const offsetX = clamp(rawOffsetX, -geometry.left, width - geometry.right);
    const offsetY = clamp(rawOffsetY, -geometry.top, height - geometry.bottom);

    const nextStartPoint = this.clampPointToContainer({
      x: geometry.startPoint.x + offsetX,
      y: geometry.startPoint.y + offsetY,
    });

    const nextEndPoint = this.clampPointToContainer({
      x: geometry.endPoint.x + offsetX,
      y: geometry.endPoint.y + offsetY,
    });

    this.setAnchorsFromPoints(nextStartPoint, nextEndPoint);
  }

  private resizeRectangle(point: Point): void {
    const geometry = this.dragGeometrySnapshot;

    if (!geometry || !this.activeDragTarget || this.activeDragTarget === 'body') {
      return;
    }

    const nextPoint = this.clampPointToContainer(point);

    if (this.activeDragTarget === 'start') {
      this.setAnchorsFromPoints(nextPoint, geometry.endPoint);
      return;
    }

    this.setAnchorsFromPoints(geometry.startPoint, nextPoint);
  }

  private setAnchorsFromPoints(startPoint: Point, endPoint: Point): void {
    const startAnchor = this.createAnchor(startPoint);
    const endAnchor = this.createAnchor(endPoint);

    if (!startAnchor || !endAnchor) {
      return;
    }

    this.startTime = startAnchor.time;
    this.startPrice = startAnchor.price;
    this.endTime = endAnchor.time;
    this.endPrice = endAnchor.price;
  }

  private createAnchor(point: Point): Anchor | null {
    return getAnchorFromPoint(this.chart, this.series, point);
  }

  protected getGeometry(): DiapsonGeometry | null {
    if (this.startTime === null || this.endTime === null || this.startPrice === null || this.endPrice === null) {
      return null;
    }

    const startX = getXCoordinateFromTime(this.chart, this.startTime, this.series);
    const endX = getXCoordinateFromTime(this.chart, this.endTime, this.series);
    const startY = getYCoordinateFromPrice(this.series, this.startPrice);
    const endY = getYCoordinateFromPrice(this.series, this.endPrice);

    if (startX === null || endX === null || startY === null || endY === null) {
      return null;
    }

    const { width, height } = this.getContainerSize();

    const startPoint = {
      x: clamp(Math.round(Number(startX)), 0, width),
      y: clamp(Math.round(Number(startY)), 0, height),
    };

    const endPoint = {
      x: clamp(Math.round(Number(endX)), 0, width),
      y: clamp(Math.round(Number(endY)), 0, height),
    };

    const left = Math.round(Math.min(startPoint.x, endPoint.x));
    const right = Math.round(Math.max(startPoint.x, endPoint.x));
    const top = Math.round(Math.min(startPoint.y, endPoint.y));
    const bottom = Math.round(Math.max(startPoint.y, endPoint.y));

    return {
      left,
      right,
      top,
      bottom,
      width: right - left,
      height: bottom - top,
      startPoint,
      endPoint,
    };
  }

  private getLabelLines(): string[] {
    if (this.rangeMode === 'date') {
      const metrics = this.getDateMetrics();

      if (!metrics) {
        return [];
      }

      const firstLine = metrics.elapsedText
        ? `${metrics.barsCount} ${t('bars')}, ${metrics.elapsedText}`
        : `${metrics.barsCount} ${t('bars')}`;

      if (!metrics.volumeText) {
        return [firstLine];
      }

      return [firstLine, `${t('Vol')} ${metrics.volumeText}`];
    }

    const metrics = this.getPriceMetrics();

    if (!metrics) {
      return [];
    }

    const percentText =
      metrics.percent < 0 ? `-${formatPercent(Math.abs(metrics.percent))}` : formatPercent(Math.abs(metrics.percent));

    const absSteps = Math.abs(metrics.steps);
    let stepsText = '';

    if (Number.isInteger(absSteps)) {
      stepsText = absSteps.toString();
    } else if (absSteps >= 1000) {
      stepsText = absSteps.toFixed(0);
    } else if (absSteps >= 100) {
      stepsText = absSteps.toFixed(1);
    } else {
      stepsText = absSteps.toFixed(2);
    }

    if (metrics.steps < 0) {
      stepsText = `-${stepsText}`;
    }

    const stepSuffix = this.stepLabel ? ` ${this.stepLabel}` : '';

    return [`${formatSignedNumber(metrics.delta)} (${percentText}) ${stepsText}${stepSuffix}`];
  }

  private getDateMetrics(): DateMetrics | null {
    const leftTime = this.getLeftTimeValue();
    const rightTime = this.getRightTimeValue();

    if (!leftTime || !rightTime) {
      return null;
    }

    const barsCount = this.getBarsCount();
    const durationSeconds = Math.max(0, Math.floor(Math.abs(Number(rightTime) - Number(leftTime))));
    const days = Math.floor(durationSeconds / 86400);
    const hours = Math.floor((durationSeconds % 86400) / 3600);
    const minutes = Math.floor((durationSeconds % 3600) / 60);
    const seconds = durationSeconds % 60;

    const elapsedParts: string[] = [];

    if (days > 0) {
      elapsedParts.push(`${days}d`);
    }

    if (hours > 0) {
      elapsedParts.push(`${hours}h`);
    }

    if (minutes > 0) {
      elapsedParts.push(`${minutes}m`);
    }

    if (elapsedParts.length === 0) {
      elapsedParts.push(`${seconds}s`);
    }

    const volume = this.getVolumeInRange();

    return {
      barsCount,
      elapsedText: elapsedParts.slice(0, 2).join(' '),
      volumeText: volume > 0 ? formatVolume(volume) : '',
    };
  }

  private getPriceMetrics(): PriceMetrics | null {
    if (this.startPrice === null || this.endPrice === null) {
      return null;
    }

    const delta = this.endPrice - this.startPrice;

    return {
      delta,
      percent: this.startPrice !== 0 ? (delta / Math.abs(this.startPrice)) * 100 : 0,
      steps: delta / this.stepSize,
    };
  }

  private getBarsCount(): number {
    if (this.startTime === null || this.endTime === null) {
      return 0;
    }

    const startIndex = this.findIndexByTime(this.startTime);
    const endIndex = this.findIndexByTime(this.endTime);

    if (startIndex < 0 || endIndex < 0) {
      return 0;
    }

    return Math.abs(endIndex - startIndex);
  }

  private getVolumeInRange(): number {
    if (this.startTime === null || this.endTime === null) {
      return 0;
    }

    const data = this.series.data() ?? [];

    if (!data.length) {
      return 0;
    }

    const startIndex = this.findIndexByTime(this.startTime);
    const endIndex = this.findIndexByTime(this.endTime);

    if (startIndex < 0 || endIndex < 0) {
      return 0;
    }

    const from = Math.min(startIndex, endIndex);
    const to = Math.max(startIndex, endIndex);

    let volume = 0;

    for (let index = from; index <= to; index += 1) {
      const item = data[index] as unknown as Record<string, unknown> | undefined;

      if (!item) {
        continue;
      }

      if (typeof item.volume === 'number') {
        volume += item.volume;
        continue;
      }

      const customValues = item.customValues as Record<string, unknown> | undefined;

      if (customValues && typeof customValues.volume === 'number') {
        volume += customValues.volume;
      }
    }

    return volume;
  }

  private findIndexByTime(time: Time): number {
    const data = this.series.data() ?? [];

    return data.findIndex((item) => Number(item.time) === Number(time));
  }

  private getTimeBounds(): { left: number; right: number } | null {
    const geometry = this.getGeometry();

    if (!geometry) {
      return null;
    }

    return {
      left: geometry.left,
      right: geometry.right,
    };
  }

  private getPriceBounds(): { top: number; bottom: number } | null {
    const geometry = this.getGeometry();

    if (!geometry) {
      return null;
    }

    return {
      top: geometry.top,
      bottom: geometry.bottom,
    };
  }

  private getTimeCoordinate(kind: TimeLabelKind): number | null {
    const geometry = this.getGeometry();

    if (!geometry) {
      return null;
    }

    return kind === 'left' ? geometry.left : geometry.right;
  }

  private getPriceCoordinate(kind: PriceLabelKind): number | null {
    const geometry = this.getGeometry();

    if (!geometry) {
      return null;
    }

    return kind === 'top' ? geometry.top : geometry.bottom;
  }

  private getTimeText(kind: TimeLabelKind): string {
    const time = kind === 'left' ? this.getLeftTimeValue() : this.getRightTimeValue();

    if (!time) {
      return '';
    }

    return formatDate(
      time as UTCTimestamp,
      this.displayFormat.dateFormat,
      this.displayFormat.timeFormat,
      this.displayFormat.showTime,
    );
  }

  private getPriceText(kind: PriceLabelKind): string {
    const price = kind === 'top' ? this.getTopPriceValue() : this.getBottomPriceValue();

    if (price === null) {
      return '';
    }

    return formatPrice(price) ?? '';
  }

  private getLeftTimeValue(): Time | null {
    if (this.startTime === null || this.endTime === null) {
      return null;
    }

    const startX = getXCoordinateFromTime(this.chart, this.startTime, this.series);
    const endX = getXCoordinateFromTime(this.chart, this.endTime, this.series);

    if (startX === null || endX === null) {
      return this.startTime;
    }

    return Number(startX) <= Number(endX) ? this.startTime : this.endTime;
  }

  private getRightTimeValue(): Time | null {
    if (this.startTime === null || this.endTime === null) {
      return null;
    }

    const startX = getXCoordinateFromTime(this.chart, this.startTime, this.series);
    const endX = getXCoordinateFromTime(this.chart, this.endTime, this.series);

    if (startX === null || endX === null) {
      return this.endTime;
    }

    return Number(startX) <= Number(endX) ? this.endTime : this.startTime;
  }

  private getTopPriceValue(): number | null {
    if (this.startPrice === null || this.endPrice === null) {
      return null;
    }

    const startY = getYCoordinateFromPrice(this.series, this.startPrice);
    const endY = getYCoordinateFromPrice(this.series, this.endPrice);

    if (startY === null || endY === null) {
      return Math.max(this.startPrice, this.endPrice);
    }

    return Number(startY) <= Number(endY) ? this.startPrice : this.endPrice;
  }

  private getBottomPriceValue(): number | null {
    if (this.startPrice === null || this.endPrice === null) {
      return null;
    }

    const startY = getYCoordinateFromPrice(this.series, this.startPrice);
    const endY = getYCoordinateFromPrice(this.series, this.endPrice);

    if (startY === null || endY === null) {
      return Math.min(this.startPrice, this.endPrice);
    }

    return Number(startY) <= Number(endY) ? this.endPrice : this.startPrice;
  }

  private containsPoint(point: Point): boolean {
    const geometry = this.getGeometry();

    if (!geometry) {
      return false;
    }

    return isPointInBounds(point, geometry, BODY_HIT_TOLERANCE);
  }

  private getCursorStyle(handle: Exclude<DiapsonHandle, null>): PrimitiveHoveredItem['cursorStyle'] {
    if (handle === 'body') {
      return 'move';
    }

    const geometry = this.getGeometry();

    if (!geometry) {
      return 'default';
    }

    const sameDirection =
      (geometry.endPoint.x - geometry.startPoint.x >= 0 && geometry.endPoint.y - geometry.startPoint.y >= 0) ||
      (geometry.endPoint.x - geometry.startPoint.x < 0 && geometry.endPoint.y - geometry.startPoint.y < 0);

    return sameDirection ? 'nwse-resize' : 'nesw-resize';
  }

  private getContainerSize(): { width: number; height: number } {
    return getElementContainerSize(this.container);
  }

  private clampPointToContainer(point: Point): Point {
    return clampPointToContainerInElement(point, this.container);
  }
}


import { CanvasRenderingTarget2D } from 'fancy-canvas';
import { IPrimitivePaneRenderer } from 'lightweight-charts';

import { Diapson, DiapsonRenderData } from './diapson';

import type { DiapsonTextStyle } from './settings';

const UI = {
  lineWidth: 1,
  labelPadding: 4,
  labelRadius: 2,
  labelBottomOffset: 8,
  arrowSize: 7,
  lineHeightMultiplier: 1.2,
};

export class DiapsonPaneRenderer implements IPrimitivePaneRenderer {
  private readonly diapson: Diapson;

  constructor(diapson: Diapson) {
    this.diapson = diapson;
  }

  public draw(target: CanvasRenderingTarget2D): void {
    const data = this.diapson.getRenderData();

    if (!data) {
      return;
    }

    target.useBitmapCoordinateSpace(({ context, horizontalPixelRatio, verticalPixelRatio }) => {
      const left = data.left * horizontalPixelRatio;
      const right = data.right * horizontalPixelRatio;
      const top = data.top * verticalPixelRatio;
      const bottom = data.bottom * verticalPixelRatio;
      const width = Math.max(right - left, 0);
      const height = Math.max(bottom - top, 0);
      const pixelRatio = Math.max(horizontalPixelRatio, verticalPixelRatio);
      const lineWidth = UI.lineWidth * pixelRatio;
      const arrowSize = UI.arrowSize * pixelRatio;

      context.save();

      if (data.showFill) {
        context.fillStyle = data.fillColor;
        context.fillRect(left, top, width, height);
      }

      context.strokeStyle = data.borderColor;
      context.lineWidth = lineWidth;

      if (data.rangeMode === 'date') {
        drawVerticalBoundary(context, left, top, bottom);
        drawVerticalBoundary(context, right, top, bottom);

        drawHorizontalArrow(
          context,
          left,
          right,
          (top + bottom) / 2,
          arrowSize,
          data.startPoint.x <= data.endPoint.x ? 'right' : 'left',
        );
      } else {
        drawHorizontalBoundary(context, top, left, right);
        drawHorizontalBoundary(context, bottom, left, right);

        drawVerticalArrow(
          context,
          (left + right) / 2,
          top,
          bottom,
          arrowSize,
          data.startPoint.y <= data.endPoint.y ? 'down' : 'up',
        );
      }

      if (data.labelLines.length > 0) {
        drawLabel(context, data, horizontalPixelRatio, verticalPixelRatio, data);
      }

      context.restore();
    });
  }
}

function drawVerticalBoundary(context: CanvasRenderingContext2D, x: number, top: number, bottom: number): void {
  context.beginPath();
  context.moveTo(x, top);
  context.lineTo(x, bottom);
  context.stroke();
}

function drawHorizontalBoundary(context: CanvasRenderingContext2D, y: number, left: number, right: number): void {
  context.beginPath();
  context.moveTo(left, y);
  context.lineTo(right, y);
  context.stroke();
}

function drawHorizontalArrow(
  context: CanvasRenderingContext2D,
  left: number,
  right: number,
  y: number,
  arrowSize: number,
  direction: 'left' | 'right',
): void {
  context.beginPath();
  context.moveTo(left, y);
  context.lineTo(right, y);
  context.stroke();

  if (direction === 'right') {
    context.beginPath();
    context.moveTo(right, y);
    context.lineTo(right - arrowSize, y - arrowSize);
    context.moveTo(right, y);
    context.lineTo(right - arrowSize, y + arrowSize);
    context.stroke();

    return;
  }

  context.beginPath();
  context.moveTo(left, y);
  context.lineTo(left + arrowSize, y - arrowSize);
  context.moveTo(left, y);
  context.lineTo(left + arrowSize, y + arrowSize);
  context.stroke();
}

function drawVerticalArrow(
  context: CanvasRenderingContext2D,
  x: number,
  top: number,
  bottom: number,
  arrowSize: number,
  direction: 'up' | 'down',
): void {
  context.beginPath();
  context.moveTo(x, top);
  context.lineTo(x, bottom);
  context.stroke();

  if (direction === 'down') {
    context.beginPath();
    context.moveTo(x, bottom);
    context.lineTo(x - arrowSize, bottom - arrowSize);
    context.moveTo(x, bottom);
    context.lineTo(x + arrowSize, bottom - arrowSize);
    context.stroke();

    return;
  }

  context.beginPath();
  context.moveTo(x, top);
  context.lineTo(x - arrowSize, top + arrowSize);
  context.moveTo(x, top);
  context.lineTo(x + arrowSize, top + arrowSize);
  context.stroke();
}

function drawLabel(
  context: CanvasRenderingContext2D,
  data: DiapsonRenderData,
  horizontalPixelRatio: number,
  verticalPixelRatio: number,
  textStyle: DiapsonTextStyle,
): void {
  const pixelRatio = Math.max(horizontalPixelRatio, verticalPixelRatio);
  const fontSize = textStyle.fontSize * pixelRatio;
  const padding = UI.labelPadding * pixelRatio;
  const lineHeight = Math.round(textStyle.fontSize * UI.lineHeightMultiplier) * verticalPixelRatio;
  const radius = UI.labelRadius * pixelRatio;
  const bottomOffset = UI.labelBottomOffset * verticalPixelRatio;

  const paneLeft = data.left * horizontalPixelRatio;
  const paneRight = data.right * horizontalPixelRatio;
  const paneBottom = data.bottom * verticalPixelRatio;

  context.save();
  context.font = getLabelFont(textStyle, fontSize);

  const maxTextWidth = data.labelLines.reduce((maxWidth, line) => {
    return Math.max(maxWidth, context.measureText(line).width);
  }, 0);

  const labelWidth = maxTextWidth + padding * 2;
  const labelHeight = data.labelLines.length * lineHeight + padding * 2;
  const rangeCenterX = (paneLeft + paneRight) / 2;
  const maxLeft = Math.max(4, context.canvas.width - labelWidth - 4);
  const maxTop = Math.max(4, context.canvas.height - labelHeight - 4);

  const boxLeft = clampNumber(rangeCenterX - labelWidth / 2, 4, maxLeft);
  const boxTop = clampNumber(paneBottom + bottomOffset, 4, maxTop);

  context.fillStyle = textStyle.labelBackgroundColor;
  fillRoundedRect(context, boxLeft, boxTop, labelWidth, labelHeight, radius);

  context.fillStyle = textStyle.labelTextColor;
  context.textAlign = 'center';
  context.textBaseline = 'middle';

  data.labelLines.forEach((line, index) => {
    const lineY = boxTop + padding + lineHeight * index + lineHeight / 2;
    context.fillText(line, boxLeft + labelWidth / 2, lineY);
  });

  context.restore();
}

function getLabelFont(style: DiapsonTextStyle, fontSize: number): string {
  const italic = style.isItalic ? 'italic ' : '';
  const bold = style.isBold ? '700 ' : '';

  return `${italic}${bold}${fontSize}px Inter, sans-serif`;
}

function fillRoundedRect(
  context: CanvasRenderingContext2D,
  x: number,
  y: number,
  width: number,
  height: number,
  radius: number,
): void {
  context.beginPath();
  context.moveTo(x + radius, y);
  context.lineTo(x + width - radius, y);
  context.quadraticCurveTo(x + width, y, x + width, y + radius);
  context.lineTo(x + width, y + height - radius);
  context.quadraticCurveTo(x + width, y + height, x + width - radius, y + height);
  context.lineTo(x + radius, y + height);
  context.quadraticCurveTo(x, y + height, x, y + height - radius);
  context.lineTo(x, y + radius);
  context.quadraticCurveTo(x, y, x + radius, y);
  context.closePath();
  context.fill();
}

function clampNumber(value: number, min: number, max: number): number {
  if (max < min) {
    return min;
  }

  return Math.max(min, Math.min(value, max));
}