package squad

import (
	"archive/zip"
	"bytes"
	"encoding/xml"
	"fmt"
	"io"
	"path/filepath"
	"strings"
	"unicode/utf8"
)

// ExtractTextWithAnchors 从不同格式材料中提取纯文本，并自动注入物理页码锚点 <!-- page N -->
func ExtractTextWithAnchors(filename string, data []byte) (string, error) {
	if len(data) == 0 {
		return "", nil
	}

	ext := strings.ToLower(filepath.Ext(filename))
	switch ext {
	case ".txt", ".md", ".json", ".yaml", ".yml":
		return string(data), nil
	case ".docx":
		txt, err := extractTextFromDOCX(data)
		if err == nil && len(strings.TrimSpace(txt)) > 0 {
			return injectPageAnchorsForText(txt), nil
		}
		// 降级：从二进制中提取可见字符
		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
	default:
		// 通用降级
		return injectPageAnchorsForText(extractAsciiUtf8Strings(data)), nil
	}
}

// injectPageAnchorsForText 将连续文本按约 1200 字符切分，并注入 <!-- page N --> 锚点
func injectPageAnchorsForText(raw string) string {
	raw = strings.TrimSpace(raw)
	if raw == "" {
		return ""
	}

	// 若原始文本中包含换页符 \f
	if strings.Contains(raw, "\f") {
		pages := strings.Split(raw, "\f")
		var sb strings.Builder
		for i, page := range pages {
			pTrim := strings.TrimSpace(page)
			if pTrim == "" {
				continue
			}
			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n%s\n", i+1, pTrim))
		}
		return strings.TrimSpace(sb.String())
	}

	// 否则按段落累加约 1200 字符为一页
	paragraphs := strings.Split(raw, "\n")
	var sb strings.Builder
	currentPage := 1
	currentLen := 0

	sb.WriteString(fmt.Sprintf("<!-- page %d -->\n", currentPage))
	for _, p := range paragraphs {
		pTrim := strings.TrimRight(p, "\r\t ")
		pLen := utf8.RuneCountInString(pTrim)
		if currentLen > 0 && currentLen+pLen > 1200 {
			currentPage++
			sb.WriteString(fmt.Sprintf("\n<!-- page %d -->\n", currentPage))
			currentLen = 0
		}
		sb.WriteString(pTrim)
		sb.WriteString("\n")
		currentLen += pLen + 1
	}

	return strings.TrimSpace(sb.String())
}

// extractTextFromDOCX 解析 docx 的 word/document.xml 提取段落文本
func extractTextFromDOCX(data []byte) (string, error) {
	r, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
	if err != nil {
		return "", err
	}

	var docFile *zip.File
	for _, f := range r.File {
		if f.Name == "word/document.xml" {
			docFile = f
			break
		}
	}
	if docFile == nil {
		return "", fmt.Errorf("word/document.xml not found in docx")
	}

	rc, err := docFile.Open()
	if err != nil {
		return "", err
	}
	defer rc.Close()

	xmlBytes, err := io.ReadAll(rc)
	if err != nil {
		return "", err
	}

	decoder := xml.NewDecoder(bytes.NewReader(xmlBytes))
	var sb strings.Builder
	inParagraph := false

	for {
		tok, err := decoder.Token()
		if err != nil {
			break
		}
		switch elem := tok.(type) {
		case xml.StartElement:
			if elem.Name.Local == "p" {
				inParagraph = true
			} else if elem.Name.Local == "br" {
				for _, attr := range elem.Attr {
					if attr.Name.Local == "type" && attr.Value == "page" {
						sb.WriteString("\f")
					}
				}
			} else if elem.Name.Local == "lastRenderedPageBreak" {
				sb.WriteString("\f")
			}
		case xml.EndElement:
			if elem.Name.Local == "p" {
				if inParagraph {
					sb.WriteString("\n")
					inParagraph = false
				}
			}
		case xml.CharData:
			sb.Write(elem)
		}
	}

	return sb.String(), nil
}

// extractAsciiUtf8Strings 降级算法：从二进制流中提取连续的有效可读 UTF-8 文本
func extractAsciiUtf8Strings(data []byte) string {
	var sb strings.Builder
	var cur bytes.Buffer

	flush := func() {
		if cur.Len() >= 4 {
			s := cur.String()
			s = strings.TrimSpace(s)
			if s != "" {
				sb.WriteString(s)
				sb.WriteString("\n")
			}
		}
		cur.Reset()
	}

	for i := 0; i < len(data); {
		r, size := utf8.DecodeRune(data[i:])
		if size > 0 && r != utf8.RuneError && (r >= 32 || r == '\n' || r == '\t' || r == '\r') {
			cur.WriteRune(r)
			i += size
		} else {
			flush()
			i++
		}
	}
	flush()

	return sb.String()
}

// ExtractAdvisorBriefing 从 output.md 与黑板事实中提取 B 轨业务参谋决策锦囊
func ExtractAdvisorBriefing(taskKey string, markdownBody string, fields map[string]string) *AdvisorBriefing {
	if fields == nil {
		fields = make(map[string]string)
	}

	projectName := fields["project_name"]
	customerName := fields["customer_name"]
	deviceType := fields["device_type"]
	if projectName == "" {
		projectName = "本项目"
	}
	if customerName == "" {
		customerName = "客户"
	}
	if deviceType == "" {
		deviceType = "医疗器械"
	}

	brief := &AdvisorBriefing{
		MaturityScore:       60,
		MaturityLevel:       "V0.1",
		MaturityHeadline:    "已提取基础事实框架，关键技术与商务参数已按行业基准预设",
		BaselineAssumptions: []string{},
		PreemptiveRisks:     []string{},
		NextBestActions:     []string{},
		CommunicationKit:    "",
	}

	// 1. 扫描文档提取待确认项与假定
	lines := strings.Split(markdownBody, "\n")
	inPendingSection := false
	var pendingItems []string

	for _, line := range lines {
		trim := strings.TrimSpace(line)
		if strings.HasPrefix(trim, "## 待确认清单") {
			inPendingSection = true
			continue
		}
		if inPendingSection && strings.HasPrefix(trim, "## ") {
			inPendingSection = false
		}
		if inPendingSection {
			if strings.HasPrefix(trim, "- ") || strings.HasPrefix(trim, "* ") {
				item := strings.TrimLeft(trim, "-* ")
				if len(item) > 3 && !strings.HasPrefix(item, "（逐条") {
					pendingItems = append(pendingItems, item)
				}
			}
		}
	}

	// 2. 根据任务类型与提取事实定制成熟度、风险与话术
	switch taskKey {
	case "intake", "user_requirements":
		brief.MaturityScore = 65
		brief.MaturityLevel = "V0.1"
		brief.MaturityHeadline = fmt.Sprintf("已完成「%s」的初始事实沉淀，当前具备进入方案与法规初筛的基准条件", projectName)
		brief.BaselineAssumptions = []string{
			"硬件与模具研发暂按国内 ISO 13485 标准 CDMO 体系工程规范核算",
			"临床评价路径暂按免临床评价/同品种对比做基准成本估算",
			"软件若涉及 AI 或算法质控，暂假定数据不出域、私有化部署",
		}
		brief.PreemptiveRisks = []string{
			"若客户宣称中包含实质性疗效或治疗作用，可能触发器械分类升档（如二类转三类），研发与注册周期将增加 6-12 个月",
			"时间与预算尚缺客户书面口径，直接对外报价存在后续争议风险",
		}
		brief.NextBestActions = []string{
			"使用下方微信话术与客户负责人核实 3 个关键事实口径",
			"同意当前基准假设，直接触发 V0.5 阶段（方案成型与法规对齐）",
			"上传新的客户沟通纪要或补充材料进行局部刷新",
		}

		topClarifications := "1. 目标注册区域是否锁定中国 NMPA；\n2. 期望的样机测试与立项交付节点；\n3. 是否有指定采购的元器件品牌或特定工艺要求。"
		if len(pendingItems) > 0 {
			var picked []string
			for _, pi := range pendingItems {
				if len(picked) >= 3 {
					break
				}
				if len(pi) > 100 {
					pi = pi[:100] + "..."
				}
				picked = append(picked, pi)
			}
			topClarifications = ""
			for idx, p := range picked {
				topClarifications += fmt.Sprintf("%d. %s\n", idx+1, p)
			}
		}

		brief.CommunicationKit = fmt.Sprintf(
			"【建议发送给 %s 负责人的微信沟通草稿】\n"+
				"----------------------------------------\n"+
				"您好！关于「%s」的立项需求，我们小队已基于您此前提供的资料做了梳理，搭建了一版立项需求与方案底表。\n\n"+
				"为了方便我们后续为您更精准地测算开发周期和成本，想向您请教并确认几个核心细节：\n"+
				"%s\n"+
				"您可以随时语音或文字简单告知，我们随时跟进更新！\n"+
				"----------------------------------------",
			customerName, projectName, topClarifications,
		)

	case "research", "feasibility_reg", "feasibility_dev", "prelim_design":
		brief.MaturityScore = 80
		brief.MaturityLevel = "V0.5"
		brief.MaturityHeadline = fmt.Sprintf("「%s」的设计方案框架与法规路径已成型，已具备进行详细 WBS 拆解与报价的条件", projectName)
		brief.BaselineAssumptions = []string{
			"系统架构采用模块化分层设计，软硬件接口保持独立兼容",
			"电气安全与电磁兼容暂按 GB 9706.1-2020 / YY 0505 标准预留检测整改预算",
			"关键物料与传感器优先考虑国内成熟供应链以确保交付周期可控",
		}
		brief.PreemptiveRisks = []string{
			"关键元器件交付周期可能受供应链波动影响，建议首期备料周期预留 4 周冗余",
			"新国标实施对型式检验提出更严格要求，需警惕实验室排队时间窗口",
		}
		brief.NextBestActions = []string{
			"审阅初步系统架构图与法规分类论证说明",
			"进入 V1.0 商业锁定阶段，生成明细 CDO 报价单与 Excel 核算模型",
		}
		brief.CommunicationKit = fmt.Sprintf(
			"【建议发送给 %s 的方案汇报提纲】\n"+
				"----------------------------------------\n"+
				"您好！关于「%s」，我们已完成了技术路线比选与法规路径分析：\n"+
				"1. 系统初步架构及子模块边界已清晰，推荐选用高成熟度国产供应链方案；\n"+
				"2. 注册路径与检验标准已完成梳理，预计整体开发与型检周期可控；\n"+
				"我们正在为您生成精细化的 CDO 工时与成本核算表，如有最新调整敬请告知。\n"+
				"----------------------------------------",
			customerName, projectName,
		)

	case "cdo_quote":
		brief.MaturityScore = 95
		brief.MaturityLevel = "V1.0"
		brief.MaturityHeadline = fmt.Sprintf("「%s」已完成全模块 WBS 工时拆解与成本测算，具备合同签约与立项启动条件", projectName)
		brief.BaselineAssumptions = []string{
			"按水木东方标准 CDMO 研发工时单价模型测算，包含设计、工艺、质量与项目管理全环节",
			"第三方注册检测规费按当前国家认可实验室公允价格预留",
		}
		brief.PreemptiveRisks = []string{
			"客户中途若增加子功能或改动工业设计外壳，会直接影响模具及结构费用，合同需设变更保护条款",
		}
		brief.NextBestActions = []string{
			"下载并审阅 CDO报价核算-V01.xlsx 明细表",
			"根据谈判空间决策是否给予商务折扣优惠",
			"确认并锁定项目立项任务书与商务合同草稿",
		}
		brief.CommunicationKit = fmt.Sprintf(
			"【商务报价呈送微信/邮件草稿】\n"+
				"----------------------------------------\n"+
				"尊敬的 %s 领导：\n"+
				"您好！关于「%s」的 CDMO 研发与制造服务方案，我们技术与商务团队已完成最终核算：\n"+
				"附件为详细报价核算明细表，涵盖从设计输入、详细工程开发、样品试制到注册检验的全流程工时分解。\n"+
				"期待与您进一步探讨商务细节，预祝合作顺利！\n"+
				"----------------------------------------",
			customerName, projectName,
		)

	default:
		brief.MaturityScore = 70
		brief.MaturityLevel = "V0.5"
		brief.MaturityHeadline = fmt.Sprintf("已完成任务「%s」的阶段交付与事实沉淀", taskKey)
		brief.NextBestActions = []string{"审阅产出正文", "推进到下一阶段"}
	}

	return brief
}