package replyexport

import (
	"strings"
)

// PolicyOptions 传递判定所需上下文
type PolicyOptions struct {
	Role               string
	Status             string // pending, streaming_status, auto_retrying, completed, failed, cancelled
	Content            string
	HasInteractiveCard bool
	HasError           bool
	IsCancelled        bool
	IsRestricted       bool // 内容合规策略是否禁止导出
	Revision           int
}

// EvaluatePolicy 权威判定一条消息的内容类型与导出能力
func EvaluatePolicy(opts PolicyOptions) (ContentKind, MessageExportCapability) {
	revision := opts.Revision
	if revision <= 0 {
		revision = 1
	}

	normContent := strings.TrimSpace(opts.Content)
	hash := ComputeSha256(normContent)

	cap := MessageExportCapability{
		Policy:          PolicyNone,
		Formats:         []string{},
		BodySelector:    "content_only",
		ContentRevision: revision,
		ContentSha256:   hash,
	}

	// 1. 非助手回复不可导出
	if opts.Role != "assistant" {
		cap.ReasonCode = ReasonNotAssistant
		return KindConversationalText, cap
	}

	// 2. 异常或已取消状态
	if opts.HasError || opts.IsCancelled || opts.Status == "failed" || opts.Status == "cancelled" {
		cap.ReasonCode = ReasonErrorOrCancelled
		return KindErrorNotice, cap
	}

	// 3. 流式中或未完成
	if opts.Status == "pending" || opts.Status == "streaming_status" || opts.Status == "auto_retrying" {
		cap.ReasonCode = ReasonNotCompleted
		return KindStatusUpdate, cap
	}

	// 4. 空正文
	if normContent == "" {
		if opts.HasInteractiveCard {
			cap.ReasonCode = ReasonCardOnly
			return KindActionCard, cap
		}
		cap.ReasonCode = ReasonEmptyBody
		return KindStatusUpdate, cap
	}

	// 5. 内容合规策略拦截
	if opts.IsRestricted {
		cap.ReasonCode = ReasonContentRestricted
		return KindDocumentText, cap
	}

	// 6. 纯交互卡片与短依赖引导语
	if opts.HasInteractiveCard {
		// 检查正文是否具备独立阅读价值
		isDependentPrompt := isDependentCardPrompt(normContent)
		if isDependentPrompt {
			cap.ReasonCode = ReasonCardOnly
			return KindActionCard, cap
		}

		// 正文具备独立性，允许导出，且明确仅导出 content
		cap.Policy = PolicyFull
		cap.Formats = FullFormats()
		return KindDocumentText, cap
	}

	// 7. 极短寒暄或瞬时确认答复：开放 copy_only，不保存为系统文档
	if isCasualOrVeryShort(normContent) {
		cap.Policy = PolicyCopyOnly
		cap.Formats = CopyOnlyFormats()
		return KindConversationalText, cap
	}

	// 8. 常规具备独立结构的助手正文
	cap.Policy = PolicyFull
	cap.Formats = FullFormats()
	return KindDocumentText, cap
}

// isDependentCardPrompt 判断正文是否仅仅是依赖卡片的简短引导语
func isDependentCardPrompt(content string) bool {
	runes := []rune(content)
	// 超过 80 字符且包含结构化 Markdown 标记的，通常为完整方案说明
	if len(runes) > 80 && (strings.Contains(content, "#") || strings.Contains(content, "- ") || strings.Contains(content, "|")) {
		return false
	}

	// 短于 50 字符且匹配经典卡片引导语模式
	if len(runes) <= 50 {
		lower := strings.ToLower(content)
		patterns := []string{
			"请确认", "请选择", "请核对", "点击下方", "操作如下",
			"是否继续", "请决策", "请审批", "已为您生成以下操作卡",
		}
		for _, p := range patterns {
			if strings.Contains(lower, p) {
				return true
			}
		}
	}
	return false
}

// isCasualOrVeryShort 判断是否属于无长久沉淀价值的极短寒暄
func isCasualOrVeryShort(content string) bool {
	runes := []rune(content)
	if len(runes) <= 12 {
		shortGreetings := []string{
			"好的", "没问题", "收到", "您好", "在的", "请稍候", "不用谢", "再见", "明白",
		}
		for _, g := range shortGreetings {
			if strings.Contains(content, g) {
				return true
			}
		}
	}
	return false
}