package main

import (
  "log"
  "fmt"
  "strings"
  "io/fs"
  "path/filepath"
  "os"
  "github.com/gofiber/fiber/v2"
  "github.com/gofiber/template/html/v2"
  "zedshaw.games/ssgod/config"
)

func Fail(err error, format string, v ...any) error {
  err_format := fmt.Sprintf("ERROR: %v; %s", err, format)
  log.Printf(err_format, v...)
  return err
}


func ProcessDirEntry(engine *html.Engine, path string, d fs.DirEntry, err error) error  {
  settings := config.Settings

  if !d.IsDir() {
    if err != nil { return Fail(err, "path: %s", path); }

    dir := filepath.Dir(path)
    err = os.MkdirAll(dir, 0750)
    if err != nil {
      return Fail(err, "making dir %s", dir);
    }

    split_path := strings.Split(path, string(os.PathSeparator))[1:]
    source_name := strings.Join(split_path, "/")  // Render wants / even on windows
    ext := filepath.Ext(source_name)
    template_name, found := strings.CutSuffix(source_name, ext)

    if found && ext == ".html" && template_name != settings.Layout {
      prefixed_path := append([]string{settings.Target}, split_path...)

      target_path := filepath.Join(prefixed_path...)
      _, err := os.Stat(target_path)

      if os.IsNotExist(err) {
        target_dir := filepath.Dir(target_path)
        log.Println("MAKING: ", target_dir)
        os.MkdirAll(target_dir, 0750)
      }

      // TODO: compare time stamps and skip if not newer

      out, err := os.OpenFile(target_path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
      if err != nil { return Fail(err, "writing file %s", target_path) }

      // generate a data-testid for all pages based on template name
      page_id := strings.ReplaceAll(template_name, "/", "-") + "-page"

      err = engine.Render(out, template_name, fiber.Map{"PageId": page_id}, settings.Layout)
      if err != nil { return Fail(err, "failed to render %s", path) }

      log.Printf("RENDER: %s -> %s", template_name, target_path)
      out.Close()
    }
  }

  return nil
}

func RenderPages() {
  engine := html.New(config.Settings.Views, ".html")
  engine.Load()

  err := filepath.WalkDir(config.Settings.Views,
    func (path string, d fs.DirEntry, err error) error  {
        return ProcessDirEntry(engine, path, d, err)
  })

  if err != nil { log.Fatalf("can't walk content") }
}

func main() {
  config.Load("ssgod.toml")
  log.Printf("views=%s, layouts=%s, target=%s",
    config.Settings.Views, config.Settings.Layout, config.Settings.Target)

  RenderPages()
}