setup.gradle

def renameConfig = [
        templateName  : "template",
        templateAppId : "template.app.id",
        newPackage    : "domain.yourname.app",
        newProjectName: "Your Project",
]

task renameAppPackage(type: Copy) {
    description "Renames the template package in the app module."
    group null

    def newPackageAsDirectory = renameConfig.newPackage.replaceAll("\\.", "/")
    def startingDirectory = "${rootDir}/app/src/main/java/${renameConfig.templateName}"
    def endingDirectory = "${rootDir}/app/src/main/java/${newPackageAsDirectory}"

    from(startingDirectory)
    into(endingDirectory)

    // Replace package statements
    filter { line ->
        line.replaceAll(
                "package ${renameConfig.templateName}",
                "package ${renameConfig.newPackage}"
        )
    }

    // Replace import statements
    filter { line ->
        line.replaceAll(
                "import ${renameConfig.templateName}",
                "import ${renameConfig.newPackage}"
        )
    }

    doLast {
        delete(startingDirectory)

        ("git add $endingDirectory").execute()
    }
}

task replacePackageInManifest {
    description "Replaces references to template in AndroidManifest.xml file."
    group null

    doLast {
        def file = new File("${rootDir}/app/src/main/AndroidManifest.xml")

        // Replace package
        file.text = file.text.replaceAll(
                "package=\"${renameConfig.templateName}\"",
                "package=\"${renameConfig.newPackage}\"",
        )

        // Replace MainActivity reference
        file.text = file.text.replaceAll(
                "${renameConfig.templateName}.MainActivity",
                "${renameConfig.newPackage}.MainActivity",
        )
    }
}

task replaceApplicationId {
    description "Replaces application ID in app/build.gradle file."
    group null

    doLast {
        def file = new File("${rootDir}/app/build.gradle")

        file.text = file.text.replaceAll(
                "applicationId \"${renameConfig.templateAppId}\"",
                "applicationId \"${renameConfig.newPackage}\"",
        )
    }
}

task replaceProjectName {
    description "Replaces project name in settings.gradle file."
    group null

    doLast {
        def file = new File("${rootDir}/settings.gradle")

        file.text = file.text.replaceAll(
                "rootProject.name = \"${renameConfig.templateName}\"",
                "rootProject.name = \"${renameConfig.newProjectName}\"",
        )
    }
}

task replaceAppName {
    description "Replaces app name in strings.xml file."
    group null

    doLast {
        def file = new File("${rootDir}/app/src/main/res/values/strings.xml")

        file.text = file.text.replaceAll(
                "<string name=\"app_name\">${renameConfig.templateName}</string>",
                "<string name=\"app_name\">${renameConfig.newProjectName}</string>",
        )
    }
}

task renameTemplate {
    description "Runs all of the necessary template setup tasks based on the renameConfig."
    group "Template Setup"

    dependsOn(
            renameAppPackage,
            replacePackageInManifest,
            replaceApplicationId,
            replaceProjectName,
            replaceAppName,
    )
}