package host

import (
	"bufio"
	"bytes"
	"errors"
	"path/filepath"
	"regexp"
	"strings"
)

var errActivation = errors.New("claim activation: input or protected state refused")

func activationEnvironment(raw []byte) (map[string]string, error) {
	values := map[string]string{}
	scan := bufio.NewScanner(bytes.NewReader(raw))
	for scan.Scan() {
		line := strings.TrimSpace(scan.Text())
		if line == "" || strings.HasPrefix(line, "#") || strings.HasPrefix(line, ";") {
			continue
		}
		key, value, ok := strings.Cut(line, "=")
		key = strings.TrimSpace(key)
		value = strings.TrimSpace(value)
		if !ok || !regexp.MustCompile(`^[A-Za-z_][A-Za-z0-9_]*$`).MatchString(key) {
			return nil, errActivation
		}
		if _, exists := values[key]; exists {
			return nil, errActivation
		}
		if len(value) >= 2 && (value[0] == '"' && value[len(value)-1] == '"' || value[0] == '\'' && value[len(value)-1] == '\'') {
			value = value[1 : len(value)-1]
		}
		if strings.ContainsAny(value, "\\\"'\x00\r\n") {
			return nil, errActivation
		}
		values[key] = value
	}
	if scan.Err() != nil {
		return nil, scan.Err()
	}
	return values, nil
}

func activationUnitSettings(raw []byte) (claimUnitSettings, error) {
	v, err := activationEnvironment(raw)
	if err != nil {
		return claimUnitSettings{}, err
	}
	cfg := claimUnitSettings{enabled: strings.TrimSpace(v["CARLOS_HOST_CLAIM"]) != "", data: v["CARLOS_DATA_DIR"], opt: v["CARLOS_OPT_DIR"]}
	if !cfg.enabled || v["CARLOS_REGION"] != "" {
		return claimUnitSettings{}, errActivation
	}
	if cfg.data == "" {
		cfg.data = "/data"
	}
	if cfg.opt == "" {
		cfg.opt = "/opt/carlos"
	}
	for _, p := range []string{cfg.data, cfg.opt} {
		if !filepath.IsAbs(p) || filepath.Clean(p) != p || p == "/" || strings.ContainsAny(p, "\x00\r\n") {
			return claimUnitSettings{}, errActivation
		}
	}
	return cfg, nil
}

type activationFenceScope struct{ Bucket, Region, Role string }