import { defineStore } from 'pinia'
import { ref, computed } from 'vue'
import workoutLibraryApi from '@/services/workoutLibraryApi'

export const useWorkoutLibraryStore = defineStore('workoutLibrary', () => {
  const workouts = ref([])
  const userWorkouts = ref([])
  const favorites = ref([])
  const currentWorkout = ref(null)
  const currentIntervals = ref([])
  const loading = ref(false)
  const error = ref(null)

  const filters = ref({
    category: '',
    duration_min: null,
    duration_max: null,
    intensity_min: null,
    intensity_max: null,
    search: ''
  })

  const pagination = ref({
    page: 1,
    limit: 20,
    total: 0
  })

  const favoriteIds = computed(() => new Set(favorites.value.map(f => f.id)))

  const isFavorited = (workoutId) => favoriteIds.value.has(workoutId)

  async function fetchWorkouts() {
    loading.value = true
    error.value = null

    try {
      const params = {
        page: pagination.value.page,
        limit: pagination.value.limit,
        ...Object.fromEntries(
          Object.entries(filters.value).filter(([_, v]) => v !== '' && v !== null)
        )
      }
      const data = await workoutLibraryApi.getWorkouts(params)
      workouts.value = data.workouts || []
      pagination.value.total = data.total || 0
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to fetch workouts'
    } finally {
      loading.value = false
    }
  }

  async function fetchWorkout(workoutId) {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.getWorkout(workoutId)
      currentWorkout.value = data.workout || data
      return currentWorkout.value
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to fetch workout'
      throw err
    } finally {
      loading.value = false
    }
  }

  async function fetchWorkoutIntervals(workoutId) {
    try {
      const data = await workoutLibraryApi.getWorkoutIntervals(workoutId)
      currentIntervals.value = data.intervals || []
      return currentIntervals.value
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to fetch intervals'
      throw err
    }
  }

  async function fetchUserWorkouts() {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.getUserWorkouts()
      userWorkouts.value = data.workouts || []
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to fetch your workouts'
    } finally {
      loading.value = false
    }
  }

  async function createWorkout(workout) {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.createWorkout(workout)
      userWorkouts.value.unshift(data.workout || data)
      return data.workout || data
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to create workout'
      throw err
    } finally {
      loading.value = false
    }
  }

  async function updateWorkout(workoutId, workout) {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.updateWorkout(workoutId, workout)
      const index = userWorkouts.value.findIndex(w => w.id === workoutId)
      if (index !== -1) {
        userWorkouts.value[index] = data.workout || data
      }
      return data.workout || data
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to update workout'
      throw err
    } finally {
      loading.value = false
    }
  }

  async function deleteWorkout(workoutId) {
    loading.value = true
    error.value = null

    try {
      await workoutLibraryApi.deleteWorkout(workoutId)
      userWorkouts.value = userWorkouts.value.filter(w => w.id !== workoutId)
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to delete workout'
      throw err
    } finally {
      loading.value = false
    }
  }

  async function publishWorkout(workoutId) {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.publishWorkout(workoutId)
      const index = userWorkouts.value.findIndex(w => w.id === workoutId)
      if (index !== -1) {
        userWorkouts.value[index].is_public = true
      }
      return data
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to publish workout'
      throw err
    } finally {
      loading.value = false
    }
  }

  async function fetchFavorites() {
    loading.value = true
    error.value = null

    try {
      const data = await workoutLibraryApi.getFavorites()
      favorites.value = data.favorites || data.workouts || []
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to fetch favorites'
    } finally {
      loading.value = false
    }
  }

  async function toggleFavorite(workoutId) {
    try {
      if (isFavorited(workoutId)) {
        await workoutLibraryApi.removeFavorite(workoutId)
        favorites.value = favorites.value.filter(f => f.id !== workoutId)
      } else {
        await workoutLibraryApi.addFavorite(workoutId)
        const workout = workouts.value.find(w => w.id === workoutId) || currentWorkout.value
        if (workout) {
          favorites.value.push(workout)
        }
      }
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to update favorite'
      throw err
    }
  }

  async function recordUsage(workoutId) {
    try {
      await workoutLibraryApi.recordUsage(workoutId)
    } catch (err) {
      console.error('Failed to record usage:', err)
    }
  }

  async function rateWorkout(workoutId, rating) {
    try {
      const data = await workoutLibraryApi.rateWorkout(workoutId, rating)
      if (currentWorkout.value && currentWorkout.value.id === workoutId) {
        currentWorkout.value.average_rating = data.average_rating
        currentWorkout.value.rating_count = data.rating_count
        currentWorkout.value.user_rating = rating
      }
      return data
    } catch (err) {
      error.value = err.response?.data?.error || 'Failed to rate workout'
      throw err
    }
  }

  function setFilters(newFilters) {
    filters.value = { ...filters.value, ...newFilters }
    pagination.value.page = 1
  }

  function clearFilters() {
    filters.value = {
      category: '',
      duration_min: null,
      duration_max: null,
      intensity_min: null,
      intensity_max: null,
      search: ''
    }
    pagination.value.page = 1
  }

  function setPage(page) {
    pagination.value.page = page
  }

  return {
    workouts,
    userWorkouts,
    favorites,
    currentWorkout,
    currentIntervals,
    loading,
    error,
    filters,
    pagination,
    favoriteIds,
    isFavorited,
    fetchWorkouts,
    fetchWorkout,
    fetchWorkoutIntervals,
    fetchUserWorkouts,
    createWorkout,
    updateWorkout,
    deleteWorkout,
    publishWorkout,
    fetchFavorites,
    toggleFavorite,
    recordUsage,
    rateWorkout,
    setFilters,
    clearFilters,
    setPage
  }
})