package com.tt.honeyDue.models

import kotlinx.serialization.encodeToString
import kotlinx.serialization.json.Json

/**
 * Shared encoder/decoder for `.honeydue` payloads across Android and iOS.
 *
 * This keeps package JSON shape in one place while each platform owns
 * native share-sheet presentation details.
 */
object HoneyDueShareCodec {
    private val json = Json {
        prettyPrint = true
        ignoreUnknownKeys = true
        encodeDefaults = true
    }

    fun encodeContractorPackage(contractor: Contractor, exportedBy: String? = null): String {
        return encodeSharedContractor(contractor.toSharedContractor(exportedBy))
    }

    fun encodeSharedContractor(sharedContractor: SharedContractor): String {
        return json.encodeToString(SharedContractor.serializer(), sharedContractor)
    }

    fun encodeSharedResidence(sharedResidence: SharedResidence): String {
        return json.encodeToString(SharedResidence.serializer(), sharedResidence)
    }

    fun decodeSharedContractorOrNull(jsonContent: String): SharedContractor? {
        return try {
            json.decodeFromString(SharedContractor.serializer(), jsonContent)
        } catch (_: Exception) {
            null
        }
    }

    fun decodeSharedResidenceOrNull(jsonContent: String): SharedResidence? {
        return try {
            json.decodeFromString(SharedResidence.serializer(), jsonContent)
        } catch (_: Exception) {
            null
        }
    }

    fun createContractorImportRequestOrNull(
        jsonContent: String,
        availableSpecialties: List<ContractorSpecialty>
    ): ContractorCreateRequest? {
        val shared = decodeSharedContractorOrNull(jsonContent) ?: return null
        val specialtyIds = shared.resolveSpecialtyIds(availableSpecialties)
        return shared.toCreateRequest(specialtyIds)
    }

    fun extractResidenceShareCodeOrNull(jsonContent: String): String? {
        return decodeSharedResidenceOrNull(jsonContent)?.shareCode
    }

    /**
     * Build a filesystem-safe package filename with `.honeydue` extension.
     *
     * Strips only the characters that are actually unsafe on iOS / Android
     * filesystems (`/`, `\`, `:`, `*`, `?`, `"`, `<`, `>`, `|`, control
     * chars). Spaces and apostrophes are kept intact so the recipient sees
     * the original residence / contractor name in the iOS QuickLook title
     * bar — gitea#7 called out the previous behaviour rendering
     * "The_Tartt's" instead of "The Tartt's". Internal whitespace is
     * collapsed to single spaces and trimmed; falls back to "honeyDue" if
     * the input is blank after sanitising.
     */
    fun safeShareFileName(displayName: String): String {
        val safeName = displayName
            // Keep whitespace through the filter so adjacent space+tab
            // sequences survive to the regex-collapse step below. Drop
            // only non-whitespace control chars (NUL etc.) plus the
            // explicit filesystem-unsafe set.
            .filter { it !in UNSAFE_FILENAME_CHARS && (it.isWhitespace() || !it.isISOControl()) }
            .replace(Regex("\\s+"), " ")
            .trim()
            .take(50)
            .ifBlank { "honeyDue" }
        return "$safeName.honeydue"
    }

    private val UNSAFE_FILENAME_CHARS = setOf('/', '\\', ':', '*', '?', '"', '<', '>', '|')
}