import {
  createContext,
  useCallback,
  useContext,
  useEffect,
  useMemo,
  useState,
} from 'react'
import { useSearchParams } from 'react-router-dom'
import { getInitiative } from '../api/initiatives.js'
import { getProject } from '../api/projects.js'
import { scopedPath } from '../utils/routes.js'

const ProgramScopeContext = createContext(null)

export function ProgramScopeProvider({ children }) {
  const [searchParams, setSearchParams] = useSearchParams()
  const initiativeId = searchParams.get('initiative') || ''
  const projectId = searchParams.get('project') || ''

  const [initiativeTitle, setInitiativeTitle] = useState('')
  const [projectTitle, setProjectTitle] = useState('')

  useEffect(() => {
    if (!initiativeId) {
      setInitiativeTitle('')
      return
    }
    let cancelled = false
    getInitiative(initiativeId)
      .then((data) => {
        if (!cancelled) setInitiativeTitle(data.title || '')
      })
      .catch(() => {
        if (!cancelled) setInitiativeTitle('')
      })
    return () => {
      cancelled = true
    }
  }, [initiativeId])

  useEffect(() => {
    if (!projectId) {
      setProjectTitle('')
      return
    }
    let cancelled = false
    getProject(projectId)
      .then((data) => {
        if (!cancelled) setProjectTitle(data.title || '')
      })
      .catch(() => {
        if (!cancelled) setProjectTitle('')
      })
    return () => {
      cancelled = true
    }
  }, [projectId])

  const setScope = useCallback(
    (next) => {
      const params = new URLSearchParams(searchParams)
      if ('initiativeId' in next) {
        if (next.initiativeId) params.set('initiative', next.initiativeId)
        else params.delete('initiative')
      }
      if ('projectId' in next) {
        if (next.projectId) params.set('project', next.projectId)
        else params.delete('project')
      }
      if (next.clearProject) params.delete('project')
      setSearchParams(params, { replace: true })
    },
    [searchParams, setSearchParams],
  )

  const clearScope = useCallback(() => {
    setSearchParams({}, { replace: true })
  }, [setSearchParams])

  const refreshInitiativeMeta = useCallback(() => {
    if (!initiativeId) return
    getInitiative(initiativeId)
      .then((data) => setInitiativeTitle(data.title || ''))
      .catch(() => setInitiativeTitle(''))
  }, [initiativeId])

  const applyFromInitiative = useCallback(
    (id, { keepProject = false } = {}) => {
      if (!id) return
      setScope({
        initiativeId: id,
        projectId: keepProject ? projectId : '',
        clearProject: !keepProject,
      })
    },
    [projectId, setScope],
  )

  const applyFromProject = useCallback(
    (project) => {
      if (!project?.initiative_id) return
      setScope({
        initiativeId: project.initiative_id,
        projectId: project.id,
      })
    },
    [setScope],
  )

  const applyFromAction = useCallback(
    (action) => {
      if (!action?.initiative_id) return
      setScope({
        initiativeId: action.initiative_id,
        projectId: action.project_id || '',
        clearProject: !action.project_id,
      })
    },
    [setScope],
  )

  const hrefWithScope = useCallback(
    (path) => scopedPath(path, { initiativeId, projectId }),
    [initiativeId, projectId],
  )

  const value = useMemo(
    () => ({
      initiativeId,
      projectId,
      initiativeTitle,
      projectTitle,
      setScope,
      clearScope,
      applyFromInitiative,
      applyFromProject,
      applyFromAction,
      hrefWithScope,
      refreshInitiativeMeta,
      hasScope: Boolean(initiativeId),
    }),
    [
      initiativeId,
      projectId,
      initiativeTitle,
      projectTitle,
      setScope,
      clearScope,
      applyFromInitiative,
      applyFromProject,
      applyFromAction,
      hrefWithScope,
      refreshInitiativeMeta,
    ],
  )

  return (
    <ProgramScopeContext.Provider value={value}>{children}</ProgramScopeContext.Provider>
  )
}

export function useProgramScope() {
  const ctx = useContext(ProgramScopeContext)
  if (!ctx) {
    throw new Error('useProgramScope must be used within ProgramScopeProvider')
  }
  return ctx
}

export function useOptionalProgramScope() {
  return useContext(ProgramScopeContext)
}