//go:build mage

package main

// SPDX-License-Identifier: GPL-3.0-or-later

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"runtime"

	"github.com/magefile/mage/mg"
	"github.com/magefile/mage/sh"
	"github.com/magefile/mage/target"
)

const (
	goPkg = "projects.blender.org/studio/flamenco"
)

var (
	// The directory that will contain the built webapp files, and some other
	// files that will be served as static files by the Flamenco Manager web
	// server.
	webStatic = filepath.Join("web", "static")
)

// Build Flamenco Manager and Flamenco Worker, including the webapp and the add-on
func Build() {
	mg.Deps(FlamencoManager, FlamencoWorker)
}

// BuildOptimized uses caching and parallelization for faster builds
func BuildOptimized() error {
	return BuildOptimizedWithContext(context.Background())
}

// BuildOptimizedWithContext builds with caching and parallelization
func BuildOptimizedWithContext(ctx context.Context) error {
	cache := NewBuildCache()
	
	// Warm cache and check what needs building
	if err := WarmBuildCache(cache); err != nil {
		fmt.Printf("Warning: Failed to warm build cache: %v\n", err)
	}

	// Define build tasks with dependencies
	tasks := []*BuildTask{
		CreateGenerateTask("generate-go", []string{}, func() error {
			return buildOptimizedGenerateGo(cache)
		}),
		CreateGenerateTask("generate-py", []string{}, func() error {
			return buildOptimizedGeneratePy(cache)
		}),
		CreateGenerateTask("generate-js", []string{}, func() error {
			return buildOptimizedGenerateJS(cache)
		}),
		CreateWebappTask("webapp-static", []string{"generate-js"}, func() error {
			return buildOptimizedWebappStatic(cache)
		}),
		CreateBuildTask("manager", []string{"generate-go", "webapp-static"}, func() error {
			return buildOptimizedManager(cache)
		}),
		CreateBuildTask("worker", []string{"generate-go"}, func() error {
			return buildOptimizedWorker(cache)
		}),
	}

	// Determine optimal concurrency
	maxConcurrency := runtime.NumCPU()
	if maxConcurrency > 4 {
		maxConcurrency = 4 // Reasonable limit for build tasks
	}
	
	builder := NewParallelBuilder(maxConcurrency)
	return builder.ExecuteParallel(ctx, tasks)
}

// BuildIncremental performs incremental build with caching
func BuildIncremental() error {
	cache := NewBuildCache()
	
	fmt.Println("Build: Starting incremental build with caching")
	
	// Check and build each component incrementally
	if err := buildIncrementalGenerate(cache); err != nil {
		return err
	}
	
	if err := buildIncrementalWebapp(cache); err != nil {
		return err
	}
	
	if err := buildIncrementalBinaries(cache); err != nil {
		return err
	}
	
	fmt.Println("Build: Incremental build completed successfully")
	return nil
}

// Build Flamenco Manager with the webapp and add-on ZIP embedded
func FlamencoManager() error {
	mg.Deps(WebappStatic)
	mg.Deps(flamencoManager)
	return nil
}

// Only build the Flamenco Manager executable, do not rebuild the webapp
func FlamencoManagerWithoutWebapp() error {
	mg.Deps(flamencoManager)
	return nil
}

// Build the Flamenco Manager executable with race condition checker enabled, do not rebuild the webapp
func FlamencoManagerRace() error {
	return build("./cmd/flamenco-manager", "-race")
}

func flamencoManager() error {
	return build("./cmd/flamenco-manager")
}

// Build the Flamenco Worker executable
func FlamencoWorker() error {
	return build("./cmd/flamenco-worker")
}

// Build the webapp as static files that can be served
func WebappStatic() error {
	runInstall, err := target.Dir("web/app/node_modules")
	if err != nil {
		return err
	}
	if runInstall {
		mg.SerialDeps(InstallDepsWebapp)
	}
	if err := cleanWebappStatic(); err != nil {
		return err
	}

	env := map[string]string{
		"MSYS2_ARG_CONV_EXCL": "*",
	}

	// When changing the base URL, also update the line
	// e.GET("/app/*", echo.WrapHandler(webAppHandler))
	// in `cmd/flamenco-manager/main.go`
	err = sh.RunWithV(env,
		"yarn",
		"--cwd", "web/app",
		"build",
		"--outDir", "../static",
		"--base=/app/",
		"--logLevel", "warn",
		// For debugging you can add:
		// "--minify", "false",
	)
	if err != nil {
		return err
	}

	fmt.Printf("Web app has been installed into %s\n", webStatic)

	// Build the add-on ZIP as it's part of the static web files.
	zipPath := filepath.Join(webStatic, "flamenco-addon.zip")
	return packAddon(zipPath)
}

func build(exePackage string, extraArgs ...string) error {
	flags, err := buildFlags()
	if err != nil {
		return err
	}

	args := []string{"build", "-v"}
	args = append(args, flags...)
	args = append(args, extraArgs...)
	args = append(args, exePackage)
	return sh.RunV(mg.GoCmd(), args...)
}

func buildFlags() ([]string, error) {
	hash, err := gitHash()
	if err != nil {
		return nil, err
	}

	ldflags := os.Getenv("LDFLAGS") +
		fmt.Sprintf(" -X %s/internal/appinfo.ApplicationVersion=%s", goPkg, version) +
		fmt.Sprintf(" -X %s/internal/appinfo.ApplicationGitHash=%s", goPkg, hash) +
		fmt.Sprintf(" -X %s/internal/appinfo.ReleaseCycle=%s", goPkg, releaseCycle)

	flags := []string{
		"-ldflags=" + ldflags,
	}
	return flags, nil
}

// Optimized build functions with caching

// buildOptimizedGenerateGo generates Go code with caching
func buildOptimizedGenerateGo(cache *BuildCache) error {
	sources := []string{
		"pkg/api/flamenco-openapi.yaml",
		"pkg/api/*.gen.go",
		"internal/**/*.go",
	}
	outputs := []string{
		"pkg/api/openapi_client.gen.go",
		"pkg/api/openapi_server.gen.go",
		"pkg/api/openapi_spec.gen.go",
		"pkg/api/openapi_types.gen.go",
	}
	
	needsBuild, err := cache.NeedsBuild("generate-go", sources, []string{}, outputs)
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: Go code generation is up to date")
		return cache.RestoreFromCache("generate-go", outputs)
	}
	
	fmt.Println("Cache: Generating Go code")
	if err := GenerateGo(context.Background()); err != nil {
		return err
	}
	
	// Record successful build and cache artifacts
	if err := cache.RecordBuild("generate-go", sources, []string{}, outputs); err != nil {
		return err
	}
	return cache.CopyToCache("generate-go", outputs)
}

// buildOptimizedGeneratePy generates Python code with caching
func buildOptimizedGeneratePy(cache *BuildCache) error {
	sources := []string{
		"pkg/api/flamenco-openapi.yaml",
		"addon/openapi-generator-cli.jar",
	}
	outputs := []string{
		"addon/flamenco/manager/",
	}
	
	needsBuild, err := cache.NeedsBuild("generate-py", sources, []string{}, outputs)
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: Python code generation is up to date")
		return nil // Directory outputs are harder to cache/restore
	}
	
	fmt.Println("Cache: Generating Python code")
	return GeneratePy()
}

// buildOptimizedGenerateJS generates JavaScript code with caching
func buildOptimizedGenerateJS(cache *BuildCache) error {
	sources := []string{
		"pkg/api/flamenco-openapi.yaml",
		"addon/openapi-generator-cli.jar",
	}
	outputs := []string{
		"web/app/src/manager-api/",
	}
	
	needsBuild, err := cache.NeedsBuild("generate-js", sources, []string{}, outputs)
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: JavaScript code generation is up to date")
		return nil // Directory outputs are harder to cache/restore
	}
	
	fmt.Println("Cache: Generating JavaScript code")
	return GenerateJS()
}

// buildOptimizedWebappStatic builds webapp with caching
func buildOptimizedWebappStatic(cache *BuildCache) error {
	sources := []string{
		"web/app/**/*.ts",
		"web/app/**/*.vue",
		"web/app/**/*.js",
		"web/app/package.json",
		"web/app/yarn.lock",
		"web/app/src/manager-api/**/*.js",
	}
	needsBuild, err := cache.NeedsBuild("webapp-static", sources, []string{"generate-js"}, []string{webStatic})
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: Webapp static files are up to date")
		return nil // Static directory is the output
	}
	
	fmt.Println("Cache: Building webapp static files")
	if err := WebappStatic(); err != nil {
		return err
	}
	
	// Record successful build
	return cache.RecordBuild("webapp-static", sources, []string{"generate-js"}, []string{webStatic})
}

// buildOptimizedManager builds manager binary with caching
func buildOptimizedManager(cache *BuildCache) error {
	sources := []string{
		"cmd/flamenco-manager/**/*.go",
		"internal/manager/**/*.go",
		"pkg/**/*.go",
		"go.mod",
		"go.sum",
	}
	outputs := []string{
		"flamenco-manager",
		"flamenco-manager.exe",
	}
	
	needsBuild, err := cache.NeedsBuild("manager", sources, []string{"generate-go", "webapp-static"}, outputs)
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: Manager binary is up to date")
		return cache.RestoreFromCache("manager", outputs)
	}
	
	fmt.Println("Cache: Building manager binary")
	if err := build("./cmd/flamenco-manager"); err != nil {
		return err
	}
	
	// Record successful build and cache binary
	if err := cache.RecordBuild("manager", sources, []string{"generate-go", "webapp-static"}, outputs); err != nil {
		return err
	}
	return cache.CopyToCache("manager", outputs)
}

// buildOptimizedWorker builds worker binary with caching
func buildOptimizedWorker(cache *BuildCache) error {
	sources := []string{
		"cmd/flamenco-worker/**/*.go",
		"internal/worker/**/*.go",
		"pkg/**/*.go",
		"go.mod",
		"go.sum",
	}
	outputs := []string{
		"flamenco-worker",
		"flamenco-worker.exe",
	}
	
	needsBuild, err := cache.NeedsBuild("worker", sources, []string{"generate-go"}, outputs)
	if err != nil {
		return err
	}
	
	if !needsBuild {
		fmt.Println("Cache: Worker binary is up to date")
		return cache.RestoreFromCache("worker", outputs)
	}
	
	fmt.Println("Cache: Building worker binary")
	if err := build("./cmd/flamenco-worker"); err != nil {
		return err
	}
	
	// Record successful build and cache binary
	if err := cache.RecordBuild("worker", sources, []string{"generate-go"}, outputs); err != nil {
		return err
	}
	return cache.CopyToCache("worker", outputs)
}

// Incremental build functions

// buildIncrementalGenerate handles incremental code generation
func buildIncrementalGenerate(cache *BuildCache) error {
	fmt.Println("Build: Checking code generation")
	
	// Check each generation step independently
	tasks := []struct {
		name string
		fn   func() error
	}{
		{"Go generation", func() error { return buildOptimizedGenerateGo(cache) }},
		{"Python generation", func() error { return buildOptimizedGeneratePy(cache) }},
		{"JavaScript generation", func() error { return buildOptimizedGenerateJS(cache) }},
	}
	
	for _, task := range tasks {
		if err := task.fn(); err != nil {
			return fmt.Errorf("%s failed: %w", task.name, err)
		}
	}
	
	return nil
}

// buildIncrementalWebapp handles incremental webapp building
func buildIncrementalWebapp(cache *BuildCache) error {
	fmt.Println("Build: Checking webapp")
	return buildOptimizedWebappStatic(cache)
}

// buildIncrementalBinaries handles incremental binary building
func buildIncrementalBinaries(cache *BuildCache) error {
	fmt.Println("Build: Checking binaries")
	
	// Check manager
	if err := buildOptimizedManager(cache); err != nil {
		return fmt.Errorf("manager build failed: %w", err)
	}
	
	// Check worker
	if err := buildOptimizedWorker(cache); err != nil {
		return fmt.Errorf("worker build failed: %w", err)
	}
	
	return nil
}

// Cache management functions

// CleanCache removes all build cache data
func CleanCache() error {
	cache := NewBuildCache()
	return cache.CleanCache()
}

// CacheStatus shows build cache statistics
func CacheStatus() error {
	cache := NewBuildCache()
	stats, err := cache.CacheStats()
	if err != nil {
		return err
	}
	
	fmt.Println("Build Cache Status:")
	fmt.Printf("  Targets cached: %d\n", stats["targets_cached"])
	fmt.Printf("  Cache size: %d MB (%d bytes)\n", stats["cache_size_mb"], stats["cache_size_bytes"])
	
	return nil
}