import { z } from "zod";

const SIGNS = [
  "Aries",
  "Taurus",
  "Gemini",
  "Cancer",
  "Leo",
  "Virgo",
  "Libra",
  "Scorpio",
  "Sagittarius",
  "Capricorn",
  "Aquarius",
  "Pisces",
] as const;

const PLANETS = [
  "Sun",
  "Moon",
  "Mars",
  "Mercury",
  "Jupiter",
  "Venus",
  "Saturn",
  "Rahu",
  "Ketu",
] as const;

const PLANET_LABEL: Record<(typeof PLANETS)[number], string> = {
  Sun: "日",
  Moon: "月",
  Mars: "火",
  Mercury: "水",
  Jupiter: "木",
  Venus: "金",
  Saturn: "土",
  Rahu: "罗",
  Ketu: "计",
};

const SIGN_NUMBER: Record<string, number> = {
  Aries: 1,
  Taurus: 2,
  Gemini: 3,
  Cancer: 4,
  Leo: 5,
  Virgo: 6,
  Libra: 7,
  Scorpio: 8,
  Sagittarius: 9,
  Capricorn: 10,
  Aquarius: 11,
  Pisces: 12,
  白羊: 1,
  金牛: 2,
  双子: 3,
  巨蟹: 4,
  狮子: 5,
  处女: 6,
  天秤: 7,
  天蝎: 8,
  射手: 9,
  摩羯: 10,
  水瓶: 11,
  双鱼: 12,
  白羊座: 1,
  金牛座: 2,
  双子座: 3,
  巨蟹座: 4,
  狮子座: 5,
  处女座: 6,
  天秤座: 7,
  天蝎座: 8,
  射手座: 9,
  摩羯座: 10,
  水瓶座: 11,
  双鱼座: 12,
};

const FENCE_RE = /(?:\n[ \t]*)?```jyotish-chart\n[\s\S]*?```(?:\n[ \t]*)?/g;

export const reportChartBlockSchema = z.strictObject({
  version: z.literal(1),
  id: z.string().regex(/^(D\d{1,3}|MOON)$/),
  title: z.string().max(120),
  layout: z.literal("north"),
  ascendant: z.strictObject({
    sign: z.enum(SIGNS),
    degree: z.number().gte(0).lt(30),
  }),
  planets: z.array(z.strictObject({
    name: z.enum(PLANETS),
    sign: z.enum(SIGNS),
    degree: z.number().gte(0).lt(30),
    retrograde: z.boolean(),
  })).max(9),
});

export type ReportChartBlock = z.infer<typeof reportChartBlockSchema>;

export type NorthIndianChartModel = {
  houses: { houseNumber: number; sign: string; occupants: string[] }[];
  planets?: { name: string; retrograde: boolean }[];
};

export function parseReportChartBlock(source: string): ReportChartBlock | null {
  try {
    return reportChartBlockSchema.parse(JSON.parse(source));
  } catch {
    return null;
  }
}

function integerDegree(degree: number): number {
  const value = Math.floor(degree);
  if (value >= 30) return 29;
  if (value < 0) return 0;
  return value;
}

export function planetDisplayLabel(
  name: (typeof PLANETS)[number],
  degree: number,
  retrograde: boolean,
): string {
  const body = PLANET_LABEL[name];
  const suffix = retrograde ? "逆" : "";
  return `${body}${suffix} ${integerDegree(degree)}°`;
}

export function signOrdinal(sign: string): number | null {
  return SIGN_NUMBER[sign] ?? null;
}

export function chartAriaLabel(id: ReportChartBlock["id"]): string {
  return id === "MOON" ? "月亮参考盘" : `${id} 北印度盘`;
}

export function toNorthIndianChart(block: ReportChartBlock): NorthIndianChartModel {
  const ascIndex = SIGNS.indexOf(block.ascendant.sign);
  const occupantsByHouse: string[][] = Array.from({ length: 12 }, () => []);
  for (const planet of block.planets) {
    const signIndex = SIGNS.indexOf(planet.sign);
    const houseNumber = ((signIndex - ascIndex + 12) % 12) + 1;
    occupantsByHouse[houseNumber - 1].push(
      planetDisplayLabel(planet.name, planet.degree, planet.retrograde),
    );
  }
  return {
    houses: Array.from({ length: 12 }, (_, index) => ({
      houseNumber: index + 1,
      sign: SIGNS[(ascIndex + index + 12) % 12],
      occupants: occupantsByHouse[index],
    })),
    planets: block.planets.map((planet) => ({
      name: PLANET_LABEL[planet.name],
      retrograde: planet.retrograde,
    })),
  };
}

export function stripReportChartBlocks(markdown: string): string {
  const stripped = markdown.replace(FENCE_RE, "\n\n");
  return stripped.replace(/\n{3,}/g, "\n\n");
}