package server

import (
	"errors"
	"net/http"

	"agent-system-backend/internal/cmdbus"
	"agent-system-backend/internal/store"
)

// commandOperationQuery 把"已记录 operation 的状态查询"落在既有的 owner+project
// 作用域审计查询上（store.ListProjectCommandAudits），不新建通用幂等平台：不加表、
// 不加索引、不引入新的重试语义。命令回执（审计信封）本就是宿主侧的操作记录，
// handler 自己事务/发件箱里的领域操作表（如文档投递 document_render_deliveries）
// 仍由各自领域查询负责。
//
// 诚实边界：
//   - 只有成功落下审计信封的 operation 查得到。审计不可用时总线回 unknown +
//     operationID，但那一行没有落库：这里返回"无记录"，绝不推断"未执行"。
//   - 扫描有界（最近若干页）：超出窗口的旧操作返回无记录，而不是全表扫描。
//   - project_id 是追加时按可信会话快照下来的归属；改绑/删除会话不改写历史归属，
//     与既有项目审计查询同一口径。
type commandOperationQuery struct{ st *store.Store }

const (
	operationLookupPageSize = 100
	operationLookupMaxPages = 20 // 有界扫描：最近 2000 行，超窗即"无记录"
)

func (q commandOperationQuery) LookupOperation(owner, projectID, operationID string) (cmdbus.OperationRecord, bool, error) {
	if q.st == nil || owner == "" || projectID == "" || operationID == "" {
		return cmdbus.OperationRecord{}, false, nil
	}
	var before, cutoff int64
	for page := 0; page < operationLookupMaxPages; page++ {
		rows, resolvedCutoff, next, err := q.st.ListProjectCommandAudits(owner, projectID, before, cutoff, operationLookupPageSize)
		if err != nil {
			return cmdbus.OperationRecord{}, false, err
		}
		cutoff = resolvedCutoff // 首帧固定游标，后续页在同一提交前缀内翻页
		for _, row := range rows {
			if row.Envelope.OperationID != operationID {
				continue
			}
			return cmdbus.OperationRecord{
				OperationID: row.Envelope.OperationID,
				CommandID:   row.Envelope.CommandID,
				State:       row.Envelope.State,
				Time:        row.Envelope.Time,
			}, true, nil
		}
		if next == 0 {
			return cmdbus.OperationRecord{}, false, nil
		}
		before = next
	}
	return cmdbus.OperationRecord{}, false, nil
}

// getCommandOperation 是 unknown 回执的对账入口（R7/KTD6）：
// GET /api/commands/operations/{operationId}?projectId=…
//
// 授权复用既有口径：owner 只取自认证上下文（不读请求参数），projectId 仅用于
// 收窄到该 owner 名下的项目——与 /api/commands/audit 同源，跨租户天然不可见。
// 查不到一律 404：HTTP 层的"没有记录"同样不得被读成"未执行"。
func (s *Server) getCommandOperation(w http.ResponseWriter, r *http.Request) {
	if s.Bus == nil {
		http.Error(w, "commands disabled", http.StatusServiceUnavailable)
		return
	}
	record, err := s.Bus.LookupOperation(s.owner(r), r.URL.Query().Get("projectId"), r.PathValue("operationId"))
	switch {
	case errors.Is(err, cmdbus.ErrOperationScope):
		http.Error(w, "projectId and operationId are required", http.StatusBadRequest)
		return
	case errors.Is(err, cmdbus.ErrOperationQueryUnavailable):
		http.Error(w, "operation query unavailable", http.StatusServiceUnavailable)
		return
	case errors.Is(err, cmdbus.ErrOperationNotRecorded):
		http.Error(w, "no operation record in this scope", http.StatusNotFound)
		return
	case err != nil:
		writeStoreErr(w, err)
		return
	}
	writeJSON(w, http.StatusOK, map[string]any{"operation": record})
}