import org.w3c.dom.Element
import javax.xml.parsers.DocumentBuilderFactory

plugins {
    alias(libs.plugins.kotlinMultiplatform)
    alias(libs.plugins.composeMultiplatform)
    alias(libs.plugins.composeCompiler)
}

// webHtmlApp can't use moko-resources' Compose integration (stringResource()) without pulling
// in compose.foundation/ui transitively - exactly what this module exists to avoid (see
// AGENTS.md's "Module layout"). Generating a plain Strings.kt from the same strings.xml moko
// reads keeps that file as the single source of truth without a manually maintained, silently
// driftable duplicate. Only covers the base (English) locale - see AGENTS.md.
val stringsXmlFile = rootProject.file("shared/src/commonMain/moko-resources/base/strings.xml")

val generateStrings by tasks.registering {
    val outputDir = layout.buildDirectory.dir("generated/strings")
    // Captured as a plain local (rather than read from the doLast closure directly) so the task
    // action doesn't hold a reference to the build script object itself, which the configuration
    // cache refuses to serialize.
    val xmlFile = stringsXmlFile
    inputs.file(xmlFile)
    outputs.dir(outputDir)

    doLast {
        val document = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(xmlFile)
        val stringNodes = document.getElementsByTagName("string")
        val placeholderPattern = Regex("""%(\d+)\$([sd])""")

        fun String.toCamelCase(): String = split("_").mapIndexed { index, word ->
            if (index == 0) word else word.replaceFirstChar { it.uppercase() }
        }.joinToString("")

        val source = buildString {
            appendLine("// GENERATED FILE - do not edit directly.")
            appendLine("// Regenerated by :webHtmlApp:generateStrings from")
            appendLine("// shared/src/commonMain/moko-resources/base/strings.xml - edit that file instead.")
            appendLine("package xyz.tyiu.satsprice")
            appendLine()
            appendLine("object Strings {")
            for (i in 0 until stringNodes.length) {
                val element = stringNodes.item(i) as Element
                val propertyName = element.getAttribute("name").toCamelCase()
                // moko/Android string-resource XML escapes a literal apostrophe as \' inside the
                // (unquoted) text content - unescape that before anything else so it doesn't get
                // mistaken for a Kotlin escape sequence below.
                val rawValue = element.textContent.replace("\\'", "'")

                val placeholders = placeholderPattern.findAll(rawValue)
                    .map { it.groupValues[1].toInt() to it.groupValues[2] }
                    .distinct()
                    .sortedBy { it.first }
                    .toList()

                // Swap each %N$s/%N$d placeholder for a control-character sentinel first, so the
                // literal '$' in "%1$s" itself doesn't get caught by the blanket '$' -> "\$"
                // escaping below - then escape, then turn the sentinels into "${argN}".
                var withSentinels = rawValue
                for ((index, _) in placeholders) {
                    withSentinels = withSentinels.replace(Regex("""%$index\$[sd]"""), "
$index
")
                }
                val escaped = withSentinels
                    .replace("\\", "\\\\")
                    .replace("\"", "\\\"")
                    .replace("$", "\\$")
                var templateBody = escaped
                for ((index, _) in placeholders) {
                    templateBody = templateBody.replace("
$index
", "\${arg$index}")
                }

                if (placeholders.isEmpty()) {
                    appendLine("    const val $propertyName: String = \"$templateBody\"")
                } else {
                    val params = placeholders.joinToString(", ") { (index, type) ->
                        "arg$index: ${if (type == "d") "Int" else "String"}"
                    }
                    appendLine("    fun $propertyName($params): String = \"$templateBody\"")
                }
            }
            appendLine("}")
        }

        val outputFile = outputDir.get().file("xyz/tyiu/satsprice/Strings.kt").asFile
        outputFile.parentFile.mkdirs()
        outputFile.writeText(source)
    }
}

// Compose HTML (org.jetbrains.compose.html:html-core) only publishes js and jvm target
// variants as of Compose Multiplatform 1.11.1 - no wasmJs artifact exists yet, unlike the
// Skia-based Compose Multiplatform UI toolkit webApp uses (which targets both). So this
// comparison module is js-only for now.
kotlin {
    js {
        browser()
        binaries.executable()
    }

    sourceSets {
        commonMain {
            kotlin.srcDir(generateStrings)
            dependencies {
                implementation(project(":shared"))

                implementation(libs.compose.runtime)
                implementation(libs.compose.html.core)
            }
        }
    }
}