/** @jsxImportSource react */

import { Axis, AxisConfig, AxisInstance } from "./Axis";
import { VDOM } from "../../ui/Widget";
import { Stack } from "./Stack";
import { Format } from "../../ui/Format";
import { isNumber } from "../../util/isNumber";
import { zeroTime } from "../../util/date/zeroTime";
import { Console } from "../../util/Console";
import { parseDateInvariant } from "../../util";
import { RenderingContext } from "../../ui/RenderingContext";
import { NumberProp, Prop, StringProp } from "../../ui/Prop";

export interface TimeAxisConfig extends AxisConfig {
  /** Minimum value. */
  min?: Prop<number | string | Date | null>;

  /** Maximum value. */
  max?: Prop<number | string | Date | null>;

  /** Base CSS class to be applied to the element. Defaults to `timeaxis`. */
  baseClass?: string;

  /** A number ranged between `0-2`. `0` means that the range is aligned with the lowest ticks. Default value is `1`, which means that the range is aligned with medium ticks. Use value `2` to align with major ticks. */
  snapToTicks?: 0 | 1 | 2 | false;

  tickDivisions?: Record<string, number[][]>;
  minTickUnit?: string;

  /** Set to true to apply precise label distances from minLabelDistanceFormatOverride based on the resolved label format. */
  useLabelDistanceFormatOverrides?: boolean;

  /** Mapping of formats to label distances, i.e. { "datetime;YYYYMM": 80 } */
  minLabelDistanceFormatOverride?: Record<string, number>;
  minLabelDistanceFormatOverrideDefaults?: Record<string, number>;

  /** Axis labels format string override. */
  format?: StringProp;

  /** Custom date decoder function. */
  decode?: (date: string) => string;

  /** Size of a zone reserved for labels for both lower and upper end of the axis. */
  deadZone?: number;

  /** Size of a zone reserved for labels near the lower end of the axis. */
  lowerDeadZone?: number;

  /** Size of a zone reserved for labels near the upper (higher) end of the axis. */
  upperDeadZone?: number;
}

Format.registerFactory("yearOrMonth", (format: string) => {
  let year = Format.parse("datetime;yyyy");
  let month = Format.parse("datetime;MMM");
  return function (date: any): string {
    let d = parseDateInvariant(date);
    if (d.getMonth() == 0) return year(d);
    else return month(d);
  };
});

Format.registerFactory("monthOrDay", (format: string) => {
  let month = Format.parse("datetime;MMM");
  let day = Format.parse("datetime;dd");
  return function (date: any): string {
    let d = parseDateInvariant(date);
    if (d.getDate() == 1) return month(d);
    else return day(d);
  };
});

export class TimeAxis extends Axis {
  declare deadZone: number;
  declare lowerDeadZone: number;
  declare upperDeadZone: number;
  declare snapToTicks: number | false;
  declare tickDivisions: Record<string, number[][]>;
  declare minTickUnit: string;
  declare useLabelDistanceFormatOverrides: boolean;
  declare minLabelDistanceFormatOverride: Record<string, number>;
  declare minLabelDistanceFormatOverrideDefaults: Record<string, number>;
  declare format: string;
  declare decode: TimeAxisConfig["decode"];

  constructor(config: TimeAxisConfig) {
    super(config);
  }

  init(): void {
    if (this.labelAnchor == "auto")
      this.labelAnchor = this.vertical
        ? this.secondary
          ? "start"
          : "end"
        : "start";

    if (this.labelDx == "auto") this.labelDx = this.vertical ? 0 : "5px";

    if (this.deadZone) {
      this.lowerDeadZone = this.deadZone;
      this.upperDeadZone = this.deadZone;
    }

    this.minLabelDistanceFormatOverride = {
      ...this.minLabelDistanceFormatOverrideDefaults,
      ...this.minLabelDistanceFormatOverride,
    };

    super.init();
  }

  declareData(...args: any[]): void {
    super.declareData(
      {
        anchors: undefined,
        min: undefined,
        max: undefined,
        inverted: undefined,
        lowerDeadZone: undefined,
        upperDeadZone: undefined,
      },
      ...args,
    );
  }

  initInstance(context: RenderingContext, instance: AxisInstance): void {
    instance.calculator = new TimeScale();
  }

  explore(context: RenderingContext, instance: AxisInstance): void {
    super.explore(context, instance);
    let { min, max, normalized, inverted, lowerDeadZone, upperDeadZone } =
      instance.data;
    instance.calculator.reset(
      min,
      max,
      this.snapToTicks,
      this.tickDivisions,
      Math.max(1, this.minTickDistance),
      Math.max(1, this.minLabelDistance),
      normalized,
      inverted,
      this.minTickUnit,
      lowerDeadZone,
      upperDeadZone,
      this.decode,
      this.useLabelDistanceFormatOverrides
        ? this.minLabelDistanceFormatOverride
        : {},
      this.format,
    );
  }

  render(
    context: RenderingContext,
    instance: AxisInstance,
    key: string,
  ): React.ReactNode {
    let { data, cached, calculator } = instance;

    cached.axis = calculator.hash();

    if (!data.bounds.valid()) return null;

    let format = calculator.resolvedFormat;
    let minLabelDistance = calculator.resolvedMinLabelDistance;
    let formatter = Format.parse(format);

    return (
      <g key={key} className={data.classNames} style={data.style}>
        {this.renderTicksAndLabels(
          context,
          instance,
          formatter,
          minLabelDistance,
        )}
      </g>
    );
  }
}

Axis.alias("time", TimeAxis);

TimeAxis.prototype.baseClass = "timeaxis";
TimeAxis.prototype.tickDivisions = {
  second: [[1, 5, 15, 30]],
  minute: [[1, 5, 15, 30]],
  hour: [
    [1, 2, 4, 8],
    [1, 3, 6, 12],
  ],
  day: [[1]],
  week: [[1]],
  month: [[1, 3, 6]],
  year: [
    [1, 2, 10],
    [1, 5, 10],
    [5, 10, 50],
    [10, 50, 100],
  ],
};

const TimeFormats = {
  fullDateAndTime: "datetime;yyyy MMM dd HH mm ss n",
  shortMonthDate: "datetime;yyyy MMM dd",
};

TimeAxis.prototype.snapToTicks = 0;
TimeAxis.prototype.tickSize = 15;
TimeAxis.prototype.minLabelDistance = 60;
TimeAxis.prototype.minTickDistance = 60;
TimeAxis.prototype.minTickUnit = "second";
TimeAxis.prototype.useLabelDistanceFormatOverrides = false;
TimeAxis.prototype.minLabelDistanceFormatOverrideDefaults = {
  [TimeFormats.fullDateAndTime]: 150,
  [TimeFormats.shortMonthDate]: 90,
};

function monthNumber(date: Date): number {
  return date.getFullYear() * 12 + date.getMonth() + (date.getDate() - 1) / 31;
}

function yearNumber(date: Date): number {
  return monthNumber(date) / 12;
}

const milliSeconds: Record<string, number> = {
  second: 1000,
  minute: 60 * 1000,
  hour: 3600 * 1000,
  day: 3600 * 24 * 1000,
  week: 3600 * 24 * 7 * 1000,
  month: 3600 * 24 * 30 * 1000,
  year: 3600 * 24 * 365 * 1000,
};

interface TickSize {
  size: number;
  measure: string;
  noLabels?: boolean;
}

interface TimeScaleRange {
  factor: number;
  min: number;
  max: number;
  minPadding: number;
  maxPadding: number;
}

class TimeScale {
  dateCache: Record<string, number>;
  min: number | null;
  max: number | null;
  snapToTicks: number | false;
  tickDivisions: Record<string, number[][]>;
  minLabelDistance: number;
  minTickDistance: number;
  tickSizes: TickSize[];
  normalized: boolean;
  minTickUnit: string;
  inverted: boolean;
  lowerDeadZone: number;
  upperDeadZone: number;
  minValue?: number;
  maxValue?: number;
  minValuePadded?: number;
  maxValuePadded?: number;
  stacks: Record<string, Stack>;
  decode?: (date: string) => string;
  minLabelDistanceFormatOverride: Record<string, number>;
  format: string;
  origin: number;
  scale: TimeScaleRange;
  a: number;
  b: number;
  tickMeasure: string;
  resolvedFormat: string | null;
  resolvedMinLabelDistance: number;
  shouldUpdate: boolean;

  reset(
    min: any,
    max: any,
    snapToTicks: number | false,
    tickDivisions: Record<string, number[][]>,
    minTickDistance: number,
    minLabelDistance: number,
    normalized: boolean,
    inverted: boolean,
    minTickUnit: string,
    lowerDeadZone: number,
    upperDeadZone: number,
    decode: ((date: string) => string) | undefined,
    minLabelDistanceFormatOverride: Record<string, number>,
    format: string,
  ): void {
    this.dateCache = {};
    this.min = min != null ? this.decodeValue(min) : null;
    this.max = max != null ? this.decodeValue(max) : null;
    this.snapToTicks = snapToTicks;
    this.tickDivisions = tickDivisions;
    this.minLabelDistance = minLabelDistance;
    this.minTickDistance = minTickDistance;
    this.tickSizes = [];
    this.normalized = normalized;
    this.minTickUnit = minTickUnit;
    this.inverted = inverted;
    this.lowerDeadZone = lowerDeadZone || 0;
    this.upperDeadZone = upperDeadZone || 0;
    this.minValue = undefined;
    this.maxValue = undefined;
    this.minValuePadded = undefined;
    this.maxValuePadded = undefined;
    this.stacks = {};
    this.decode = decode;
    this.minLabelDistanceFormatOverride = minLabelDistanceFormatOverride;
    this.format = format;
  }

  decodeValue(date: any): number {
    if (date instanceof Date) return date.getTime();

    switch (typeof date) {
      case "string":
        let v = this.dateCache[date];
        if (!v) {
          if (this.decode) date = this.decode(date);
          v = this.dateCache[date] = parseDateInvariant(date).getTime();
        }
        return v;

      case "number":
        return parseDateInvariant(date).getTime();
    }
    return 0;
  }

  encodeValue(v: number): string {
    return new Date(v).toISOString();
  }

  getFormat(unit: string, scale: TimeScaleRange): string {
    switch (unit) {
      case "year":
        return "datetime;yyyy";

      case "month":
        if (
          new Date(scale.min).getFullYear() != new Date(scale.max).getFullYear()
        )
          return "yearOrMonth";
        return "datetime;yyyy MMM";

      case "week":
        return "datetime;MMMdd";

      case "day":
        if (
          new Date(scale.min).getFullYear() !=
            new Date(scale.max).getFullYear() ||
          new Date(scale.min).getMonth() != new Date(scale.max).getMonth()
        )
          return "monthOrDay";

        return TimeFormats.shortMonthDate;

      case "hour":
        return "datetime;HH mm n";

      case "minute":
        return "datetime;HH mm n";

      case "second":
        return "datetime;mm ss";

      default:
        return TimeFormats.fullDateAndTime;
    }
  }

  map(v: any, offset: number = 0): number {
    return (
      this.origin +
      (this.decodeValue(v) + offset - this.scale.min + this.scale.minPadding) *
        this.scale.factor
    );
  }

  constrainValue(v: number): number {
    return Math.max(this.scale.min, Math.min(this.scale.max, v));
  }

  trackValue(
    v: number,
    offset: number = 0,
    constrain: boolean = false,
  ): number {
    let value =
      (v - this.origin) / this.scale.factor -
      offset +
      this.scale.min -
      this.scale.minPadding;
    if (constrain) value = this.constrainValue(value);
    return value;
  }

  hash(): Record<string, any> {
    let r: any = {
      origin: this.origin,
      factor: this.scale.factor,
      min: this.scale.min,
      max: this.scale.max,
      minPadding: this.scale.minPadding,
      maxPadding: this.scale.maxPadding,
    };
    r.stacks = Object.keys(this.stacks)
      .map((s) => this.stacks[s].info?.join(","))
      .join(":");
    return r;
  }

  isSame(x: any): boolean {
    let hash = this.hash();
    let same = x && !Object.keys(hash).some((k) => x[k] !== hash[k]);
    this.shouldUpdate = !same;
    return same;
  }

  measure(a: number, b: number): void {
    this.a = a;
    this.b = b;

    for (let s in this.stacks) {
      let info = this.stacks[s].measure(this.normalized);
      let [min, max] = info;
      if (this.minValue == null || min < this.minValue) this.minValue = min;
      if (this.max == null || max > this.maxValue!) this.maxValue = max;
      this.stacks[s].info = info;
    }

    if (this.min == null) {
      if (this.minValue != null) this.min = this.minValue;
      else this.min = 0;
    }

    if (this.max == null) {
      if (this.maxValue != null) this.max = this.maxValue;
      else this.max = this.normalized ? 1 : 100;
    }

    this.origin = this.inverted ? this.b : this.a;

    this.calculateTicks();
    if (this.scale == null) {
      this.scale = this.getScale();
    }
  }

  getTimezoneOffset(date: Date): number {
    return date.getTimezoneOffset() * 60 * 1000;
  }

  getScale(
    tickSize?: number | null,
    measure?: string,
    minRange: number = 1000,
  ): TimeScaleRange {
    let { min, max, upperDeadZone, lowerDeadZone } = this;

    let smin: number = min!;
    let smax: number = max!;

    if (tickSize) {
      let minDate = new Date(min!);
      let maxDate = new Date(max!);

      switch (measure) {
        case "second":
        case "minute":
        case "hour":
        case "day":
        default:
          let minOffset = this.getTimezoneOffset(minDate);
          let maxOffset = this.getTimezoneOffset(maxDate);
          let mondayOffset = 4 * milliSeconds.day; //new Date(0).getDay() => 4
          smin =
            Math.floor((smin - minOffset - mondayOffset) / tickSize) *
              tickSize +
            minOffset +
            mondayOffset;
          smax =
            Math.ceil((smax - maxOffset - mondayOffset) / tickSize) * tickSize +
            maxOffset +
            mondayOffset;
          break;

        case "month":
          tickSize /= milliSeconds.month;
          let minMonth = monthNumber(minDate);
          let maxMonth = monthNumber(maxDate);
          minMonth = Math.floor(minMonth / tickSize) * tickSize;
          maxMonth = Math.ceil(maxMonth / tickSize) * tickSize;
          smin = new Date(
            Math.floor(minMonth / 12),
            minMonth % 12,
            1,
          ).getTime();
          smax = new Date(
            Math.floor(maxMonth / 12),
            maxMonth % 12,
            1,
          ).getTime();
          break;

        case "year":
          tickSize /= milliSeconds.year;
          let minYear = yearNumber(minDate);
          let maxYear = yearNumber(maxDate);
          minYear = Math.floor(minYear / tickSize) * tickSize;
          maxYear = Math.ceil(maxYear / tickSize) * tickSize;
          smin = new Date(minYear, 0, 1).getTime();
          smax = new Date(maxYear, 0, 1).getTime();
          break;
      }
    } else {
      if (this.minValue == min) smin = this.minValuePadded!;
      if (this.maxValue == max) smax = this.maxValuePadded!;
    }

    if (smax - smin < minRange) {
      let delta = (minRange - (smax - smin)) / 2;
      smin -= delta;
      smax += delta;
    }

    //padding should be activated only if using min/max obtained from the data
    let minPadding =
      this.minValue === min ? Math.max(0, smin - this.minValuePadded!) : 0;
    let maxPadding =
      this.maxValue === max ? Math.max(0, this.maxValuePadded! - smax) : 0;

    let factor =
      smin < smax
        ? Math.abs(this.b - this.a) / (smax - smin + minPadding + maxPadding)
        : 0;
    if (factor > 0 && (upperDeadZone > 0 || lowerDeadZone > 0)) {
      smin -= lowerDeadZone / factor;
      smax += upperDeadZone / factor;
      minPadding =
        this.minValuePadded != null
          ? Math.max(0, smin - this.minValuePadded)
          : 0;
      maxPadding =
        this.maxValuePadded != null
          ? Math.max(0, this.maxValuePadded - smax)
          : 0;
      factor =
        smin < smax
          ? Math.abs(this.b - this.a) / (smax - smin + minPadding + maxPadding)
          : 0;
    }

    let sign = this.b > this.a ? 1 : -1;

    return {
      factor: sign * (this.inverted ? -factor : factor),
      min: smin,
      max: smax,
      minPadding,
      maxPadding,
    };
  }

  acknowledge(value: any, width: number = 0, offset: number = 0): void {
    value = this.decodeValue(value);
    if (
      this.minValue == null ||
      value + offset - width / 2 < this.minValuePadded!
    ) {
      this.minValue = value;
      this.minValuePadded = value + offset - width / 2;
    }
    if (
      this.maxValue == null ||
      value + offset + width / 2 > this.maxValuePadded!
    ) {
      this.maxValue = value;
      this.maxValuePadded = value + offset + width / 2;
    }
  }

  getStack(name: string): Stack {
    let s = this.stacks[name];
    if (!s) s = this.stacks[name] = new Stack();
    return s;
  }

  stacknowledge(name: string, ordinal: string, value: number | null): void {
    return this.getStack(name).acknowledge(ordinal, value);
  }

  stack(name: string, ordinal: string, value: number | null): number | null {
    let v = this.getStack(name).stack(ordinal, value);
    return v != null ? this.map(v) : null;
  }

  findTickSize(minPxDist: number): TickSize | undefined {
    return this.tickSizes.find(
      ({ size, noLabels }) =>
        !noLabels && size * Math.abs(this.scale.factor) >= minPxDist,
    );
  }

  getTickSizes(): TickSize[] {
    return this.tickSizes;
  }

  calculateTicks(): void {
    let minReached = false;

    let minRange = 1000;

    for (let unit in milliSeconds) {
      if (!minReached) {
        if (unit == this.minTickUnit) minReached = true;
        else continue;
      }

      let unitSize = milliSeconds[unit];
      let divisions = this.tickDivisions[unit];

      if (this.tickSizes.length > 0) {
        //add ticks from higher levels
        this.tickSizes.push(
          ...divisions[0].map((s) => ({ size: s * unitSize, measure: unit })),
        );
        break;
      }

      let bestLabelDistance = Infinity;
      let bestMinLabelDistance = this.minLabelDistance;
      let bestTicks: number[] = [];
      let bestScale: TimeScaleRange | null = null;
      let bestFormat: string | null = null;

      this.tickMeasure = unit;

      for (let i = 0; i < divisions.length; i++) {
        let divs = divisions[i];
        for (let d = 0; d < divs.length; d++) {
          //if (useSnapToTicks && d < Math.min(divs.length - 1, this.snapToTicks)) continue;
          let tickSize = divs[d] * unitSize;
          let scale = this.getScale(null, unit, tickSize);
          let format = this.format ?? this.getFormat(unit, scale);
          let minLabelDistance =
            this.minLabelDistanceFormatOverride[format] ??
            this.minLabelDistance;
          let labelDistance = tickSize * Math.abs(scale.factor);
          if (
            labelDistance >= minLabelDistance &&
            labelDistance < bestLabelDistance
          ) {
            bestScale = scale;
            bestTicks = divs.map((s) => s * unitSize);
            bestLabelDistance = labelDistance;
            bestFormat = format;
            bestMinLabelDistance = minLabelDistance;
            minRange = tickSize;
          }
        }
      }

      this.scale = bestScale!;
      this.tickSizes = bestTicks
        .filter(
          (ts) => ts * Math.abs(bestScale!.factor) >= this.minTickDistance,
        )
        .map((size) => ({ size, measure: this.tickMeasure }));
      this.resolvedFormat = bestFormat;
      this.resolvedMinLabelDistance = bestMinLabelDistance;
    }

    let lowerTickUnit: string | null = null;
    switch (this.tickMeasure) {
      case "year":
        lowerTickUnit = "month";
        break;
      case "month":
        lowerTickUnit = "day";
        break;
      case "week":
        lowerTickUnit = "day";
        break;
      case "day":
        lowerTickUnit = "hour";
        break;
      case "hour":
        lowerTickUnit = "minute";
        break;
      case "minute":
        lowerTickUnit = "second";
        break;
    }

    if (
      lowerTickUnit &&
      this.minTickUnit &&
      milliSeconds[lowerTickUnit] < milliSeconds[this.minTickUnit]
    )
      lowerTickUnit =
        this.minTickUnit == this.tickMeasure ? null : this.minTickUnit;

    if (lowerTickUnit != null && this.scale) {
      let bestMinorTickSize = Infinity;
      let divisions = this.tickDivisions[lowerTickUnit];
      let unitSize = milliSeconds[lowerTickUnit];
      for (let i = 0; i < divisions.length; i++) {
        let divs = divisions[i];
        for (let d = 0; d < divs.length; d++) {
          let tickSize = divs[d] * unitSize;
          if (
            tickSize * Math.abs(this.scale.factor) >= this.minTickDistance &&
            tickSize < bestMinorTickSize
          ) {
            bestMinorTickSize = tickSize;
          }
        }
      }
      if (bestMinorTickSize != Infinity) {
        this.tickSizes.unshift({
          size: bestMinorTickSize,
          measure: lowerTickUnit,
          noLabels: true,
        });
        if (this.tickSizes.length > 1) {
          let labelStep = this.tickSizes[1].size;
          let lowerScale = this.getScale(null, lowerTickUnit, minRange);
          if (lowerScale.max - lowerScale.min >= labelStep)
            this.scale = lowerScale;
        }
      }
    }

    if (
      isNumber(this.snapToTicks) &&
      this.snapToTicks >= 0 &&
      this.tickSizes.length > 0
    ) {
      let tickSize =
        this.tickSizes[Math.min(this.tickSizes.length - 1, this.snapToTicks)];
      this.scale = this.getScale(tickSize.size, tickSize.measure, minRange);
    }
  }

  getTicks(tickSizes: TickSize[]): (number | Date)[][] {
    return tickSizes.map(({ size, measure }) => {
      let result: (number | Date)[] = [],
        start: number,
        end: number,
        minDate: Date,
        maxDate: Date;
      if (measure == "year") {
        size /= milliSeconds.year;
        minDate = new Date(this.scale.min - this.scale.minPadding);
        maxDate = new Date(this.scale.max + this.scale.maxPadding);
        start = Math.ceil(yearNumber(minDate) / size) * size;
        end = Math.floor(yearNumber(maxDate) / size) * size;
        for (let i = start; i <= end; i += size)
          result.push(new Date(i, 0, 1).getTime());
      } else if (measure == "month") {
        size /= milliSeconds.month;
        minDate = new Date(this.scale.min - this.scale.minPadding);
        maxDate = new Date(this.scale.max + this.scale.maxPadding);
        start = Math.ceil(monthNumber(minDate) / size) * size;
        end = Math.floor(monthNumber(maxDate) / size) * size;
        for (let i = start; i <= end; i += size)
          result.push(new Date(Math.floor(i / 12), i % 12, 1).getTime());
      } else if (measure == "day" || measure == "week") {
        let multiplier = measure == "week" ? 7 : 1;
        size /= milliSeconds.day;
        minDate = new Date(this.scale.min - this.scale.minPadding);
        maxDate = new Date(this.scale.max + this.scale.maxPadding);
        let date = zeroTime(minDate);
        while (date.getTime() < minDate.getTime())
          date.setDate(date.getDate() + 1);
        if (measure == "week") {
          //start on monday
          while (date.getDay() != 1) {
            date.setDate(date.getDate() + 1);
          }
        }
        while (date.getTime() <= maxDate.getTime()) {
          result.push(date);
          date = new Date(date);
          date.setDate(date.getDate() + multiplier);
        }
      } else {
        let minOffset = this.getTimezoneOffset(
          new Date(this.scale.min - this.scale.minPadding),
        );
        let mondayOffset = 4 * milliSeconds.day;
        let date =
          Math.ceil(
            (this.scale.min -
              this.scale.minPadding -
              minOffset -
              mondayOffset) /
              size,
          ) *
            size +
          minOffset +
          mondayOffset;
        while (date <= this.scale.max + this.scale.maxPadding) {
          result.push(date);
          date += size;
        }
      }
      return result;
    });
  }

  mapGridlines(): number[] {
    if (this.tickSizes.length == 0) return [];
    return this.getTicks([this.tickSizes[0]])[0].map((x) => this.map(x));
  }

  book(): void {
    Console.warn(
      "TimeAxis does not support the autoSize flag for column and bar graphs.",
    );
  }
}