package httpapi

import (
	"context"
	"errors"
	"net/http"
	"strconv"
	"time"

	"knowledge-governance/internal/dobotaiops"
)

// No raw SQL, source credential, arbitrary tenant or write method crosses this boundary.
type QAOpsReader interface {
	ListRecords(context.Context, dobotaiops.RecordQuery) (dobotaiops.RecordPage, error)
	GetRecord(context.Context, string, string) (dobotaiops.Record, error)
	Available(context.Context) error
	Safety() dobotaiops.SourceSafety
}

func authorizeQAOps(w http.ResponseWriter, r *http.Request) bool {
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Pragma", "no-cache")
	identity, ok := sessionFrom(r.Context())
	if !ok {
		writeJSON(w, http.StatusUnauthorized, map[string]string{"error": "问答运营需要登录后访问"})
		return false
	}
	// Until the employee-data visibility scope is approved, do not widen access
	// to all pre-existing viewers/engineers merely because this endpoint is GET.
	if identity.Role != roleAdmin {
		writeJSON(w, http.StatusForbidden, map[string]string{"error": "尚未配置员工问答可见范围，当前仅管理员可访问"})
		return false
	}
	return true
}

func qaOpsStatus(w http.ResponseWriter, r *http.Request, config Config) {
	if !authorizeQAOps(w, r) {
		return
	}
	state := "disabled"
	code := "source_not_configured"
	warnings := []string{}
	if config.QAOpsEnabled {
		state = "unavailable"
		code = "source_unavailable"
	}
	if config.QAOpsProblem != "" {
		state = "blocked"
		code = "source_configuration_invalid"
	}
	if config.QAOps != nil && config.QAOps.Available(r.Context()) == nil {
		state = "connected"
		code = ""
		safety := config.QAOps.Safety()
		if safety.DatabaseTemp {
			warnings = append(warnings, "database_temp_enabled")
		}
		if !safety.SSL {
			warnings = append(warnings, "database_transport_unencrypted")
		}
	}
	data := map[string]any{"state": state, "code": code, "warnings": warnings, "read_only": true, "source_version": "2.0", "channel": "dingtalk"}
	if mirror, ok := config.QAOps.(qaMirrorSyncStore); ok {
		cache, err := mirror.GetSyncStatus(r.Context())
		if err != nil {
			qaOpsError(w, err)
			return
		}
		data["cache"] = cache
	}
	writeJSON(w, http.StatusOK, map[string]any{"data": data})
}

func listQAOpsRecords(w http.ResponseWriter, r *http.Request, config Config) {
	if !authorizeQAOps(w, r) {
		return
	}
	if config.QAOps == nil || config.QAOpsTenantKey == "" {
		qaOpsError(w, dobotaiops.ErrUnavailable)
		return
	}
	values := r.URL.Query()
	allowed := map[string]bool{"start": true, "end": true, "keyword": true, "cursor": true, "limit": true, "projection": true}
	for _, key := range dobotaiops.QualityFilterKeys {
		allowed[key] = true
	}
	for key, items := range values {
		if !allowed[key] || len(items) != 1 {
			qaOpsError(w, dobotaiops.ErrInvalidQuery)
			return
		}
	}
	window, err := dobotaiops.NewWindow(config.QAOpsTenantKey, values.Get("start"), values.Get("end"), 90*24*time.Hour, config.Now())
	if err != nil {
		qaOpsError(w, err)
		return
	}
	limit := 20
	if raw := values.Get("limit"); raw != "" {
		limit, err = strconv.Atoi(raw)
		if err != nil || limit < 1 || limit > 100 {
			qaOpsError(w, dobotaiops.ErrInvalidQuery)
			return
		}
	}
	filters := map[string]string{}
	for _, key := range dobotaiops.QualityFilterKeys {
		if value := values.Get(key); value != "" {
			filters[key] = value
		}
	}
	if !dobotaiops.ValidQualityFilters(filters) {
		qaOpsError(w, dobotaiops.ErrInvalidQuery)
		return
	}
	mode := values.Get("projection")
	if mode != "" && mode != "summary" && mode != "full" {
		qaOpsError(w, dobotaiops.ErrInvalidQuery)
		return
	}
	projection, err := recordAttribution(r.Context(), config)
	if err != nil {
		qaOpsError(w, err)
		return
	}
	page, err := config.QAOps.ListRecords(r.Context(), dobotaiops.RecordQuery{Window: window, Keyword: values.Get("keyword"), Cursor: values.Get("cursor"), Limit: limit, Summary: mode == "summary", Filters: filters})
	if err != nil {
		qaOpsError(w, err)
		return
	}
	enrichQAPage(&page, projection)
	if err := enrichQAQualityPage(r.Context(), config, &page); err != nil {
		writeQualityError(w, err)
		return
	}
	if mode == "summary" {
		for i := range page.Items {
			page.Items[i] = qaRecordPreview(page.Items[i])
		}
	}
	writeJSON(w, http.StatusOK, map[string]any{"data": page})
}

func getQAOpsRecord(w http.ResponseWriter, r *http.Request, config Config) {
	if !authorizeQAOps(w, r) {
		return
	}
	if config.QAOps == nil || config.QAOpsTenantKey == "" {
		qaOpsError(w, dobotaiops.ErrUnavailable)
		return
	}
	if r.URL.RawQuery != "" {
		qaOpsError(w, dobotaiops.ErrInvalidQuery)
		return
	}
	projection, err := recordAttribution(r.Context(), config)
	if err != nil {
		qaOpsError(w, err)
		return
	}
	item, err := config.QAOps.GetRecord(r.Context(), config.QAOpsTenantKey, r.PathValue("id"))
	if err != nil {
		qaOpsError(w, err)
		return
	}
	enrichQARecord(&item, projection)
	if err := enrichQAQualityRecord(r.Context(), config, &item); err != nil {
		writeQualityError(w, err)
		return
	}
	writeJSON(w, http.StatusOK, map[string]any{"data": item})
}

func qaOpsError(w http.ResponseWriter, err error) {
	status := http.StatusServiceUnavailable
	code := "source_unavailable"
	message := "问答记录当前不可用；本地模式请检查同步状态，原有知识治理功能不受影响"
	if errors.Is(err, errQAOrganization) {
		code = "organization_unavailable"
		message = "通讯录或区域配置读取失败，未将不可用数据伪装成空列，请重试"
	}
	if errors.Is(err, dobotaiops.ErrInvalidQuery) {
		status = http.StatusBadRequest
		code = "invalid_query"
		message = "查询参数无效：请检查时间范围、关键词长度或重新查询后翻页"
	}
	if errors.Is(err, dobotaiops.ErrNotReadOnly) {
		code = "source_not_read_only"
		message = "问答连接权限校验未通过，已阻止读取，请联系管理员"
	}
	if errors.Is(err, dobotaiops.ErrRecordNotFound) {
		status = http.StatusNotFound
		code = "record_not_found"
		message = "未找到当前授权范围内的问答记录"
	}
	writeJSON(w, status, map[string]string{"error": message, "code": code})
}