import groovy.json.JsonSlurper

plugins {
    id 'org.gradle.toolchains.foojay-resolver-convention' version '1.0.0'
}

rootProject.name = 'ca-skeleton'

File repositoryRoot = settingsDir.parentFile.canonicalFile
File moduleRegistryFile = new File(settingsDir, 'config/architecture/modules.json')
if (!moduleRegistryFile.isFile()) {
    throw new GradleException("Missing module registry: ${moduleRegistryFile}")
}

def moduleRegistry = new JsonSlurper().parse(moduleRegistryFile)
if (!(moduleRegistry instanceof Map)) {
    throw new GradleException("Module registry root must be a JSON object: ${moduleRegistryFile}")
}
Set<String> expectedRootFields = ['runtime_compositions', 'modules'] as Set
if (moduleRegistry.keySet().collect { it as String }.toSet() != expectedRootFields) {
    throw new GradleException(
            "Module registry root fields must be exactly ${expectedRootFields}: ${moduleRegistryFile}")
}
if (!(moduleRegistry.modules instanceof List) || moduleRegistry.modules.isEmpty()) {
    throw new GradleException("Module registry has no modules: ${moduleRegistryFile}")
}
Set<String> expectedRuntimeCompositions = ['app-bootstrap', 'sample-portfolio'] as Set
if (!(moduleRegistry.runtime_compositions instanceof List) ||
        moduleRegistry.runtime_compositions.collect { it as String }.toSet() !=
                expectedRuntimeCompositions ||
        moduleRegistry.runtime_compositions.size() != expectedRuntimeCompositions.size()) {
    throw new GradleException(
            "Module registry runtime_compositions must be exactly ${expectedRuntimeCompositions}: " +
                    moduleRegistryFile)
}

int expectedModuleCount = 19
if (moduleRegistry.modules.size() != expectedModuleCount) {
    throw new GradleException(
            "Module registry must contain exactly ${expectedModuleCount} modules, " +
                    "but found ${moduleRegistry.modules.size()}: ${moduleRegistryFile}")
}

Set<String> moduleIds = new LinkedHashSet<>()
Set<String> gradlePaths = new LinkedHashSet<>()
Set<String> sourceDirectoryPaths = new LinkedHashSet<>()
String repositoryRootPrefix = repositoryRoot.path + File.separator

List<Map<String, Object>> validatedModules = moduleRegistry.modules.withIndex().collect { rawModule, index ->
    if (!(rawModule instanceof Map)) {
        throw new GradleException("Module registry entry ${index} must be a JSON object.")
    }

    Map<String, Object> module = rawModule as Map<String, Object>
    Set<String> expectedModuleFields = [
            'id',
            'gradle_path',
            'source_path',
            'allowed_dependencies',
            'runtime_memberships'
    ] as Set
    if (module.keySet().collect { it as String }.toSet() != expectedModuleFields) {
        throw new GradleException(
                "Module registry entry ${index} fields must be exactly ${expectedModuleFields}.")
    }
    ['id', 'gradle_path', 'source_path'].each { field ->
        if (!(module[field] instanceof String) || (module[field] as String).isBlank()) {
            throw new GradleException(
                    "Module registry entry ${index} needs a nonblank string '${field}'.")
        }
    }
    if (!(module.allowed_dependencies instanceof List)) {
        throw new GradleException(
                "Module registry entry '${module.id}' needs an 'allowed_dependencies' list.")
    }
    if (!(module.runtime_memberships instanceof List)) {
        throw new GradleException(
                "Module registry entry '${module.id}' needs a 'runtime_memberships' list.")
    }

    String id = module.id as String
    String gradlePath = module.gradle_path as String
    String sourcePath = module.source_path as String
    List<String> allowedDependencies = module.allowed_dependencies.withIndex().collect {
        dependencyId, dependencyIndex ->
            if (!(dependencyId instanceof String) || (dependencyId as String).isBlank()) {
                throw new GradleException(
                        "Module registry entry '${id}' has a non-string or blank allowed dependency " +
                                "at index ${dependencyIndex}.")
            }
            dependencyId as String
    }
    List<String> runtimeMemberships = module.runtime_memberships.withIndex().collect {
        membership, membershipIndex ->
            if (!(membership instanceof String) || (membership as String).isBlank()) {
                throw new GradleException(
                        "Module registry entry '${id}' has a non-string or blank runtime membership " +
                                "at index ${membershipIndex}.")
            }
            membership as String
    }
    if (runtimeMemberships.toSet().size() != runtimeMemberships.size()) {
        throw new GradleException(
                "Module registry entry '${id}' contains duplicate runtime memberships.")
    }
    Set<String> unknownRuntimeMemberships = runtimeMemberships.toSet() - expectedRuntimeCompositions
    if (!unknownRuntimeMemberships.isEmpty()) {
        throw new GradleException(
                "Module registry entry '${id}' references unknown runtime memberships " +
                        "${unknownRuntimeMemberships.toSorted()}.")
    }

    if (!moduleIds.add(id)) {
        throw new GradleException("Module registry contains duplicate module id '${id}'.")
    }
    if (!gradlePath.startsWith(':')) {
        throw new GradleException(
                "Module registry entry '${id}' has Gradle path '${gradlePath}' that does not start with ':'.")
    }
    if (!gradlePaths.add(gradlePath)) {
        throw new GradleException("Module registry contains duplicate Gradle path '${gradlePath}'.")
    }
    if (new File(sourcePath).isAbsolute()) {
        throw new GradleException(
                "Module registry entry '${id}' source path must be repository-root-relative: '${sourcePath}'.")
    }

    File sourceDirectory = new File(repositoryRoot, sourcePath).canonicalFile
    if (!sourceDirectory.path.startsWith(repositoryRootPrefix)) {
        throw new GradleException(
                "Module registry entry '${id}' source path escapes the repository root: '${sourcePath}'.")
    }
    if (!sourceDirectory.isDirectory()) {
        throw new GradleException(
                "Module registry entry '${id}' source path is not an existing directory: ${sourceDirectory}")
    }
    if (!sourceDirectoryPaths.add(sourceDirectory.path)) {
        throw new GradleException(
                "Module registry entry '${id}' resolves to duplicate or aliased canonical source directory: " +
                        "${sourceDirectory}")
    }

    [
            id                  : id,
            gradle_path         : gradlePath,
            source_directory    : sourceDirectory,
            allowed_dependencies: allowedDependencies,
            runtime_memberships : runtimeMemberships
    ]
}

expectedRuntimeCompositions.each { compositionId ->
    Map<String, Object> composition = validatedModules.find { it.id == compositionId }
    if (composition == null || !(composition.runtime_memberships as List).contains(compositionId)) {
        throw new GradleException(
                "Runtime composition '${compositionId}' must be registered and include itself in " +
                        'runtime_memberships.')
    }
}

validatedModules.each { module ->
    module.allowed_dependencies.each { dependencyId ->
        if (dependencyId == module.id) {
            throw new GradleException(
                    "Module registry entry '${module.id}' must not depend on itself.")
        }
        if (module.id != 'sample-portfolio' && dependencyId == 'sample-portfolio') {
            throw new GradleException(
                    "Production module registry entry '${module.id}' must not allow a dependency on " +
                            "'sample-portfolio'.")
        }
        if (!moduleIds.contains(dependencyId)) {
            throw new GradleException(
                    "Module registry entry '${module.id}' references unknown allowed dependency id " +
                            "'${dependencyId}'.")
        }
    }
}

validatedModules.each { module ->
    include module.gradle_path
    project(module.gradle_path).projectDir = module.source_directory
}