// Copyright 2021 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package java

import (
	"strings"

	"android/soong/android"
	"android/soong/dexpreopt"

	"github.com/google/blueprint/pathtools"
)

func init() {
	RegisterDexpreoptCheckBuildComponents(android.InitRegistrationContext)
}

func RegisterDexpreoptCheckBuildComponents(ctx android.RegistrationContext) {
	ctx.RegisterSingletonModuleType("dexpreopt_systemserver_check", dexpreoptSystemserverCheckFactory)
}

// A build-time check to verify if all compilation artifacts of system server jars are installed
// into the system image. When the check fails, it means that dexpreopting is not working for some
// system server jars and needs to be fixed.
// This singleton module generates a list of the paths to the artifacts based on
// PRODUCT_SYSTEM_SERVER_JARS and PRODUCT_APEX_SYSTEM_SERVER_JARS, and passes it to Make via a
// variable. Make will then do the actual check.
// Currently, it only checks artifacts of modules defined in Soong. Artifacts of modules defined in
// Makefile are generated by a script generated by dexpreopt_gen, and their existence is unknown to
// Make and Ninja.
type dexpreoptSystemserverCheck struct {
	android.SingletonModuleBase

	// Mapping from the module name to the install paths to the compilation artifacts.
	artifactsByModuleName map[string][]string

	// The install paths to the compilation artifacts.
	artifacts []string
}

func dexpreoptSystemserverCheckFactory() android.SingletonModule {
	m := &dexpreoptSystemserverCheck{}
	m.artifactsByModuleName = make(map[string][]string)
	android.InitAndroidArchModule(m, android.DeviceSupported, android.MultilibCommon)
	return m
}

func getInstallPath(ctx android.ModuleContext, location string) android.InstallPath {
	return android.PathForModuleInPartitionInstall(
		ctx, "", strings.TrimPrefix(location, "/"))
}

func (m *dexpreoptSystemserverCheck) GenerateAndroidBuildActions(ctx android.ModuleContext) {
	global := dexpreopt.GetGlobalConfig(ctx)
	targets := ctx.Config().Targets[android.Android]

	// The check should be skipped on unbundled builds because system server jars are not preopted on
	// unbundled builds since the artifacts are installed into the system image, not the APEXes.
	if global.DisablePreopt || len(targets) == 0 || ctx.Config().UnbundledBuild() {
		return
	}

	systemServerJars := global.AllSystemServerJars(ctx)
	for _, jar := range systemServerJars.CopyOfJars() {
		dexLocation := dexpreopt.GetSystemServerDexLocation(ctx, global, jar)
		odexLocation := dexpreopt.ToOdexPath(dexLocation, targets[0].Arch.ArchType)
		odexPath := getInstallPath(ctx, odexLocation)
		vdexPath := getInstallPath(ctx, pathtools.ReplaceExtension(odexLocation, "vdex"))
		m.artifactsByModuleName[jar] = []string{odexPath.String(), vdexPath.String()}
	}
}

func (m *dexpreoptSystemserverCheck) GenerateSingletonBuildActions(ctx android.SingletonContext) {
	// Only keep modules defined in Soong.
	ctx.VisitAllModules(func(module android.Module) {
		if artifacts, ok := m.artifactsByModuleName[module.Name()]; ok {
			m.artifacts = append(m.artifacts, artifacts...)
		}
	})
}

func (m *dexpreoptSystemserverCheck) MakeVars(ctx android.MakeVarsContext) {
	ctx.Strict("DEXPREOPT_SYSTEMSERVER_ARTIFACTS", strings.Join(m.artifacts, " "))
}