import { useState } from 'react'
import { analysisApi } from '../services/api'
import type { ChangeDetectionSummary, DatasetCreateResponse } from '../types'
import { formatError } from '../lib/formatError'

interface ChangeDetectionWorkflowOptions {
  selectedProjectId: string | null
  availableVectorDatasets: DatasetCreateResponse[]
  loadDatasetJobs: (projectId: string, datasetId: string) => Promise<void>
}

export function useChangeDetectionWorkflow({
  selectedProjectId,
  availableVectorDatasets,
  loadDatasetJobs,
}: ChangeDetectionWorkflowOptions) {
  const [changeSourceDatasetId, setChangeSourceDatasetId] = useState('')
  const [changeTargetDatasetId, setChangeTargetDatasetId] = useState('')
  const [changeIouThreshold, setChangeIouThreshold] = useState(0.8)
  const [changeIncludeUnchanged, setChangeIncludeUnchanged] = useState(true)
  const [runningChangeDetection, setRunningChangeDetection] = useState(false)
  const [changeDetectionResult, setChangeDetectionResult] = useState<ChangeDetectionSummary | null>(null)
  const [changeDetectionError, setChangeDetectionError] = useState<string | null>(null)

  const runChangeDetection = async () => {
    const sourceDatasetId = changeSourceDatasetId || availableVectorDatasets[0]?.id
    const targetDatasetId =
      changeTargetDatasetId || availableVectorDatasets.find((dataset) => dataset.id !== sourceDatasetId)?.id
    if (!sourceDatasetId || !targetDatasetId) {
      setChangeDetectionError('Select two vector datasets')
      return
    }
    if (sourceDatasetId === targetDatasetId) {
      setChangeDetectionError('Source and target datasets must differ')
      return
    }
    if (changeIouThreshold < 0 || changeIouThreshold > 1) {
      setChangeDetectionError('IoU threshold must be between 0 and 1')
      return
    }
    setChangeDetectionError(null)
    setChangeDetectionResult(null)
    setRunningChangeDetection(true)
    try {
      const job = await analysisApi.runChangeDetection({
        source_dataset_id: sourceDatasetId,
        target_dataset_id: targetDatasetId,
        iou_threshold: changeIouThreshold,
        include_unchanged: changeIncludeUnchanged,
      })
      if (job.status !== 'success') {
        throw new Error(job.error_message || 'Change detection job failed')
      }
      if (!job.result_json) {
        throw new Error('Change detection completed without result payload')
      }
      setChangeSourceDatasetId(sourceDatasetId)
      setChangeTargetDatasetId(targetDatasetId)
      setChangeDetectionResult(job.result_json)
      if (selectedProjectId) {
        await loadDatasetJobs(selectedProjectId, sourceDatasetId)
      }
    } catch (error) {
      setChangeDetectionError(formatError(error, 'Change detection failed'))
    } finally {
      setRunningChangeDetection(false)
    }
  }

  return {
    changeSourceDatasetId,
    changeTargetDatasetId,
    changeIouThreshold,
    changeIncludeUnchanged,
    runningChangeDetection,
    changeDetectionResult,
    changeDetectionError,
    runChangeDetection,
    setChangeSourceDatasetId,
    setChangeTargetDatasetId,
    setChangeIouThreshold,
    setChangeIncludeUnchanged,
  }
}