package fhelp

import (
	"os"
	"path/filepath"

	"go.wit.com/log"
)

// This defines the "default" behavior for forge when doing GO lang development
//
// Since this code is common, it's in a seperate package so it can be used elsewhere
//
// The default behavior is:
//
//   * If your current directory or parent directory has a go.work file, make that your default spot
//   * Otherwise, set the default to ~/go/src
//
// This routine ensures the following ENV vars are set:
//
// FORGE_CONFIG == where forge's configs are stored (normally ~/.config/forge)
// FORGE_REPOPB == where the repos.pb protobuf cache file is stored (normally ~/.cache/forge/repos.pb)
// FORGE_GOSRC  == based on the path, what the user probably want for developing in GO (Defaults to ~/go/src)
// FORGE_GOWORK == true or false depending on the GOSRC result
//
// returns:
// string	# ~/go/src or the path to the go.work file
// bool	# true if the user is using a go.work file
// err	# if everything goes wrong, the error
//

func ConfigureVerboseENV() error {
	err := ConfigureENV()
		log.Printf("FORGE_CONFIG   = %s\n", os.Getenv("FORGE_CONFIG"))
		log.Printf("FORGE_GOSRC    = %s\n", os.Getenv("FORGE_GOSRC"))
		log.Printf("FORGE_GOWORK   = %v\n", os.Getenv("FORGE_GOWORK"))
		log.Printf("FORGE_REPOPB   = %s\n", os.Getenv("FORGE_REPOPB"))
		log.Printf("FORGE_URL      = %s\n", os.Getenv("FORGE_URL"))
		log.Printf("FORGE_PATCHDIR = %s\n", os.Getenv("FORGE_PATCHDIR"))
		log.Printf("HOSTNAME       = %s\n", os.Getenv("HOSTNAME"))
		return err
}

// set the ENV vars
// always set them to _something_ even when everything seems to be failing
func ConfigureENV() error {
	var anyerr error
	// setup the forge config dir
	if os.Getenv("FORGE_CONFIG") == "" {
		homeDir, err := os.UserHomeDir()
		if err == nil {
			fullpath := filepath.Join(homeDir, ".config/forge")
			os.MkdirAll(fullpath, os.ModePerm)
			os.Setenv("FORGE_CONFIG", fullpath)
		} else {
			log.Info("user home dir error", err)
			os.Setenv("FORGE_CONFIG", "/tmp")
			anyerr = err
		}
	}

	// setting FORGE_URL
	if os.Getenv("FORGE_URL") == "" {
		os.Setenv("FORGE_URL", "https://forge.wit.com/")
	}

	// hostname is needed. allow ENV to pass it in
	if os.Getenv("HOSTNAME") == "" {
		if hname, err := os.Hostname(); err == nil {
			os.Setenv("HOSTNAME", hname)
		} else {
			os.Setenv("HOSTNAME", "unconfigured.hostname.forge")
		}
	}

	// if this env is already set, just use what is there
	if os.Getenv("FORGE_GOSRC") != "" {
		// always use this ENV if it is set
		os.Setenv("FORGE_REPOPB", os.Getenv("FORGE_GOSRC")) // store repos.pb in the same dir
		if goWorkExists(os.Getenv("FORGE_GOSRC")) {
			os.Setenv("FORGE_GOWORK", "true")
		}
		if os.Getenv("FORGE_PATCHDIR") == "" {
			os.Setenv("FORGE_PATCHDIR", os.Getenv("FORGE_GOSRC"))
		}
		return anyerr
	}

	// if a go.work file is found, use that location
	if gowork, ok := findGoWork(); ok {
		os.Setenv("FORGE_GOSRC", gowork)
		if os.Getenv("FORGE_GOSRC") == "" {
			// everything went wrong. use /tmp maybe ?
			os.Setenv("FORGE_GOSRC", "/tmp")
		}
		os.Setenv("FORGE_REPOPB", os.Getenv("FORGE_GOSRC")) // store repos.pb in the same dir
		os.Setenv("FORGE_GOWORK", "true")
		if os.Getenv("FORGE_PATCHDIR") == "" {
			os.Setenv("FORGE_PATCHDIR", os.Getenv("FORGE_GOSRC"))
		}
		return anyerr
	} else {
		// log.Info("fhelp.findGoWork() didn't find a go.work file")
	}

	// there are no go.work files, use the default ~/go/src behavior
	if gosrc, err := useGoSrc(); err == nil {
		os.Setenv("FORGE_GOSRC", gosrc)
		os.Unsetenv("FORGE_GOWORK")
	}

	// set to user home dir unless this is already set
	if os.Getenv("FORGE_REPOPB") == "" {
		homeDir, err := os.UserHomeDir()
		if err == nil {
			fullpath := filepath.Join(homeDir, ".cache/forge")
			if err := os.MkdirAll(fullpath, os.ModePerm); err == nil {
				os.Setenv("FORGE_REPOPB", fullpath)
			} else {
				log.Warn("mkdir failed", fullpath, err)
				os.Setenv("FORGE_REPOPB", os.Getenv("FORGE_GOSRC")) // store repos.pb in the same dir
				anyerr = err
			}
		} else {
			log.Info("user home dir error", err)
			os.Setenv("FORGE_REPOPB", "/tmp")
			anyerr = err
		}
	}
	if os.Getenv("FORGE_PATCHDIR") == "" {
		os.Setenv("FORGE_PATCHDIR", os.Getenv("FORGE_REPOPB"))
	}

	return anyerr
}

// this is the 'old way" and works fine for me. I use it because I like the ~/go/src directory
// because I know exactly what is in it: GO stuff & nothing else
func useGoSrc() (string, error) {
	homeDir, err := os.UserHomeDir()
	if err != nil {
		return "", err
	}
	pwd := filepath.Join(homeDir, "go/src")
	err = os.MkdirAll(pwd, os.ModePerm)
	return pwd, err
}

func goWorkExists(dir string) bool {
	var err error
	workFilePath := filepath.Join(dir, "go.work")
	if _, err = os.Stat(workFilePath); err == nil {
		// log.Info("f.goWorkExists() found", workFilePath)
		return true
	} else if !os.IsNotExist(err) {
		// log.Info("f.goWorkExists() missing", workFilePath)
		return false
	}
	// probably false, but some other error
	// log.Info("f.goWorkExists() os.Stat() error", err, workFilePath)
	return false
}

// findGoWork searches for a "go.work" file starting from the current directory
// and moving up the directory tree. It returns the path to the directory containing
// the file and a boolean indicating whether the file was found.
func findGoWork() (string, bool) {
	dir, err := os.Getwd()
	if err != nil {
		return "", false
	}

	for {
		workFilePath := filepath.Join(dir, "go.work")
		if _, err := os.Stat(workFilePath); err == nil {
			return dir, true
		}
		parent := filepath.Dir(dir)
		if parent == dir {
			break // Reached root
		}
		dir = parent
	}

	return "", false
}