package config

import (
	"os"
	"path/filepath"
	"strings"
	"time"

	"git.misaka.ren/M1saka/zhanlu_proxy/internal/auth"
)

type Config struct {
	ListenAddr         string
	MobileLoginBaseURL string
	MobileModelBaseURL string
	UpstreamPath       string
	CredentialsPath    string
	SSOExchangeURL     string
	SSOBaseURL         string
	TokenDecryptKey    string
	PublicKeyPEM       string
	PhonePublicKeyPEM  string
	SM2PrivateKey      string
	OpenAIAPIKey       string
	LoginPassword      string
	PluginVersion      string
	UpstreamTimeout    time.Duration
	StreamIdleTimout   time.Duration
	Debug              bool
	Credentials        auth.Credentials
}

func Load() (Config, error) {
	cfg := Config{
		ListenAddr:         getenv("ZHANLU_LISTEN_ADDR", ":8080"),
		MobileLoginBaseURL: firstNonEmpty(os.Getenv("ZHANLU_MOBILE_LOGIN_BASE_URL"), getenv("ZHANLU_SERVER_BASE_URL", "https://ecloud.10086.cn")),
		MobileModelBaseURL: getenv("ZHANLU_MOBILE_MODEL_BASE_URL", "https://ecloud.10086.cn/api/query/aigateway"),
		UpstreamPath:       getenv("ZHANLU_UPSTREAM_PATH", "/chat/completions"),
		CredentialsPath:    getenv("ZHANLU_CREDENTIALS_FILE", defaultCredentialsPath()),
		SSOBaseURL:         getenv("ZHANLU_SSO_BASE_URL", "http://4c.hq.cmcc"),
		SSOExchangeURL:     getenv("ZHANLU_SSO_EXCHANGE_URL", "http://rdcloud.4c.hq.cmcc/cmdevops-aiplus-agent-gateway/api/acepilot/zhanlu/authToken"),
		TokenDecryptKey:    getenv("ZHANLU_TOKEN_DECRYPT_KEY", "3jw7woww2rvhla6k"),
		PublicKeyPEM:       getenv("ZHANLU_PUBLIC_KEY_PEM", defaultPublicKeyPEM),
		PhonePublicKeyPEM:  getenv("ZHANLU_PHONE_PUBLIC_KEY_PEM", defaultPhonePublicKeyPEM),
		SM2PrivateKey:      getenv("ZHANLU_APIKEY_AUTH_SM2_PRIVATE_KEY", defaultSM2PrivateKey),
		OpenAIAPIKey:       os.Getenv("OPENAI_COMPAT_API_KEY"),
		LoginPassword:      os.Getenv("ZHANLU_LOGIN_PASSWORD"),
		PluginVersion:      getenv("ZHANLU_PLUGIN_VERSION", "1.4.2"),
		UpstreamTimeout:    durationEnv("ZHANLU_UPSTREAM_TIMEOUT", 300*time.Second),
		StreamIdleTimout:   durationEnv("ZHANLU_STREAM_IDLE_TIMEOUT", 300*time.Second),
		Debug:              strings.EqualFold(os.Getenv("ZHANLU_DEBUG"), "true"),
	}
	cfg.Credentials = auth.Credentials{
		AccessKey: os.Getenv("ZHANLU_ACCESS_KEY"),
		SecretKey: os.Getenv("ZHANLU_SECRET_KEY"),
		Token:     os.Getenv("ZHANLU_TOKEN"),
		APIKey:    os.Getenv("ZHANLU_API_KEY"),
	}
	if cfg.Credentials.Validate() == nil || cfg.Credentials.HasAPIKey() {
		return cfg, nil
	}
	if creds, err := auth.LoadCredentials(cfg.CredentialsPath); err == nil {
		cfg.Credentials = creds
	}
	return cfg, nil
}

func getenv(key, fallback string) string {
	if v := strings.TrimSpace(os.Getenv(key)); v != "" {
		return v
	}
	return fallback
}

func durationEnv(key string, fallback time.Duration) time.Duration {
	v := strings.TrimSpace(os.Getenv(key))
	if v == "" {
		return fallback
	}
	d, err := time.ParseDuration(v)
	if err != nil {
		return fallback
	}
	return d
}

func firstNonEmpty(values ...string) string {
	for _, v := range values {
		if strings.TrimSpace(v) != "" {
			return v
		}
	}
	return ""
}

func defaultCredentialsPath() string {
	return filepath.Join(".", "credentials.json")
}

const defaultPublicKeyPEM = `-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAhxudxTewPgljUHEZHkusP7m3I+zA4/RGvuUMt6TtII/m4zwUOm/Y31zHBTmkCCt8k5vj9y+AmO0TsGmHooNQuMebakdmEWdcA5h7YAHHFbF2w5LcxIXjib08vgVpA+m3R5xPbLK+vfHe2aAX36b5nHReDNncY5vAl3U4CgIEBGPqyG67vJytRWqP+sfEdw5+m192Rf4SCGyiBzRmjiVlH3zeEBjdbOrkAnzKOVz6AHBl2q7LPLJKIzxjoAyhEp5qnDjHUFo5VZUgFwUOt83A/jbGMyzmjRoxBuvKcs9tBuorZyUwIsZN6E+rtQk2YqMPj4RkDsZ7LRmj6on8sN2rHQIDAQAB
-----END PUBLIC KEY-----`

const defaultPhonePublicKeyPEM = `-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAnqiA2qP9BNvKw5DnVnrBVBhd+5gJDVn3mDemCfq/AN1cdaHV57hQo6R1ufp45mOkSwLaJcTE82zFKmgKoEAKwD1SR10rp0xJC7x3yvx2FbpEsiW9TeZlvJdri1BYKUMS8OP8ykjHSJoy0oMaV6e95R2rsu4DEH7JuA9+Bt0sOoLewvHx/fs1e28tH+928uUEKdLug+cv/XTKjLudpLjiSMPZU6EHFqrUhA9zmEasOMmg9Dj0j4sChBooCeCGnh/pYHJaosH5amhlSQ8FnEG0BQBrQbZ+qhRH4LYyqGYN8grDNeSnPj7vPDcwiEm++85i5AngZfEMnGWZg5jYDhO9+QIDAQAB
-----END PUBLIC KEY-----`

const defaultSM2PrivateKey = "8d6ee90b3c4d299ae5abd655dbc3547c110ae8aeff1de18b0df241f215f90748"