import { requestJson } from "@/shared/api/request-json"

import {
  radarMetricKinds,
  radarMetricQualities,
  radarMetricUnits,
  radarPublicationStatuses,
  radarRankSides,
  radarViews,
  sectorTypes,
  type RadarDatesResponse,
  type RadarSectorQuery,
  type RadarHistoryResponse,
  type RadarHistoryMetric,
  type RadarDetailResponse,
  type RadarMember,
  type RadarMetricDefinition,
  type RadarPublication,
  type RadarRankingRow,
  type RadarRankingsQuery,
  type RadarRankingsResponse,
  type StockSectorMembershipResponse,
  type StockSectorRef,
} from "./sector-radar.types"

type JsonRecord = Record<string, unknown>

/**
 * Fetch and validate the available sector-radar publication dates.
 *
 * @param signal - React Query cancellation signal forwarded to fetch.
 * @returns A normalized response whose decimal fields are finite numbers.
 * @throws Error when the server response violates the stable HTTP contract.
 */
export async function getSectorRadarDates(signal?: AbortSignal) {
  const payload = await requestJson<unknown>("/api/v1/sector-radar/dates", {
    signal,
  })
  return parseRadarDatesResponse(payload)
}

/**
 * Fetch one persisted ranking page using the backend's snake-case query names.
 *
 * @param query - URL-backed ranking filters owned by the sector-radar feature.
 * @param signal - React Query cancellation signal forwarded to fetch.
 * @returns A validated and normalized ranking page.
 * @throws Error when the server response violates the stable HTTP contract.
 */
export async function getSectorRadarRankings(
  query: RadarRankingsQuery,
  signal?: AbortSignal,
) {
  const params = new URLSearchParams({
    sector_type: query.sectorType,
    view: query.view,
    rank_change_metric: query.rankChangeMetric,
    rank_change_days: String(query.rankChangeDays),
    side: query.side,
    page: String(query.page),
    page_size: String(query.pageSize),
  })
  if (query.tradeDate) params.set("trade_date", query.tradeDate)
  if (query.search?.trim()) params.set("search", query.search.trim())

  const payload = await requestJson<unknown>(
    `/api/v1/sector-radar/rankings?${params.toString()}`,
    { signal },
  )
  return parseRadarRankingsResponse(payload)
}

/**
 * Validate the dates response at the feature boundary.
 *
 * The shared transport intentionally does not own feature schemas. Decimal
 * strings emitted by Pydantic are converted here so the page never handles
 * mixed string/number arithmetic.
 */
export function parseRadarDatesResponse(value: unknown): RadarDatesResponse {
  const record = readRecord(value, "dates")
  return {
    status: readEnum(record.status, ["success", "no_data"], "dates.status"),
    available_dates: readArray(
      record.available_dates,
      "dates.available_dates",
    ).map((item, index) => readDate(item, `dates.available_dates[${index}]`)),
    current_attempt: readNullablePublication(
      record.current_attempt,
      "dates.current_attempt",
    ),
    last_good: readNullablePublication(record.last_good, "dates.last_good"),
  }
}

/** Validate and normalize one ranking response from the same-repository API. */
export function parseRadarRankingsResponse(
  value: unknown,
): RadarRankingsResponse {
  const record = readRecord(value, "rankings")
  return {
    status: readEnum(record.status, ["success", "no_data"], "rankings.status"),
    requested_trade_date: readNullableDate(
      record.requested_trade_date,
      "rankings.requested_trade_date",
    ),
    sector_type: readEnum(
      record.sector_type,
      sectorTypes,
      "rankings.sector_type",
    ),
    view: readEnum(record.view, radarViews, "rankings.view"),
    rank_change_metric: readEnum(
      record.rank_change_metric,
      radarMetricKinds,
      "rankings.rank_change_metric",
    ),
    rank_change_days: readIntegerInRange(
      record.rank_change_days,
      1,
      5,
      "rankings.rank_change_days",
    ),
    side: readEnum(record.side, radarRankSides, "rankings.side"),
    search: readNullableString(record.search, "rankings.search"),
    publication: readNullablePublication(
      record.publication,
      "rankings.publication",
    ),
    definition: readMetricDefinition(record.definition),
    page: readIntegerInRange(
      record.page,
      1,
      Number.MAX_SAFE_INTEGER,
      "rankings.page",
    ),
    page_size: readIntegerInRange(
      record.page_size,
      1,
      100,
      "rankings.page_size",
    ),
    total: readIntegerInRange(
      record.total,
      0,
      Number.MAX_SAFE_INTEGER,
      "rankings.total",
    ),
    rows: readArray(record.rows, "rankings.rows").map((item, index) =>
      readRankingRow(item, index),
    ),
  }
}

/**
 * Fetch one stock's industries and concepts from the last-good build snapshot.
 *
 * @param tsCode - Stock code such as `000001.SZ`.
 * @param tradeDate - Requested trade date; the backend answers with the
 *   newest snapshot at or before it and reports that exact date.
 * @param signal - React Query cancellation signal forwarded to fetch.
 * @returns A validated membership response with grouped sector references.
 * @throws Error when the server response violates the stable HTTP contract.
 */
export async function getStockSectorMembership(
  tsCode: string,
  tradeDate: string,
  signal?: AbortSignal,
) {
  const params = new URLSearchParams({ trade_date: tradeDate })
  const payload = await requestJson<unknown>(
    `/api/v1/sector-radar/stocks/${encodeURIComponent(tsCode)}/membership?${params.toString()}`,
    { signal },
  )
  return parseStockSectorMembershipResponse(payload)
}

/** Validate one stock-membership response at the feature boundary. */
export function parseStockSectorMembershipResponse(
  value: unknown,
): StockSectorMembershipResponse {
  const record = readRecord(value, "membership")
  return {
    status: readEnum(
      record.status,
      ["success", "no_data"],
      "membership.status",
    ),
    ts_code: readNonEmptyString(record.ts_code, "membership.ts_code"),
    requested_trade_date: readDate(
      record.requested_trade_date,
      "membership.requested_trade_date",
    ),
    trade_date: readNullableDate(record.trade_date, "membership.trade_date"),
    industries: readSectorRefs(record.industries, "membership.industries"),
    concepts: readSectorRefs(record.concepts, "membership.concepts"),
    concept_total: readIntegerInRange(
      record.concept_total,
      0,
      Number.MAX_SAFE_INTEGER,
      "membership.concept_total",
    ),
    concept_limit: readIntegerInRange(
      record.concept_limit,
      1,
      100,
      "membership.concept_limit",
    ),
  }
}

function readSectorRefs(value: unknown, path: string): StockSectorRef[] {
  return readArray(value, path).map((item, index) => {
    const ref = readRecord(item, `${path}[${index}]`)
    return {
      code: readNonEmptyString(ref.code, `${path}[${index}].code`),
      name: readNonEmptyString(ref.name, `${path}[${index}].name`),
    }
  })
}

function readNullablePublication(
  value: unknown,
  path: string,
): RadarPublication | null {
  if (value === null) return null
  const record = readRecord(value, path)
  return {
    publication_id: readNonEmptyString(
      record.publication_id,
      `${path}.publication_id`,
    ),
    target_trade_date: readDate(
      record.target_trade_date,
      `${path}.target_trade_date`,
    ),
    status: readEnum(record.status, radarPublicationStatuses, `${path}.status`),
    source_version: readNonEmptyString(
      record.source_version,
      `${path}.source_version`,
    ),
    universe_version: readNonEmptyString(
      record.universe_version,
      `${path}.universe_version`,
    ),
    metric_versions: readArray(
      record.metric_versions,
      `${path}.metric_versions`,
    ).map((item, index) =>
      readNonEmptyString(item, `${path}.metric_versions[${index}]`),
    ),
    input_hash: readNullableString(record.input_hash, `${path}.input_hash`),
    coverage: readFraction(record.coverage, `${path}.coverage`),
    started_at: readDateTime(record.started_at, `${path}.started_at`),
    finished_at: readNullableDateTime(
      record.finished_at,
      `${path}.finished_at`,
    ),
    error_summary: readNullableString(
      record.error_summary,
      `${path}.error_summary`,
    ),
  }
}

function readMetricDefinition(value: unknown): RadarMetricDefinition {
  const path = "rankings.definition"
  const record = readRecord(value, path)
  return {
    metric_kind: readEnum(
      record.metric_kind,
      radarMetricKinds,
      `${path}.metric_kind`,
    ),
    metric_version: readNonEmptyString(
      record.metric_version,
      `${path}.metric_version`,
    ),
    label: readNonEmptyString(record.label, `${path}.label`),
    unit: readEnum(record.unit, radarMetricUnits, `${path}.unit`),
    implementation_kind: readEnum(
      record.implementation_kind,
      ["independent"],
      `${path}.implementation_kind`,
    ),
    disclaimer: readNonEmptyString(record.disclaimer, `${path}.disclaimer`),
  }
}

function readRankingRow(value: unknown, index: number): RadarRankingRow {
  const path = `rankings.rows[${index}]`
  const record = readRecord(value, path)
  return {
    trade_date: readDate(record.trade_date, `${path}.trade_date`),
    sector_type: readEnum(
      record.sector_type,
      sectorTypes,
      `${path}.sector_type`,
    ),
    sector_code: readNonEmptyString(record.sector_code, `${path}.sector_code`),
    sector_name: readNonEmptyString(record.sector_name, `${path}.sector_name`),
    metric_kind: readEnum(
      record.metric_kind,
      radarMetricKinds,
      `${path}.metric_kind`,
    ),
    metric_version: readNonEmptyString(
      record.metric_version,
      `${path}.metric_version`,
    ),
    implementation_kind: readEnum(
      record.implementation_kind,
      ["independent"],
      `${path}.implementation_kind`,
    ),
    unit: readEnum(record.unit, radarMetricUnits, `${path}.unit`),
    metric_value: readNullableFiniteNumber(
      record.metric_value,
      `${path}.metric_value`,
    ),
    pct_change: readNullableFiniteNumber(
      record.pct_change ?? null,
      `${path}.pct_change`,
    ),
    daily_net_amount_yuan: readNullableFiniteNumber(
      record.daily_net_amount_yuan ?? null,
      `${path}.daily_net_amount_yuan`,
    ),
    daily_ratio: readNullableFiniteNumber(
      record.daily_ratio ?? null,
      `${path}.daily_ratio`,
    ),
    on_list_count:
      record.on_list_count == null
        ? null
        : readIntegerInRange(
            record.on_list_count,
            0,
            30,
            `${path}.on_list_count`,
          ),
    history_available_days: readIntegerInRange(
      record.history_available_days ?? 0,
      0,
      30,
      `${path}.history_available_days`,
    ),
    quality: readEnum(record.quality, radarMetricQualities, `${path}.quality`),
    member_count: readIntegerInRange(
      record.member_count,
      0,
      Number.MAX_SAFE_INTEGER,
      `${path}.member_count`,
    ),
    valid_sample_count: readIntegerInRange(
      record.valid_sample_count,
      0,
      Number.MAX_SAFE_INTEGER,
      `${path}.valid_sample_count`,
    ),
    membership_coverage: readFraction(
      record.membership_coverage,
      `${path}.membership_coverage`,
    ),
    moneyflow_coverage: readFraction(
      record.moneyflow_coverage,
      `${path}.moneyflow_coverage`,
    ),
    rank_position: readNullableInteger(
      record.rank_position,
      1,
      `${path}.rank_position`,
    ),
    rank_percentile: readNullablePositiveNumber(
      record.rank_percentile,
      100,
      `${path}.rank_percentile`,
    ),
    rank_change_days: readIntegerInRange(
      record.rank_change_days,
      1,
      5,
      `${path}.rank_change_days`,
    ),
    rank_change: readNullableInteger(
      record.rank_change,
      Number.MIN_SAFE_INTEGER,
      `${path}.rank_change`,
    ),
  }
}

function readRecord(value: unknown, path: string): JsonRecord {
  if (typeof value !== "object" || value === null || Array.isArray(value)) {
    throw contractError(path, "must be an object")
  }
  return value as JsonRecord
}

function readArray(value: unknown, path: string): unknown[] {
  if (!Array.isArray(value)) throw contractError(path, "must be an array")
  return value
}

function readEnum<const Values extends readonly string[]>(
  value: unknown,
  allowed: Values,
  path: string,
): Values[number] {
  if (typeof value !== "string" || !allowed.includes(value)) {
    throw contractError(path, `must be one of ${allowed.join(", ")}`)
  }
  return value as Values[number]
}

function readNonEmptyString(value: unknown, path: string): string {
  if (typeof value !== "string" || value.trim().length === 0) {
    throw contractError(path, "must be a non-empty string")
  }
  return value
}

function readNullableString(value: unknown, path: string): string | null {
  if (value === null) return null
  if (typeof value !== "string")
    throw contractError(path, "must be a string or null")
  return value
}

function readDate(value: unknown, path: string): string {
  const text = readNonEmptyString(value, path)
  const match = /^(\d{4})-(\d{2})-(\d{2})$/.exec(text)
  if (!match) throw contractError(path, "must be an ISO trade date")
  const parsed = new Date(`${text}T00:00:00Z`)
  if (
    Number.isNaN(parsed.getTime()) ||
    parsed.getUTCFullYear() !== Number(match[1]) ||
    parsed.getUTCMonth() + 1 !== Number(match[2]) ||
    parsed.getUTCDate() !== Number(match[3])
  ) {
    throw contractError(path, "must be a valid trade date")
  }
  return text
}

function readNullableDate(value: unknown, path: string): string | null {
  return value === null ? null : readDate(value, path)
}

function readDateTime(value: unknown, path: string): string {
  const text = readNonEmptyString(value, path)
  if (!Number.isFinite(Date.parse(text))) {
    throw contractError(path, "must be an ISO date-time")
  }
  return text
}

function readNullableDateTime(value: unknown, path: string): string | null {
  return value === null ? null : readDateTime(value, path)
}

function readFiniteNumber(value: unknown, path: string): number {
  const number =
    typeof value === "number"
      ? value
      : typeof value === "string" &&
          /^[+-]?(?:\d+(?:\.\d*)?|\.\d+)(?:[eE][+-]?\d+)?$/.test(value.trim())
        ? Number(value)
        : Number.NaN
  if (!Number.isFinite(number)) throw contractError(path, "must be finite")
  return number
}

function readNullableFiniteNumber(value: unknown, path: string): number | null {
  return value === null ? null : readFiniteNumber(value, path)
}

function readFraction(value: unknown, path: string): number {
  const number = readFiniteNumber(value, path)
  if (number < 0 || number > 1)
    throw contractError(path, "must be between 0 and 1")
  return number
}

function readIntegerInRange(
  value: unknown,
  min: number,
  max: number,
  path: string,
): number {
  const number = readFiniteNumber(value, path)
  if (!Number.isInteger(number) || number < min || number > max) {
    throw contractError(path, `must be an integer between ${min} and ${max}`)
  }
  return number
}

function readNullableInteger(
  value: unknown,
  min: number,
  path: string,
): number | null {
  if (value === null) return null
  return readIntegerInRange(value, min, Number.MAX_SAFE_INTEGER, path)
}

function readNullablePositiveNumber(
  value: unknown,
  max: number,
  path: string,
): number | null {
  if (value === null) return null
  const number = readFiniteNumber(value, path)
  if (number <= 0 || number > max) {
    throw contractError(path, `must be greater than 0 and at most ${max}`)
  }
  return number
}

function contractError(path: string, reason: string): Error {
  return new Error(`Invalid sector radar response: ${path} ${reason}`)
}

/** Fetch persisted history for a sector/date; forward cancellation and reject malformed decimals. */
export async function getSectorRadarHistory(
  query: RadarSectorQuery,
  signal?: AbortSignal,
) {
  const payload = await requestJson<unknown>(
    sectorResourceUrl(query, "history"),
    { signal },
  )
  return parseRadarHistoryResponse(payload)
}

/** Fetch persisted detail on demand; no supplier calls originate from the browser. */
export async function getSectorRadarDetail(
  query: RadarSectorQuery,
  signal?: AbortSignal,
) {
  const payload = await requestJson<unknown>(
    sectorResourceUrl(query, "detail"),
    { signal },
  )
  return parseRadarDetailResponse(payload)
}

function sectorResourceUrl(
  query: RadarSectorQuery,
  resource: "history" | "detail",
) {
  const params = new URLSearchParams({ trade_date: query.tradeDate })
  return `/api/v1/sector-radar/sectors/${query.sectorType}/${encodeURIComponent(query.sectorCode)}/${resource}?${params}`
}

function readSectorIdentity(record: JsonRecord, path: string) {
  return {
    status: readEnum(record.status, ["success", "no_data"], `${path}.status`),
    requested_trade_date: readNullableDate(
      record.requested_trade_date,
      `${path}.requested_trade_date`,
    ),
    trade_date: readNullableDate(record.trade_date, `${path}.trade_date`),
    publication: readNullablePublication(
      record.publication,
      `${path}.publication`,
    ),
    sector_type: readEnum(
      record.sector_type,
      sectorTypes,
      `${path}.sector_type`,
    ),
    sector_code: readNonEmptyString(record.sector_code, `${path}.sector_code`),
    sector_name: readNullableString(record.sector_name, `${path}.sector_name`),
  }
}

/** Normalize the finite Decimal fields while preserving missing ranks as null. */
export function parseRadarHistoryResponse(
  value: unknown,
): RadarHistoryResponse {
  const record = readRecord(value, "history")
  return {
    ...readSectorIdentity(record, "history"),
    window_size: readIntegerInRange(
      record.window_size,
      1,
      30,
      "history.window_size",
    ),
    available_days: readIntegerInRange(
      record.available_days,
      0,
      30,
      "history.available_days",
    ),
    points: readArray(record.points, "history.points").map((value, index) => {
      const path = `history.points[${index}]`
      const point = readRecord(value, path)
      return {
        trade_date: readDate(point.trade_date, `${path}.trade_date`),
        publication_id: readNullableString(
          point.publication_id,
          `${path}.publication_id`,
        ),
        ...readMetricSummary(point, path),
      }
    }),
  }
}

function readMetricSummary(record: JsonRecord, path: string) {
  return {
    amount: readHistoryMetric(record.amount, `${path}.amount`),
    ratio: readHistoryMetric(record.ratio, `${path}.ratio`),
    swing: readHistoryMetric(record.swing, `${path}.swing`),
  }
}

function readHistoryMetric(value: unknown, path: string): RadarHistoryMetric {
  const record = readRecord(value, path)
  return {
    rank_position: readNullableInteger(
      record.rank_position,
      1,
      `${path}.rank_position`,
    ),
    rank_percentile: readNullablePositiveNumber(
      record.rank_percentile,
      100,
      `${path}.rank_percentile`,
    ),
    pool_size: readIntegerInRange(
      record.pool_size,
      0,
      Number.MAX_SAFE_INTEGER,
      `${path}.pool_size`,
    ),
    metric_value: readNullableFiniteNumber(
      record.metric_value,
      `${path}.metric_value`,
    ),
    missing: readBoolean(record.missing, `${path}.missing`),
    in_top: readBoolean(record.in_top, `${path}.in_top`),
    in_bottom: readBoolean(record.in_bottom, `${path}.in_bottom`),
  }
}

function readBoolean(value: unknown, path: string): boolean {
  if (typeof value !== "boolean") throw contractError(path, "must be a boolean")
  return value
}

function readMembers(value: unknown, path: string): RadarMember[] {
  return readArray(value, path).map((value, index) => {
    const itemPath = `${path}[${index}]`
    const record = readRecord(value, itemPath)
    return {
      ts_code: readNonEmptyString(record.ts_code, `${itemPath}.ts_code`),
      name: readNonEmptyString(record.name, `${itemPath}.name`),
      pct_change: readNullableFiniteNumber(
        record.pct_change,
        `${itemPath}.pct_change`,
      ),
      net_amount_yuan: readNullableFiniteNumber(
        record.net_amount_yuan,
        `${itemPath}.net_amount_yuan`,
      ),
      active_buy_net_amount_yuan: readNullableFiniteNumber(
        record.active_buy_net_amount_yuan,
        `${itemPath}.active_buy_net_amount_yuan`,
      ),
    }
  })
}

/** Validate the full detail payload, including independent member metrics and overlaps. */
export function parseRadarDetailResponse(value: unknown): RadarDetailResponse {
  const record = readRecord(value, "detail")
  const leading =
    record.leading_stock === null
      ? null
      : readRecord(record.leading_stock, "detail.leading_stock")
  const leaders = readRecord(record.leaders, "detail.leaders")
  function readLeaders(key: string) {
    const path = `detail.leaders.${key}`
    const group = readRecord(leaders[key], path)
    return {
      top: readMembers(group.top, `${path}.top`),
      bottom: readMembers(group.bottom, `${path}.bottom`),
    }
  }
  return {
    ...readSectorIdentity(record, "detail"),
    pct_change: readNullableFiniteNumber(
      record.pct_change,
      "detail.pct_change",
    ),
    leading_stock:
      leading === null
        ? null
        : {
            ts_code: readNonEmptyString(
              leading.ts_code,
              "detail.leading_stock.ts_code",
            ),
            name: readNullableString(leading.name, "detail.leading_stock.name"),
          },
    summary: readMetricSummary(
      readRecord(record.summary, "detail.summary"),
      "detail.summary",
    ),
    history: parseRadarHistoryResponse(record.history),
    members: readMembers(record.members, "detail.members"),
    leaders: {
      pct_change: readLeaders("pct_change"),
      net_amount_yuan: readLeaders("net_amount_yuan"),
      active_buy_net_amount_yuan: readLeaders("active_buy_net_amount_yuan"),
    },
    similar_sectors: readArray(
      record.similar_sectors,
      "detail.similar_sectors",
    ).map((value, index) => {
      const path = `detail.similar_sectors[${index}]`
      const sector = readRecord(value, path)
      return {
        sector_type: readEnum(
          sector.sector_type,
          sectorTypes,
          `${path}.sector_type`,
        ),
        sector_code: readNonEmptyString(
          sector.sector_code,
          `${path}.sector_code`,
        ),
        sector_name: readNonEmptyString(
          sector.sector_name,
          `${path}.sector_name`,
        ),
        overlap_ratio: readFraction(
          sector.overlap_ratio,
          `${path}.overlap_ratio`,
        ),
        intersection_count: readIntegerInRange(
          sector.intersection_count,
          0,
          Number.MAX_SAFE_INTEGER,
          `${path}.intersection_count`,
        ),
        union_count: readIntegerInRange(
          sector.union_count,
          1,
          Number.MAX_SAFE_INTEGER,
          `${path}.union_count`,
        ),
      }
    }),
  }
}