import { getAutomationRunLogs } from '@/modules/automate/clients/executionEngine'
import { ExecutionEngineFailedResponseError } from '@/modules/automate/errors/executionEngine'
import {
  getAutomationProject,
  getAutomationRunWithToken
} from '@/modules/automate/repositories/automations'
import { corsMiddleware } from '@/modules/core/configs/cors'
import { getStream } from '@/modules/core/repositories/streams'
import {
  contextRequiresStream,
  validateResourceAccess,
  validateScope,
  validateServerRole,
  validateStreamRole
} from '@/modules/shared/authz'
import { authMiddlewareCreator } from '@/modules/shared/middleware'
import { Roles, Scopes } from '@speckle/shared'
import { Application } from 'express'

export default (app: Application) => {
  app.get(
    '/api/automate/automations/:automationId/runs/:runId/logs',
    corsMiddleware(),
    authMiddlewareCreator([
      validateServerRole({ requiredRole: Roles.Server.Guest }),
      validateScope({ requiredScope: Scopes.Streams.Read }),
      contextRequiresStream({ getStream, getAutomationProject }),
      validateStreamRole({ requiredRole: Roles.Stream.Owner }),
      validateResourceAccess
    ]),
    async (req, res) => {
      const automationId = req.params.automationId
      const runId = req.params.runId

      const run = await getAutomationRunWithToken({
        automationId,
        automationRunId: runId
      })
      if (!run) {
        throw new Error("Couldn't find automation or its run")
      }
      if (!run.executionEngineRunId) {
        throw new Error('No associated run found on the execution engine')
      }

      const setPlaintextHeaders = () => {
        res.setHeader('Content-Type', 'text/plain; charset=utf-8')
        res.setHeader('Cache-Control', 'no-cache')
      }

      try {
        let firstLine = true
        const logGenerator = getAutomationRunLogs({
          automationId: run.executionEngineAutomationId,
          automationRunId: run.executionEngineRunId,
          automationToken: run.token
        })
        for await (const line of logGenerator) {
          if (firstLine) {
            // Only do this now, so that if log retrieval failed defaultErrorHandler correctly returns JSON response
            setPlaintextHeaders()
            firstLine = false
          }
          res.write(line)
        }
      } catch (e) {
        if (e instanceof ExecutionEngineFailedResponseError) {
          if (e.response.statusMessage === 'LOG_MISSING_OR_NOT_READY') {
            setPlaintextHeaders()
            res.write('')
            res.end()
            return
          }
        }

        throw e
      }

      res.end()
    }
  )
}