import { config } from '../config.js'
import { berlinDateTime } from './berlinTime.js'
import { withLocks } from './keyedLock.js'
import {
  listDocuments,
  getDocument,
  createDocument,
  Query,
  ID,
} from './appwriteAdmin.js'

const WSID_START = 100000
// worksheets.details ist auf 4000 Zeichen begrenzt
const DETAILS_MAX_LENGTH = 3900

/** Pusht das System-Konto selbst (automatische Commits) - dafuer kein Arbeitsblatt. */
export function isSystemPusher(pusher) {
  const name = pusher?.username || pusher?.login || ''
  return name.toLowerCase() === config.gitea.systemUser.toLowerCase()
}

async function generateNextWsid() {
  const docs = await listDocuments(config.collections.worksheets, [
    Query.orderDesc('wsid'),
    Query.limit(1),
  ])
  const highest = docs[0]?.wsid ? parseInt(docs[0].wsid, 10) : WSID_START - 1
  return String(Math.max(WSID_START, highest + 1))
}

async function gitWorksheetExists(woid, commitSha) {
  if (!commitSha) return false
  const docs = await listDocuments(config.collections.worksheets, [
    Query.equal('woid', woid),
    Query.limit(100),
  ])
  const marker = `Commit: ${commitSha.slice(0, 7)}`
  return docs.some((doc) => doc.details?.includes(marker) || doc.details?.includes(commitSha))
}

function formatCommitLines(commits, repoFullName) {
  if (!Array.isArray(commits) || commits.length === 0) {
    return '- (keine Commit-Details im Webhook)'
  }

  return commits
    .map((commit) => {
      const sha = (commit.id || commit.sha || '').slice(0, 7)
      // Commit-Titel + Beschreibung (Body) uebernehmen
      const [title, ...bodyLines] = String(commit.message || '').trim().split('\n')
      const author = commit.author?.name || commit.committer?.name || 'Unbekannt'
      const url = commit.url || `${config.gitea.baseUrl}/${repoFullName}/commit/${commit.id || commit.sha}`
      const body = bodyLines
        .map((line) => line.trim())
        .filter(Boolean)
        .map((line) => `    ${line}`)
        .join('\n')
      return `- [${sha}](${url}): ${title} (${author})${body ? `\n${body}` : ''}`
    })
    .join('\n')
}

export async function createGitPushWorksheet({
  ticketId,
  repoFullName,
  branch,
  commits = [],
  pusher,
  commitSha,
  pushedAt = new Date(),
}) {
  if (!ticketId) return null

  if (isSystemPusher(pusher)) {
    return { skipped: true, reason: 'system_pusher' }
  }

  let workorder
  try {
    workorder = await getDocument(config.collections.workorders, ticketId)
  } catch {
    console.warn('[gitWorksheet] Workorder nicht gefunden:', ticketId)
    return null
  }

  const woid = workorder.woid
  if (!woid) return null

  // Gesperrt je Ticket+Commit, damit zwei gleichzeitige Zustellungen desselben Webhooks
  // (Gitea liefert bei Bedarf erneut zu) nicht zweimal denselben Duplikat-Check bestehen
  // und zwei Arbeitsblaetter anlegen.
  const lockKey = `ws:${woid}:${(commitSha || '').slice(0, 7)}`
  return withLocks([lockKey], async () => {
    if (await gitWorksheetExists(woid, commitSha)) {
      return { skipped: true, reason: 'duplicate_commit' }
    }

    const wsid = await generateNextWsid()
    const pusherName = pusher?.full_name || pusher?.username || pusher?.login || 'Gitea'
    const latestCommit = commits[commits.length - 1] || commits[0]
    let details = [
      `Git Push auf \`${repoFullName}\` (Branch: ${branch})`,
      `Commit: ${commitSha?.slice(0, 7) || latestCommit?.id?.slice(0, 7) || '?'}`,
      '',
      formatCommitLines(commits, repoFullName),
    ].join('\n')
    if (details.length > DETAILS_MAX_LENGTH) {
      details = `${details.slice(0, DETAILS_MAX_LENGTH)}\n… (gekuerzt)`
    }

    // Endzeit = Push-Zeitpunkt in deutscher Zeit (MESZ/MEZ). Startzeit bleibt leer und wird
    // im Ticketsystem nachgetragen ("Zeit nachtragen") - erst dann zaehlt die Arbeitszeit.
    const { date, time } = berlinDateTime(pushedAt)
    const worksheet = await createDocument(
      config.collections.worksheets,
      {
        wsid,
        woid: String(woid),
        workorderId: ticketId,
        employeeId: 'gitea',
        employeeName: pusherName,
        employeeShort: 'GIT',
        serviceType: 'GIT',
        oldStatus: workorder.status || '',
        newStatus: workorder.status || '',
        oldResponseLevel: workorder.response || '',
        newResponseLevel: workorder.response || '',
        totalTime: 0,
        startDate: date,
        startTime: '',
        endDate: date,
        endTime: time,
        details,
        isComment: true,
        createdAt: new Date().toISOString(),
      },
      ID.unique()
    )

    // ticket + worksheet fuer die Push-Zeitmail (routes/webhook/gitea.js), nicht fuer die Webhook-Antwort
    return { created: true, wsid, worksheetId: worksheet.$id, ticket: workorder, worksheet }
  })
}