package config

import (
	"os"
	"path/filepath"
	"strconv"
)

// Config 全局配置，从环境变量读取（带默认值）。
// system_config 表中的值在运行时覆盖对应字段（见 service）。
type Config struct {
	Port         string
	DBPath       string // SQLite 文件路径
	JWTSecret    string
	JWTExpireMin int

	LLMBaseURL string
	LLMAPIKey  string
	LLMModel   string
	EmbedModel string

	KnowledgeServiceURL string
	KnowledgeIndexDir   string

	KBDataDir          string
	KnowledgeSourceDir string

	FileMaxDoc     int64
	FileMaxVideo   int64
	ChunkThreshold int64

	LibreOfficeBin string
	PdftotextBin   string

	KingdeeBaseURL    string
	KingdeeAccountID  string
	KingdeeUsername   string
	KingdeePassword   string
	KingdeeLCID       int
	KingdeeTimeoutSec int
}

// Load 读取环境变量构造配置。缺失的用默认值（部署时通过 .env / systemd 注入）。
func Load() *Config {
	baseDir := backendBaseDir()

	return &Config{
		Port:         getenv("PORT", "8080"),
		DBPath:       getenv("DB_PATH", filepath.Join(baseDir, "data", "eai_agentplatform.db")),
		JWTSecret:    getenv("JWT_SECRET", "change-this-to-a-strong-secret-in-production"),
		JWTExpireMin: getenvInt("JWT_EXPIRE_MINUTES", 480),

		LLMBaseURL: getenv("LLM_BASE_URL", "http://127.0.0.1:11434/v1"),
		LLMAPIKey:  getenv("LLM_API_KEY", "ollama"),
		LLMModel:   getenv("LLM_MODEL", "qwen2.5:7b"),
		EmbedModel: getenv("EMBED_MODEL", "bge-m3"),

		KnowledgeServiceURL: getenv("KNOWLEDGE_SERVICE_URL", "http://127.0.0.1:10233"),
		KnowledgeIndexDir:   getenv("KNOWLEDGE_INDEX_DIR", filepath.Join(baseDir, "data", "faiss")),

		KBDataDir:          getenv("KB_DATA_DIR", filepath.Join(baseDir, "data", "kb_data")),
		KnowledgeSourceDir: getenv("KNOWLEDGE_SOURCE_DIR", filepath.Join(baseDir, "knowledge_source")),

		FileMaxDoc:     getenvInt64("FILE_MAX_SIZE_DOC", 209715200),
		FileMaxVideo:   getenvInt64("FILE_MAX_SIZE_VIDEO", 2147483648),
		ChunkThreshold: getenvInt64("CHUNK_THRESHOLD", 104857600),

		LibreOfficeBin: getenv("LIBREOFFICE_BIN", "libreoffice"),
		PdftotextBin:   getenv("PDFTOTEXT_BIN", "pdftotext"),

		KingdeeBaseURL:    getenv("KINGDEE_BASE_URL", ""),
		KingdeeAccountID:  getenv("KINGDEE_ACCOUNT_ID", ""),
		KingdeeUsername:   getenv("KINGDEE_USERNAME", ""),
		KingdeePassword:   getenv("KINGDEE_PASSWORD", ""),
		KingdeeLCID:       getenvInt("KINGDEE_LCID", 2052),
		KingdeeTimeoutSec: getenvInt("KINGDEE_TIMEOUT_SEC", 15),
	}
}

func backendBaseDir() string {
	if exe, err := os.Executable(); err == nil && exe != "" {
		return filepath.Clean(filepath.Join(filepath.Dir(exe), ".."))
	}
	if wd, err := os.Getwd(); err == nil && wd != "" {
		return wd
	}
	return "."
}

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

func getenvInt(key string, def int) int {
	if v := os.Getenv(key); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			return n
		}
	}
	return def
}

func getenvInt64(key string, def int64) int64 {
	if v := os.Getenv(key); v != "" {
		if n, err := strconv.ParseInt(v, 10, 64); err == nil {
			return n
		}
	}
	return def
}