// Package app 应用容器：装配配置、数据库、密码/加密/JWT 与记账器。
package app

import (
	"context"
	"log"
	"time"

	"github.com/openteam/server/internal/config"
	"github.com/openteam/server/internal/pkg/crypto"
	"github.com/openteam/server/internal/pkg/jwt"
	"github.com/openteam/server/internal/store"
	"github.com/openteam/server/internal/usage"
	"gorm.io/gorm"
)

type App struct {
	Cfg       *config.Config
	DB        *gorm.DB
	Hasher    *crypto.PasswordHasher
	Enc       *crypto.Encryptor
	JWT       *jwt.Manager
	Usage     *usage.Recorder
	startedAt time.Time
}

func New(cfg *config.Config) (*App, error) {
	db, err := store.Open(cfg.DB.Driver, cfg.DB.DSN)
	if err != nil {
		return nil, err
	}

	a := &App{
		Cfg:       cfg,
		DB:        db,
		Hasher:    crypto.NewPasswordHasher(cfg.Auth.Argon2Time, cfg.Auth.Argon2Memory, cfg.Auth.Argon2Threads, cfg.Auth.Argon2KeyLen, cfg.Auth.SaltLen),
		Enc:       crypto.NewEncryptor(cfg.Master),
		JWT:       jwt.NewManager(cfg.JWT.Secret, cfg.JWT.Issuer, cfg.JWT.AccessTTL, cfg.JWT.RefreshTTL),
		startedAt: time.Now(),
	}
	a.Usage = usage.NewRecorder(db)

	if err := a.Seed(); err != nil {
		return nil, err
	}
	return a, nil
}

func (a *App) Close() {
	a.Usage.Close()
}

// Seed 首次启动初始化：管理员账号 + 默认渠道 + 默认模型。
func (a *App) Seed() error {
	// 1. 管理员（从环境变量读取，默认 admin/admin123，生产必须改）
	var count int64
	a.DB.Model(&store.User{}).Where("role = ?", store.RoleAdmin).Count(&count)
	if count == 0 {
		hash, err := a.Hasher.HashPassword(envOr("OT_ADMIN_PASSWORD", "admin123"))
		if err != nil {
			return err
		}
		admin := store.User{
			Username:     envOr("OT_ADMIN_USERNAME", "admin"),
			Email:        envOr("OT_ADMIN_EMAIL", "admin@localhost"),
			PasswordHash: hash,
			Role:         store.RoleAdmin,
			Balance:      1000, // 初始余额，便于联调；生产由充值/调整决定
			Status:       store.UserStatusActive,
		}
		if err := a.DB.Create(&admin).Error; err != nil {
			return err
		}
		log.Printf("seed: created admin user %q (change the default password!)", admin.Username)
	}

	// 2. 默认渠道（配置了上游 key 时创建）
	if a.Cfg.Proxy.UpstreamKey != "" {
		var chCount int64
		a.DB.Model(&store.Channel{}).Count(&chCount)
		if chCount == 0 {
			enc, err := a.Enc.Encrypt(a.Cfg.Proxy.UpstreamKey)
			if err != nil {
				return err
			}
			ch := store.Channel{
				Name:          a.Cfg.Proxy.DefaultChannelName,
				Provider:      store.ChannelProviderOpenAI,
				BaseURL:       a.Cfg.Proxy.UpstreamBaseURL,
				APIKeyEnc:     enc,
				Weight:        1,
				Priority:      0,
				TimeoutMS:     int(a.Cfg.Proxy.Timeout / time.Millisecond),
				MaxConcurrency: 16,
				HealthStatus:  store.ChannelHealthHealthy,
				Enabled:       true,
			}
			if err := a.DB.Create(&ch).Error; err != nil {
				return err
			}
			// 默认模型 + 绑定
			m := store.Model{
				Name:        a.Cfg.Proxy.DefaultModel,
				DisplayName: a.Cfg.Proxy.DefaultModel,
				InputPrice:  0.15,  // 每百万 token，示例价
				OutputPrice: 0.60,
				Enabled:     true,
			}
			if err := a.DB.Create(&m).Error; err == nil {
				a.DB.Create(&store.ChannelModelBinding{ChannelID: ch.ID, ModelID: m.ID, UpstreamModel: m.Name})
			}
			log.Printf("seed: created default channel %q (%s)", ch.Name, ch.BaseURL)
		}
	}
	return nil
}

func (a *App) Shutdown(ctx context.Context) {
	a.Usage.Close()
	if sqlDB, err := a.DB.DB(); err == nil {
		_ = sqlDB.Close()
	}
	_ = ctx
}

func envOr(key, fallback string) string {
	v := envLookup(key)
	if v == "" {
		return fallback
	}
	return v
}