package com.vgmlr.stave

import android.content.Context
import android.content.Intent
import java.util.Locale

data class StaveImport(val name: String, val time: String, val entries: List<StaveEntry>)

object StaveText {
    
    fun format(trip: StaveTrip, entries: List<StaveEntry>): String {
        val rows = entries.asReversed()

        val idx = rows.indices.map { "${it + 1}." }
        val time = rows.map { it.stavetime }
        val cost = rows.map { money(it.cost) }
        val cat = rows.map { it.label }

        val wIdx = idx.maxOfOrNull { it.length } ?: 0
        val wTime = time.maxOfOrNull { it.length } ?: 0
        val wCost = cost.maxOfOrNull { it.length } ?: 0
        val wCat = cat.maxOfOrNull { it.length } ?: 0

        return buildString {
            append("Stave: ").append(trip.name).append('\n')
            append("Total: ").append(money(rows.sumOf { it.cost })).append('\n')
            if (rows.isNotEmpty()) append('\n')

            rows.indices.forEach { i ->
                val line = buildString {
                    append(idx[i].padStart(wIdx)).append(GAP)
                    append(time[i].padEnd(wTime)).append(GAP)
                    append(cat[i].padEnd(wCat)).append(GAP)
                    append(cost[i].padStart(wCost)).append(GAP)
                    append(rows[i].location)
                }
                append(line.trimEnd()).append('\n')
            }
        }
    }

    fun fileName(trip: StaveTrip): String =
        "stave_${slug(trip.name)}_${StaveOTCClock.getFileNameTimestamp()}.tsv"

    // oldest first
    fun toTsv(trip: StaveTrip, entries: List<StaveEntry>): String = buildString {
        append(MAGIC).append('\t').append(FORMAT).append('\n')
        append(clean(trip.name)).append('\t').append(clean(trip.stavetime)).append('\n')
        append(TSV_HEAD).append('\n')
        entries.asReversed().forEach { e ->
            listOf(
                clean(e.stavetime),
                clean(e.category),
                String.format(Locale.US, "%.2f", e.cost),
                clean(e.note),
                clean(e.location),
                e.lat?.toString().orEmpty(),
                e.lng?.toString().orEmpty()
            ).joinTo(this, "\t")
            append('\n')
        }
    }

    fun parseTsv(text: String): StaveImport? {
        val lines = text.lineSequence().filter { it.isNotEmpty() }.toList()
        if (lines.size < 2 || lines[0] != "$MAGIC\t$FORMAT") return null
        val head = lines[1].split('\t')
        val entries = lines.drop(2).filterNot { it.startsWith("#") }.mapNotNull { line ->
            val f = line.split('\t')
            val cost = f.getOrNull(2)?.toDoubleOrNull()
            if (f.size < COLS || cost == null) null
            else StaveEntry(
                id = 0,
                tripId = 0,
                cost = cost,
                category = f[1],
                location = f[4],
                stavetime = f[0],
                lat = f[5].toDoubleOrNull(),
                lng = f[6].toDoubleOrNull(),
                note = f[3]
            )
        }
        return StaveImport(head[0], head.getOrElse(1) { "" }, entries)
    }

    private fun clean(s: String): String = s.replace(TAB_BREAK, " ")

    private fun slug(name: String): String =
        name.trim().replace(Regex("[^A-Za-z0-9]+"), "-").trim('-').ifBlank { "trip" }

    private const val GAP = "  "
    private const val MAGIC = "STAVE"
    private const val FORMAT = 1
    private const val COLS = 7
    private const val TSV_HEAD = "# time\tcategory\tcost\tnote\tlocation\tlat\tlng"
    private val TAB_BREAK = Regex("[\t\r\n]")
}

fun shareStave(context: Context, trip: StaveTrip, entries: List<StaveEntry>) {
    val send = Intent(Intent.ACTION_SEND).apply {
        type = "text/plain"
        putExtra(Intent.EXTRA_SUBJECT, trip.name)
        putExtra(Intent.EXTRA_TEXT, StaveText.format(trip, entries))
    }
    context.startActivity(Intent.createChooser(send, null))
}