import { Controller } from '@hotwired/stimulus'

export default class extends Controller {

    static targets = ['mount', 'error', 'message', 'resetButton', 'day', 'dateFrom', 'dateTo', 'submit']

    static values = {
        hotelCode: String,
        selectedFrom: String,
        selectedTo: String,
        calendarRefreshUrl: String,
    }

    connect() {
        this.startDate = null
        this.endDate = null
        this.sessionRestored = false

        // Re-apply highlights after every HTMX month swap (navigation or initial load).
        this.mountTarget.addEventListener('htmx:afterSwap', () => requestAnimationFrame(() => this.initAfterLoad()))
        this.mountTarget.addEventListener('htmx:responseError', () => this.showError())
    }

    initAfterLoad() {
        // Restore from session values exactly once on the first swap.
        if (!this.sessionRestored) {
            this.sessionRestored = true
            const from = this.selectedFromValue
            const to = this.selectedToValue
            if (from && to) {
                this.startDate = from
                this.endDate = to
                if (this.hasResetButtonTarget) this.resetButtonTarget.classList.remove('hidden')
            }
        }
        this.updateDisplay()
    }

    selectDate(event) {
        const btn = event.currentTarget
        btn.blur()
        const date = btn.dataset.date
        const status = btn.dataset.status

        if (!status || status === 'blocked' || status === 'past') return

        if (this.startDate && this.endDate) {
            this.resetSelection()
        }

        if (!this.startDate) {
            if (status === 'checkout-only') {
                this.showMessage('Bitte wähle einen Anreisetag.')
                return
            }
            this.startDate = date
            this.endDate = null
            this.updateDisplay()
            this.showMessage('Bitte wähle das Abreisedatum.')
            return
        }

        if (date === this.startDate) {
            this.resetSelection()
            return
        }

        const [from, to] = date < this.startDate ? [date, this.startDate] : [this.startDate, date]

        if (this.hasBlockedInRange(from, to)) {
            this.resetSelection()
            this.showMessage('Dieser Zeitraum enthält nicht verfügbare Daten.')
            return
        }

        const startBtn = this.dayTargets.find(b => b.dataset.date === from)
        const minNights = parseInt(startBtn?.dataset.minNights) || 0
        const nights = (new Date(to) - new Date(from)) / 86400000

        if (minNights > 0 && nights < minNights) {
            this.showMessage(`Weniger als ${minNights} Nächte nur auf Anfrage.`)
        } else {
            this.hideMessage()
        }

        this.startDate = from
        this.endDate = to
        this.updateDisplay()
        this.activateSubmit(from, to)
        this.saveAndRefreshSummary(from, to)
        this.dispatch('range-select', { detail: { dateFrom: from, dateTo: to } })
    }

    hasBlockedInRange(from, to) {
        for (const btn of this.dayTargets) {
            const d = btn.dataset.date
            const s = btn.dataset.status
            if (d >= from && d < to && (s === 'blocked' || s === 'past' || s === 'checkout-only')) return true
        }
        return false
    }

    updateDisplay() {
        for (const btn of this.dayTargets) {
            const d = btn.dataset.date
            btn.classList.remove('pc-day--pending-start', 'pc-day--selected-start', 'pc-day--selected-end', 'pc-day--in-range')
            if (!this.startDate) continue
            if (d === this.startDate) {
                btn.classList.add(this.endDate ? 'pc-day--selected-start' : 'pc-day--pending-start')
            } else if (this.endDate) {
                if (d === this.endDate) btn.classList.add('pc-day--selected-end')
                else if (d > this.startDate && d < this.endDate) btn.classList.add('pc-day--in-range')
            }
        }
    }

    activateSubmit(dateFrom, dateTo) {
        if (this.hasDateFromTarget) this.dateFromTarget.value = dateFrom
        if (this.hasDateToTarget) this.dateToTarget.value = dateTo
        if (this.hasSubmitTarget) {
            this.submitTarget.disabled = false
            this.submitTarget.classList.remove('opacity-50', 'cursor-not-allowed', 'pointer-events-none')
        }
        if (this.hasResetButtonTarget) this.resetButtonTarget.classList.remove('hidden')
    }

    resetSelection() {
        this.startDate = null
        this.endDate = null
        this.updateDisplay()
        this.hideMessage()
        if (this.hasDateFromTarget) this.dateFromTarget.value = ''
        if (this.hasDateToTarget) this.dateToTarget.value = ''
        if (this.hasSubmitTarget) {
            this.submitTarget.disabled = true
            this.submitTarget.classList.add('opacity-50', 'cursor-not-allowed', 'pointer-events-none')
        }
        if (this.hasResetButtonTarget) this.resetButtonTarget.classList.add('hidden')
        this.saveAndRefreshSummary()
    }

    reset() {
        this.resetSelection()
    }

    saveAndRefreshSummary(dateFrom = '', dateTo = '') {
        if (!this.hasCalendarRefreshUrlValue) return
        htmx.ajax('POST', this.calendarRefreshUrlValue, {
            values: { date_from: dateFrom, date_to: dateTo },
            swap: 'none',
            target: this.element,
        })
    }

    showMessage(text) {
        if (this.hasMessageTarget) this.messageTarget.textContent = text
    }

    hideMessage() {
        if (this.hasMessageTarget) this.messageTarget.textContent = ''
    }

    showError() {
        if (this.hasErrorTarget) this.errorTarget.classList.remove('hidden')
    }
}