package service

import (
	"archive/zip"
	"bytes"
	"encoding/json"
	"fmt"
	"time"

	"gpt-plus/internal/db"

	"gorm.io/gorm"
)

type authFile struct {
	OpenAIAPIKey string     `json:"OPENAI_API_KEY"`
	AccessToken  string     `json:"access_token"`
	IDToken      string     `json:"id_token"`
	LastRefresh  string     `json:"last_refresh"`
	RefreshToken string     `json:"refresh_token"`
	Tokens       authTokens `json:"tokens"`
}

type authTokens struct {
	AccessToken  string `json:"access_token"`
	AccountID    string `json:"account_id"`
	IDToken      string `json:"id_token"`
	LastRefresh  string `json:"last_refresh"`
	RefreshToken string `json:"refresh_token"`
}

func buildAuthFile(acct *db.Account) *authFile {
	now := time.Now().UTC().Format("2006-01-02T15:04:05Z")
	token := acct.AccessToken
	if acct.WorkspaceToken != "" {
		token = acct.WorkspaceToken
	}
	accountID := acct.AccountID
	if acct.TeamWorkspaceID != "" {
		accountID = acct.TeamWorkspaceID
	}
	return &authFile{
		AccessToken:  token,
		IDToken:      acct.IDToken,
		LastRefresh:  now,
		RefreshToken: acct.RefreshToken,
		Tokens: authTokens{
			AccessToken:  token,
			AccountID:    accountID,
			IDToken:      acct.IDToken,
			LastRefresh:  now,
			RefreshToken: acct.RefreshToken,
		},
	}
}

// ExportAccounts exports accounts as auth.json files.
// If multiple files, returns a zip archive.
func ExportAccounts(d *gorm.DB, ids []uint, note string) ([]byte, string, error) {
	var accounts []db.Account
	d.Where("id IN ?", ids).Find(&accounts)

	if len(accounts) == 0 {
		return nil, "", fmt.Errorf("未找到账号")
	}

	// Collect all files to export
	type exportFile struct {
		Name string
		Data []byte
	}
	var files []exportFile

	for _, acct := range accounts {
		auth := buildAuthFile(&acct)
		data, _ := json.MarshalIndent(auth, "", "    ")
		files = append(files, exportFile{
			Name: acct.Email + ".auth.json",
			Data: data,
		})

		// If team_owner, also export sub-accounts
		if acct.Plan == "team_owner" {
			var subs []db.Account
			d.Where("parent_id = ?", acct.ID).Find(&subs)
			for _, sub := range subs {
				subAuth := buildAuthFile(&sub)
				subData, _ := json.MarshalIndent(subAuth, "", "    ")
				files = append(files, exportFile{
					Name: sub.Email + ".auth.json",
					Data: subData,
				})
			}
		}
	}

	// Single file — return directly
	if len(files) == 1 {
		return files[0].Data, files[0].Name, nil
	}

	// Multiple files — zip archive
	var buf bytes.Buffer
	zw := zip.NewWriter(&buf)
	for _, f := range files {
		w, err := zw.Create(f.Name)
		if err != nil {
			return nil, "", err
		}
		w.Write(f.Data)
	}
	zw.Close()

	ts := time.Now().Format("20060102_150405")
	filename := fmt.Sprintf("export_%s_%s.zip", note, ts)
	if note == "" {
		filename = fmt.Sprintf("export_%s.zip", ts)
	}

	return buf.Bytes(), filename, nil
}