gopatterns/cmd/gopatterns/gopatterns.go

package main

import (
	_ "embed"
	"flag"
	"fmt"
	"log/slog"
	"os"
	gotemplate "text/template"

	"git.wtrh.nl/patterns/gopatterns/pkg/pattern/template"
	"gitlab.com/slxh/go/env"
)

//go:embed combined_pdf.tex.template
var texTemplate string

func main() {
	var (
		templateDir string
		outputDir   string
		help        bool
		debug       bool
	)

	flag.StringVar(&templateDir, "templates", "templates", "Directory with template files")
	flag.StringVar(&outputDir, "out", ".", "output directory")
	flag.BoolVar(&help, "help", false, "show help")
	flag.BoolVar(&debug, "debug", false, "enable debug mode")

	if err := env.ParseWithFlags(); err != nil {
		slog.Error("parsing flags failed", "err", err)
		return
	}

	if help {
		fmt.Printf(`
Render patterns. Usage
gopatterns [-templates <template-dir>] [-out <output-dir>] input-file
`)
	}

	args := flag.Args()
	if len(args) == 0 {
		slog.Error("at least one pattern is required")
	}

	os.MkdirAll(outputDir, 0o770)

	storage, err := template.NewStorage(templateDir)
	if err != nil {
		slog.Error("failed to open template directory", "err", err, "dir", templateDir)
		return
	}

	files := make([]string, 0)

	for _, arg := range args {
		pattern, err := template.LoadPattern(arg)
		if err != nil {
			slog.Error("failed to load pattern", "err", err)
			return
		}

		filenames, err := storage.RenderPatterns(pattern, outputDir, debug)
		if err != nil {
			slog.Error("error occurred while creating pattern", "pattern", arg, "err", err)
			return
		}

		files = append(files, filenames...)
	}

	generateLatex(outputDir, files...)
}

func generateLatex(outDir string, filenames ...string) {
	open, err := os.OpenFile(outDir+"/combined_pdf.tex", os.O_RDWR+os.O_CREATE+os.O_TRUNC, 0o640)
	if err != nil {
		panic(err)
	}

	defer open.Close()

	parse, err := gotemplate.New("latex").Parse(texTemplate)
	if err != nil {
		panic(err)
	}

	err = parse.Execute(open, filenames)
	if err != nil {
		panic(err)
	}
}