import { useMemo } from 'react'
import { useMarketLeads } from './useMarketLeads'
import { useMarktHinweise } from './useMarktHinweise'
import { useCrmLeads } from './useCrmLeads'
import { LeadChannel } from '../domain/unifiedLead'
import type { UnifiedLead } from '../domain/unifiedLead'
import type { MarktHinweis } from '../domain/marktHinweis'
import type { CrmLead } from '../domain/crmLead'
import { CRM_LEAD_STAGE_LABELS } from '../domain/crmLead'
import { ASSET_TYPE_LABELS } from '../lib/constants'
import type { MarketLead } from './useMarketLeads'

/**
 * Zusammengeführte Leadliste aller drei Kanäle (Runde 5, §12).
 *
 * Die drei Quellen bleiben getrennt erfasst — KI-Signale entstehen aus
 * Marktbeobachtung, Netzwerk-Hinweise aus Gesprächen, CRM-Leads aus dem
 * Vertriebssystem. Zusammengelegt werden sie erst hier, für die Anzeige, und
 * jeder Eintrag behält seine Kanalherkunft im Feld `channel`.
 *
 * Ein gemeinsamer Provider für alle drei wäre der falsche Weg: die Quellen
 * haben unterschiedliche Lebenszyklen und werden später von verschiedenen
 * Systemen bedient.
 */

function areaText(min?: number, max?: number): string | null {
  if (min != null && max != null && min !== max) return `${min}–${max} m²`
  if (max != null) return `${max} m²`
  if (min != null) return `${min} m²`
  return null
}

function fromMarketLead(lead: MarketLead): UnifiedLead {
  const { signal } = lead
  return {
    id: signal.id,
    channel: LeadChannel.KI_SIGNAL,
    title: signal.companyName ?? signal.locationHint,
    subtitle: signal.title ?? 'Erkanntes Nachfragesignal',
    meta: `${signal.locationHint} · Horizont ${signal.timeHorizonMonths} Mo.`,
    receivedAt: signal.updatedAt || signal.createdAt,
    signal,
    matchingProperties: lead.matchingProperties,
  }
}

function fromHinweis(hinweis: MarktHinweis): UnifiedLead {
  const displayName = !hinweis.isAnonymized && hinweis.companyName ? hinweis.companyName : 'Anonymer Hinweis'
  const area = areaText(hinweis.areaSqmMin, hinweis.areaSqmMax)
  const assetLabel = ASSET_TYPE_LABELS[hinweis.assetType] ?? hinweis.assetType
  return {
    id: hinweis.id,
    channel: LeadChannel.NETZWERK,
    title: displayName,
    subtitle: hinweis.direction === 'SUCHE' ? `Sucht ${assetLabel}` : `Fläche wird verfügbar — ${assetLabel}`,
    meta: [hinweis.locationHint, area, hinweis.createdBy].filter(Boolean).join(' · '),
    receivedAt: hinweis.createdAt,
    hinweis,
  }
}

function fromCrmLead(crmLead: CrmLead): UnifiedLead {
  const area = areaText(crmLead.areaSqmMin, crmLead.areaSqmMax)
  const assetLabel = ASSET_TYPE_LABELS[crmLead.assetType] ?? crmLead.assetType
  return {
    id: crmLead.id,
    channel: LeadChannel.CRM,
    title: crmLead.companyName,
    subtitle: `${CRM_LEAD_STAGE_LABELS[crmLead.stage]} — sucht ${assetLabel}`,
    meta: [crmLead.locationHint, area, crmLead.ownerName].filter(Boolean).join(' · '),
    receivedAt: crmLead.lastContactAt,
    crmLead,
  }
}

export function useUnifiedLeads(): { data: UnifiedLead[]; isLoading: boolean } {
  const { data: marketLeads, isLoading: marketLoading } = useMarketLeads()
  const { data: hinweise = [], isLoading: hinweiseLoading } = useMarktHinweise()
  const { data: crmLeads = [], isLoading: crmLoading } = useCrmLeads()

  const data = useMemo(
    () =>
      [
        ...marketLeads.map(fromMarketLead),
        ...hinweise.map(fromHinweis),
        ...crmLeads.map(fromCrmLead),
      ].sort((a, b) => b.receivedAt.localeCompare(a.receivedAt)),
    [marketLeads, hinweise, crmLeads],
  )

  return { data, isLoading: marketLoading || hinweiseLoading || crmLoading }
}