package com.peachpasswords.backup

import java.io.File
import javax.xml.parsers.DocumentBuilderFactory
import org.junit.Assert.assertTrue
import org.junit.Test

/** Every declared SharedPreferences file must be excluded from both transfer paths. */
class BackupRulesCoverageTest {
    @Test
    fun every_shared_preferences_filename_is_excluded_from_both_rule_files() {
        val sourceRoot = projectFile("app/src/main/java")
        val preferences = sourceRoot.walkTopDown()
            .filter { it.isFile && it.extension == "kt" }
            .flatMap { file -> PREFERENCE_DECLARATION.findAll(file.readText()).map { it.groupValues[1] } }
            .map { "$it.xml" }
            .toSet()
        assertTrue("no SharedPreferences declarations were found", preferences.isNotEmpty())

        val backup = excludedPaths(projectFile("app/src/main/res/xml/backup_rules.xml"))
        val extraction = excludedPaths(projectFile("app/src/main/res/xml/data_extraction_rules.xml"))
        preferences.forEach { filename ->
            assertTrue("$filename is missing from backup_rules.xml", filename in backup)
            assertTrue("$filename is missing from data_extraction_rules.xml", filename in extraction)
        }
    }

    private fun excludedPaths(file: File): Set<String> {
        val document = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(file)
        return (0 until document.getElementsByTagName("exclude").length)
            .map { index -> document.getElementsByTagName("exclude").item(index).attributes.getNamedItem("path").nodeValue }
            .toSet()
    }

    private fun projectFile(relativePath: String): File =
        File(relativePath).takeIf { it.exists() } ?: File("../$relativePath")

    private companion object {
        val PREFERENCE_DECLARATION = Regex(
            "(?m)^\\s*(?:private\\s+|internal\\s+|public\\s+)?(?:const\\s+)?val\\s+\\w*PREFS\\w*\\s*=\\s*\"([^\"]+)\"",
        )
    }
}