package config

import (
    "bufio"
    "os"
    "strings"
)

type Config struct {
    Port               string
    JWTSecret          string
    AdminUsername      string
    AdminPassword      string
    OSSEndpoint        string
    OSSAccessKeyID     string
    OSSAccessKeySecret string
    OSSBucket          string
    DBDsn              string
    AllowRegistration  bool
    LoginRequireCaptcha bool
    RegisterRequireCaptcha bool
}

func getenv(key, def string) string {
    v := os.Getenv(key)
    if v == "" {
        return def
    }
    return v
}

func Load() Config {
    // Auto-load .env if present to reduce startup parameters.
    loadDotEnv()
    return Config{
        Port:               getenv("PORT", "8080"),
        JWTSecret:          getenv("JWT_SECRET", "change-me"),
        AdminUsername:      os.Getenv("ADMIN_USERNAME"),
        AdminPassword:      os.Getenv("ADMIN_PASSWORD"),
        OSSEndpoint:        os.Getenv("OSS_ENDPOINT"),
        OSSAccessKeyID:     os.Getenv("OSS_ACCESS_KEY_ID"),
        OSSAccessKeySecret: os.Getenv("OSS_ACCESS_KEY_SECRET"),
        OSSBucket:          os.Getenv("OSS_BUCKET"),
        DBDsn:              os.Getenv("DB_DSN"),
        AllowRegistration:  parseBool(getenv("ALLOW_REGISTRATION", "true")),
        LoginRequireCaptcha: parseBool(getenv("LOGIN_REQUIRE_CAPTCHA", "true")),
        RegisterRequireCaptcha: parseBool(getenv("REGISTER_REQUIRE_CAPTCHA", "true")),
    }
}

// loadDotEnv loads environment variables from a local .env file if present.
// It only sets variables that are not already defined in the process env.
func loadDotEnv() {
    f, err := os.Open(".env")
    if err != nil {
        return
    }
    defer f.Close()
    s := bufio.NewScanner(f)
    for s.Scan() {
        line := strings.TrimSpace(s.Text())
        if line == "" || strings.HasPrefix(line, "#") {
            continue
        }
        if i := strings.Index(line, "="); i != -1 {
            key := strings.TrimSpace(line[:i])
            val := strings.TrimSpace(line[i+1:])
            if len(val) >= 2 {
                if (val[0] == '"' && val[len(val)-1] == '"') || (val[0] == '\'' && val[len(val)-1] == '\'') {
                    val = val[1 : len(val)-1]
                }
            }
            if os.Getenv(key) == "" {
                _ = os.Setenv(key, val)
            }
        }
    }
}

func parseBool(v string) bool {
    switch strings.ToLower(strings.TrimSpace(v)) {
    case "1", "true", "yes", "on":
        return true
    default:
        return false
    }
}