import { computed, ref, watch } from 'vue'
import { getAllPrices } from '@/api/home'
import type { Product } from '@/models/products'
import { getProductsCatalog, getProductsCatalogRef } from '@/composables/useProductsCatalog'
import { getProductBuyPrice, resolvePriceOffsetRatio } from '@/utils/productPrice'
import { isKatodMesGroup, isMaftolMesGroup, isShamshMesGroup } from '@/utils/productDealMethod'
import { getTradeBuyPrice, getTradeSellPrice, lastPrice } from '@/utils/price'

export type ChartMetalType = 'katod' | 'maftol' | 'shamsh'

type ChartPoint = [number, number]

/** Module-level chart state — one dataset shared by mobile and desktop PriceChart instances. */
const priceChartSeries = ref<{ name: string; data: ChartPoint[] }[]>([
  { name: 'قیمت', data: [] },
])
const rawChartPoints = ref<ChartPoint[]>([])
const chartSelection = ref('DAILY')
const chartLoading = ref(false)
const selectedChartMetal = ref<ChartMetalType>('katod')
const catalogProducts = getProductsCatalogRef()

function resolveChartProducts(products: Product[]) {
  return {
    katod: findKatodProduct(products),
    maftol: findMaftolProduct(products),
    shamsh: findShamshProduct(products),
  }
}

/** نسبت مفتول به کاتد — reactive به قیمت لحظه‌ای و کاتالوگ محصولات */
const maftolChartRatio = computed(() => {
  void lastPrice.value?.price_last

  const { katod, maftol } = resolveChartProducts(catalogProducts.value)
  return deriveMetalChartRatio(maftol, katod)
})

/** نسبت شمش مس به کاتد */
const shamshChartRatio = computed(() => {
  void lastPrice.value?.price_last

  const { katod, shamsh } = resolveChartProducts(catalogProducts.value)
  return deriveMetalChartRatio(shamsh, katod)
})

const selectedMetalChartRatio = computed(() => {
  if (selectedChartMetal.value === 'maftol') {
    return maftolChartRatio.value
  }
  if (selectedChartMetal.value === 'shamsh') {
    return shamshChartRatio.value
  }
  return 0
})

let chartFetchPromise: Promise<void> | null = null
let chartInitialized = false
let metalOffsetPromise: Promise<void> | null = null
let metalOffsetLoaded = false

function findKatodProduct(products: Product[]) {
  return (
    products.find((product) => isKatodMesGroup(product.group_type))
    ?? products.find((product) => (product.title ?? '').includes('کاتد'))
  )
}

function findMaftolProduct(products: Product[]) {
  return (
    products.find((product) => isMaftolMesGroup(product.group_type))
    ?? products.find((product) => (product.title ?? '').includes('مفتول'))
  )
}

function findShamshProduct(products: Product[]) {
  return products.find((product) =>
    isShamshMesGroup(product.group_type, product.title)
  )
}

function applyChartRatio(basePrice: number, ratio: number) {
  if (!ratio) {
    return basePrice
  }

  return Math.round(basePrice + basePrice * ratio)
}

/** بالاترین/پایین‌ترین امروز — برای boursecu با نسبت مفتول/شمش نسبت به کاتد */
export function resolveMetalDayRangePrices(options: {
  price: { up?: { buy?: number; sell?: number }; buy?: number; sell?: number; price_last?: number } | null | undefined
  metal: ChartMetalType
  metalRatio: number
}) {
  const baseHigh = options.price?.up?.buy ?? getTradeBuyPrice(options.price as Parameters<typeof getTradeBuyPrice>[0])
  const baseLow = options.price?.up?.sell ?? getTradeSellPrice(options.price as Parameters<typeof getTradeSellPrice>[0])

  if (options.metal === 'katod') {
    return { high: baseHigh, low: baseLow }
  }

  return {
    high: applyChartRatio(baseHigh, options.metalRatio),
    low: applyChartRatio(baseLow, options.metalRatio),
  }
}

function deriveMetalChartRatio(metalProduct?: Product, katodProduct?: Product) {
  const metalOffset = resolvePriceOffsetRatio(metalProduct?.price_offset_percent)
  if (metalOffset) {
    return metalOffset
  }

  if (!metalProduct) {
    return 0
  }

  const liveBuy = getTradeBuyPrice(lastPrice.value)
  const katodLive = katodProduct ? getProductBuyPrice(katodProduct) : liveBuy
  const metalLive = getProductBuyPrice(metalProduct)

  const katodStatic = Number(katodProduct?.price ?? 0) + Number(katodProduct?.price_profit ?? 0)
  const metalStatic = Number(metalProduct.price ?? 0) + Number(metalProduct.price_profit ?? 0)

  const referencePrice = katodLive || liveBuy || katodStatic
  const derivedMetalPrice = metalLive || metalStatic

  if (!referencePrice || !derivedMetalPrice || referencePrice === derivedMetalPrice) {
    return 0
  }

  return (derivedMetalPrice - referencePrice) / referencePrice
}

function normalizeChartTimestamp(timestamp: number) {
  return timestamp < 1_000_000_000_000 ? timestamp * 1000 : timestamp
}

function resolvePricesMap(response: unknown): Record<string, Array<{ timestamp: number; value: number }>> | null {
  if (!response || typeof response !== 'object') {
    return null
  }

  const body = response as Record<string, unknown>
  const nested = body.data

  if (nested && typeof nested === 'object' && 'prices' in nested) {
    return (nested as { prices: Record<string, Array<{ timestamp: number; value: number }>> }).prices
  }

  if ('prices' in body) {
    return body.prices as Record<string, Array<{ timestamp: number; value: number }>>
  }

  return null
}

function buildChartPoints(items: Array<{ timestamp: number; value: number }>): ChartPoint[] {
  return items.map((item) => [
    normalizeChartTimestamp(item.timestamp),
    item.value - 1,
  ])
}

function syncChartSeries() {
  const ratio = selectedMetalChartRatio.value
  const data =
    selectedChartMetal.value !== 'katod'
      ? rawChartPoints.value.map(
          ([timestamp, value]) =>
            [timestamp, applyChartRatio(value, ratio)] as ChartPoint
        )
      : rawChartPoints.value

  priceChartSeries.value[0].data = data
}

watch([selectedChartMetal, maftolChartRatio, shamshChartRatio], () => {
  syncChartSeries()
})

async function fetchPrices(force = false) {
  if (!force && chartInitialized && rawChartPoints.value.length > 0) {
    syncChartSeries()
    return
  }

  if (!force && chartFetchPromise) {
    return chartFetchPromise
  }

  chartFetchPromise = (async () => {
    try {
      chartLoading.value = true
      const response = await getAllPrices()
      const data = resolvePricesMap(response)
      const selectedData = data?.[chartSelection.value] ?? []
      rawChartPoints.value = buildChartPoints(selectedData)
      syncChartSeries()
      chartInitialized = true
    } catch (error) {
      console.error('Error fetching prices:', error)
    } finally {
      chartLoading.value = false
      chartFetchPromise = null
    }
  })()

  return chartFetchPromise
}

async function loadMetalChartOffsets(force = false) {
  if (!force && metalOffsetLoaded && catalogProducts.value.length > 0) {
    return
  }

  if (!force && metalOffsetPromise) {
    return metalOffsetPromise
  }

  metalOffsetPromise = (async () => {
    try {
      await getProductsCatalog(force)
      syncChartSeries()
      metalOffsetLoaded = true
    } catch (error) {
      console.error('Error loading boursecu chart metal ratios:', error)
      syncChartSeries()
    } finally {
      metalOffsetPromise = null
    }
  })()

  return metalOffsetPromise
}

function updateChartData(timeline: string) {
  chartSelection.value = timeline
  void fetchPrices(true)
}

function setChartMetal(metal: ChartMetalType) {
  selectedChartMetal.value = metal

  if (metal !== 'katod' && !catalogProducts.value.length) {
    void loadMetalChartOffsets(true)
  }
}

export function usePriceChart() {
  return {
    priceChartSeries,
    chartSelection,
    chartLoading,
    selectedChartMetal,
    maftolChartRatio,
    shamshChartRatio,
    selectedMetalChartRatio,
    updateChartData,
    fetchPrices,
    loadMaftolOffset: loadMetalChartOffsets,
    loadMetalChartOffsets,
    setChartMetal,
  }
}

export function fetchHomeChartPrices(force = false) {
  return fetchPrices(force)
}

export function loadHomeMaftolOffset(force = false) {
  return loadMetalChartOffsets(force)
}

export function resetHomePriceChart() {
  priceChartSeries.value = [{ name: 'قیمت', data: [] }]
  rawChartPoints.value = []
  chartSelection.value = 'DAILY'
  selectedChartMetal.value = 'katod'
  chartInitialized = false
  chartFetchPromise = null
  metalOffsetLoaded = false
  metalOffsetPromise = null
}