package handlers

import (
	"context"
	"encoding/json"
	"fmt"
	"html/template"
	"net/http"
	"net/url"
	"time"

	"github.com/gin-gonic/gin"
	"go.uber.org/zap"

	"tyapi-server/internal/application/api/commands"
	"tyapi-server/internal/domains/api/dto"
	api_repositories "tyapi-server/internal/domains/api/repositories"
	api_services "tyapi-server/internal/domains/api/services"
	"tyapi-server/internal/domains/api/services/processors"
	"tyapi-server/internal/domains/api/services/processors/qygl"
	"tyapi-server/internal/shared/pdf"
)

// QYGLReportHandler 企业全景报告页面渲染处理器
// 使用 QYGLJ1U9 聚合接口生成企业报告数据，并通过模板引擎渲染 qiye.html
type QYGLReportHandler struct {
	apiRequestService *api_services.ApiRequestService
	logger            *zap.Logger

	reportRepo      api_repositories.ReportRepository
	pdfCacheManager *pdf.PDFCacheManager
	qyglPDFPregen   *pdf.QYGLReportPDFPregen
}

// NewQYGLReportHandler 创建企业报告页面处理器
func NewQYGLReportHandler(
	apiRequestService *api_services.ApiRequestService,
	logger *zap.Logger,
	reportRepo api_repositories.ReportRepository,
	pdfCacheManager *pdf.PDFCacheManager,
	qyglPDFPregen *pdf.QYGLReportPDFPregen,
) *QYGLReportHandler {
	return &QYGLReportHandler{
		apiRequestService: apiRequestService,
		logger:            logger,
		reportRepo:        reportRepo,
		pdfCacheManager:   pdfCacheManager,
		qyglPDFPregen:     qyglPDFPregen,
	}
}

// GetQYGLReportPage 企业全景报告页面
// GET /reports/qygl?ent_code=xxx&ent_name=yyy&ent_reg_no=zzz
func (h *QYGLReportHandler) GetQYGLReportPage(c *gin.Context) {
	// 读取查询参数
	entCode := c.Query("ent_code")
	entName := c.Query("ent_name")
	entRegNo := c.Query("ent_reg_no")

	// 组装 QYGLUY3S 入参
	req := dto.QYGLUY3SReq{
		EntName:  entName,
		EntRegno: entRegNo,
		EntCode:  entCode,
	}

	params, err := json.Marshal(req)
	if err != nil {
		h.logger.Error("序列化企业全景报告入参失败", zap.Error(err))
		c.String(http.StatusInternalServerError, "生成企业报告失败，请稍后重试")
		return
	}

	// 通过 ApiRequestService 调用 QYGLJ1U9 聚合处理器
	options := &commands.ApiCallOptions{}
	callCtx := &processors.CallContext{}

	ctx := c.Request.Context()
	respBytes, err := h.apiRequestService.PreprocessRequestApi(ctx, "QYGLJ1U9", params, options, callCtx)
	if err != nil {
		h.logger.Error("调用企业全景报告处理器失败", zap.Error(err))
		c.String(http.StatusInternalServerError, "生成企业报告失败，请稍后重试")
		return
	}

	var report map[string]interface{}
	if err := json.Unmarshal(respBytes, &report); err != nil {
		h.logger.Error("解析企业全景报告结果失败", zap.Error(err))
		c.String(http.StatusInternalServerError, "生成企业报告失败，请稍后重试")
		return
	}

	reportJSONBytes, err := json.Marshal(report)
	if err != nil {
		h.logger.Error("序列化企业全景报告结果失败", zap.Error(err))
		c.String(http.StatusInternalServerError, "生成企业报告失败，请稍后重试")
		return
	}

	// 使用 template.JS 避免在脚本中被转义，直接作为 JS 对象字面量注入
	reportJSON := template.JS(reportJSONBytes)

	c.HTML(http.StatusOK, "qiye.html", gin.H{
		"ReportJSON": reportJSON,
	})
}

// GetQYGLReportPageByID 通过编号查看企业全景报告页面
// GET /reports/qygl/:id
func (h *QYGLReportHandler) GetQYGLReportPageByID(c *gin.Context) {
	id := c.Param("id")
	if id == "" {
		c.String(http.StatusBadRequest, "报告编号不能为空")
		return
	}

	// 优先从数据库中查询报告记录
	if h.reportRepo != nil {
		if entity, err := h.reportRepo.FindByReportID(c.Request.Context(), id); err == nil && entity != nil {
			h.maybeScheduleQYGLPDFPregen(c.Request.Context(), id)
			reportJSON := template.JS(entity.ReportData)
			c.HTML(http.StatusOK, "qiye.html", gin.H{
				"ReportJSON": reportJSON,
			})
			return
		}
	}

	// 回退到进程内存缓存（兼容老的访问方式）
	report, ok := qygl.GetQYGLReport(id)
	if !ok {
		c.String(http.StatusNotFound, "报告不存在或已过期")
		return
	}

	reportJSONBytes, err := json.Marshal(report)
	if err != nil {
		h.logger.Error("序列化企业全景报告结果失败", zap.Error(err))
		c.String(http.StatusInternalServerError, "生成企业报告失败，请稍后再试")
		return
	}

	reportJSON := template.JS(reportJSONBytes)

	h.maybeScheduleQYGLPDFPregen(c.Request.Context(), id)

	c.HTML(http.StatusOK, "qiye.html", gin.H{
		"ReportJSON": reportJSON,
	})
}

// qyglReportExists 报告是否仍在库或本进程内存中（用于决定是否补开预生成）
func (h *QYGLReportHandler) qyglReportExists(ctx context.Context, id string) bool {
	if h.reportRepo != nil {
		if e, err := h.reportRepo.FindByReportID(ctx, id); err == nil && e != nil {
			return true
		}
	}
	_, ok := qygl.GetQYGLReport(id)
	return ok
}

// maybeScheduleQYGLPDFPregen 在已配置公网基址时异步预生成 PDF；Schedule 内部会去重。
// 解决：服务重启 / 多实例后内存队列为空，用户打开报告页或轮询状态时仍应能启动预生成。
func (h *QYGLReportHandler) maybeScheduleQYGLPDFPregen(ctx context.Context, id string) {
	if id == "" || h.qyglPDFPregen == nil || !h.qyglPDFPregen.Enabled() {
		return
	}
	if !h.qyglReportExists(ctx, id) {
		return
	}
	h.qyglPDFPregen.ScheduleQYGLReportPDF(context.Background(), id)
}

// GetQYGLReportPDFStatusByID 查询企业报告 PDF 预生成状态（供前端轮询）
// GET /reports/qygl/:id/pdf/status
func (h *QYGLReportHandler) GetQYGLReportPDFStatusByID(c *gin.Context) {
	id := c.Param("id")
	if id == "" {
		c.JSON(http.StatusBadRequest, gin.H{"status": "none", "message": "报告编号不能为空"})
		return
	}
	if h.pdfCacheManager != nil {
		if b, hit, _, err := h.pdfCacheManager.GetByReportID(id); hit && err == nil && len(b) > 0 {
			c.JSON(http.StatusOK, gin.H{"status": string(pdf.QYGLReportPDFStatusReady), "message": ""})
			return
		}
	}
	if h.qyglPDFPregen == nil || !h.qyglPDFPregen.Enabled() {
		c.JSON(http.StatusOK, gin.H{"status": string(pdf.QYGLReportPDFStatusNone), "message": "未启用预生成，将在下载时现场生成"})
		return
	}
	st, msg := h.qyglPDFPregen.Status(id)
	if st == pdf.QYGLReportPDFStatusNone && h.qyglReportExists(c.Request.Context(), id) {
		h.qyglPDFPregen.ScheduleQYGLReportPDF(context.Background(), id)
		st, msg = h.qyglPDFPregen.Status(id)
	}
	c.JSON(http.StatusOK, gin.H{"status": string(st), "message": userFacingPDFStatusMessage(st, msg)})
}

func userFacingPDFStatusMessage(st pdf.QYGLReportPDFStatus, raw string) string {
	switch st {
	case pdf.QYGLReportPDFStatusPending:
		return "排队生成中"
	case pdf.QYGLReportPDFStatusGenerating:
		return "正在生成 PDF"
	case pdf.QYGLReportPDFStatusFailed:
		if raw != "" {
			return raw
		}
		return "预生成失败，下载时将重新生成"
	case pdf.QYGLReportPDFStatusReady:
		return ""
	case pdf.QYGLReportPDFStatusNone:
		return "尚未开始预生成"
	default:
		return ""
	}
}

// GetQYGLReportPDFByID 通过编号导出企业全景报告 PDF：优先读缓存；可短时等待预生成；否则 headless 现场生成并写入缓存
// GET /reports/qygl/:id/pdf
func (h *QYGLReportHandler) GetQYGLReportPDFByID(c *gin.Context) {
	id := c.Param("id")
	if id == "" {
		c.String(http.StatusBadRequest, "报告编号不能为空")
		return
	}

	var fileName = "企业全景报告.pdf"
	if h.reportRepo != nil {
		if entity, err := h.reportRepo.FindByReportID(c.Request.Context(), id); err == nil && entity != nil {
			if entity.EntName != "" {
				fileName = fmt.Sprintf("%s_企业全景报告.pdf", entity.EntName)
			}
		}
	}

	var pdfBytes []byte
	if h.pdfCacheManager != nil {
		if b, hit, _, err := h.pdfCacheManager.GetByReportID(id); hit && err == nil && len(b) > 0 {
			pdfBytes = b
		}
	}

	// 缓存未命中时：若正在预生成，短时等待（与前端轮询互补）
	if len(pdfBytes) == 0 && h.qyglPDFPregen != nil && h.qyglPDFPregen.Enabled() && h.pdfCacheManager != nil {
		deadline := time.Now().Add(90 * time.Second)
		for time.Now().Before(deadline) {
			st, _ := h.qyglPDFPregen.Status(id)
			if st == pdf.QYGLReportPDFStatusFailed {
				break
			}
			if b, hit, _, err := h.pdfCacheManager.GetByReportID(id); hit && err == nil && len(b) > 0 {
				pdfBytes = b
				break
			}
			time.Sleep(400 * time.Millisecond)
		}
	}

	if len(pdfBytes) == 0 {
		scheme := "http"
		if c.Request.TLS != nil {
			scheme = "https"
		} else if forwardedProto := c.Request.Header.Get("X-Forwarded-Proto"); forwardedProto != "" {
			scheme = forwardedProto
		}
		reportURL := fmt.Sprintf("%s://%s/reports/qygl/%s", scheme, c.Request.Host, id)

		h.logger.Info("现场生成企业全景报告 PDF（headless Chrome）",
			zap.String("report_id", id),
			zap.String("url", reportURL),
		)

		pdfGen := pdf.NewHTMLPDFGenerator(h.logger)
		var err error
		pdfBytes, err = pdfGen.GenerateFromURL(c.Request.Context(), reportURL)
		if err != nil {
			h.logger.Error("生成企业全景报告 PDF 失败", zap.String("report_id", id), zap.Error(err))
			c.String(http.StatusInternalServerError, "生成企业报告 PDF 失败，请稍后重试")
			return
		}
		if len(pdfBytes) == 0 {
			h.logger.Error("生成的企业全景报告 PDF 为空", zap.String("report_id", id))
			c.String(http.StatusInternalServerError, "生成的企业报告 PDF 为空，请稍后重试")
			return
		}
		if h.pdfCacheManager != nil {
			_ = h.pdfCacheManager.SetByReportID(id, pdfBytes)
		}
		if h.qyglPDFPregen != nil {
			h.qyglPDFPregen.MarkReadyAfterUpload(id)
		}
	}

	encodedFileName := url.QueryEscape(fileName)
	c.Header("Content-Type", "application/pdf")
	c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", encodedFileName))
	c.Data(http.StatusOK, "application/pdf", pdfBytes)
}