package models

import (
	"encoding/json"
	"errors"
	"fmt"
	"io/fs"
	"os"
	"path/filepath"

	"github.com/rs/zerolog/log"
)

const (
	MainDir string = ".homeserver"

	ComposeFile string = "docker-compose.deploy.yml"
	EnvFile            = ".env"
	NginxFile          = "nginx.conf"

	ConfFile = "hmdeploy.json"
)

var (
	ErrInvalidEnvFile     = errors.New("unable to stat .env file")
	ErrInvalidComposeFile = errors.New("unable to stat compose file")
	ErrInvalidNginxFile   = errors.New("unable to stat nginx file")
)

func getFileInfo(baseDir, filePath string) (fs.FileInfo, error) {
	var fInf fs.FileInfo

	filePath = filepath.Clean(filePath)
	filePath = filepath.Join(baseDir, filePath)

	composePath, err := filepath.Abs(filePath)
	if err != nil {
		return fInf, fmt.Errorf("%w, %v", ErrInvalidComposeFile, err)
	}

	fInf, err = os.Stat(composePath)
	if err != nil {
		return fInf, fmt.Errorf("%w, %v", ErrInvalidComposeFile, err)
	}

	return fInf, nil
}

type Project struct {
	Name      string `json:"name"`
	Dir       string
	ImageName string `json:"image"`
	Deps      struct {
		EnvFile     string `json:"env"`
		EnvFileInfo fs.FileInfo

		ComposeFile     string `json:"compose"`
		ComposeFileInfo fs.FileInfo

		NginxFile     string `json:"nginx"`
		NginxFileInfo fs.FileInfo
	} `json:"dependencies"`
}

func (p *Project) validate() error {
	cfs, err := getFileInfo(p.Dir, p.Deps.ComposeFile)
	if err != nil {
		return fmt.Errorf("%w, %v", ErrInvalidComposeFile, err)
	}
	p.Deps.ComposeFileInfo = cfs

	if p.Deps.EnvFile != "" {
		efs, err := getFileInfo(p.Dir, p.Deps.EnvFile)
		if err != nil {
			return fmt.Errorf("%w, %v", ErrInvalidEnvFile, err)
		}
		p.Deps.EnvFileInfo = efs
	} else {
		log.Warn().Msg("no .env file provided, hoping one is set elsewhere...")
	}

	nfs, err := getFileInfo(p.Dir, p.Deps.EnvFile)
	if err != nil {
		return fmt.Errorf("%w, %v", ErrInvalidNginxFile, err)
	}
	p.Deps.NginxFileInfo = nfs

	return nil
}

func ProjectFromDir(dir string) (Project, error) {
	var p Project

	dir = filepath.Join(dir, MainDir)
	p.Dir = dir

	content, err := os.ReadFile(filepath.Join(dir, ConfFile))
	if err != nil {
		log.Err(err).Str("dir", dir).Str("conf", ConfFile).Msg("unable to read conf file")
		return p, err
	}

	if err := json.Unmarshal(content, &p); err != nil {
		log.Err(err).Str("dir", dir).Str("conf", ConfFile).Msg("unable to parse conf file")
		return p, err
	}

	if err := p.validate(); err != nil {
		log.Err(err).Str("dir", dir).Msg("unable to validate project")
		return p, err
	}

	return p, nil
}