package server

import (
	"encoding/json"
	"io"
	"net/http"
	"strings"

	"github.com/x-grk/longpolling-remote-access/internal/proto"
)

// Files on an SSH host through a machine, for the panel's file panes: the
// machine's agent keeps the SSH connection (open gives its id) and runs the
// operations there. Downloads and uploads go in the same pieces as a
// machine's own files.

// POST /api/panel/agents/{id}/sshfs/open - {"ssh": {...}} → {conn, home}.
func (s *Server) handleSSHFSOpen(w http.ResponseWriter, r *http.Request) {
	agentID := r.PathValue("id")
	var in struct {
		SSH *proto.SSHTarget `json:"ssh"`
	}
	if err := json.NewDecoder(http.MaxBytesReader(w, r.Body, 64<<10)).Decode(&in); err != nil || in.SSH == nil {
		writeJSON(w, proto.TaskResult{Error: "не указан хост"})
		return
	}
	if err := s.fillSaved(s.currentAdmin(r).ID, in.SSH); err != nil {
		writeJSON(w, proto.TaskResult{Error: err.Error()})
		return
	}
	t := in.SSH
	t.Host, t.User = strings.TrimSpace(t.Host), strings.TrimSpace(t.User)
	if t.Port == 0 {
		t.Port = 22
	}
	if t.Host == "" || t.User == "" || t.Port < 1 || t.Port > 65535 {
		writeJSON(w, proto.TaskResult{Error: "нужны хост, порт и пользователь"})
		return
	}
	if !s.fsAgent(w, agentID, true) {
		return
	}
	res, err := s.waitTask(r.Context(), agentID, proto.TaskSSHFSOpen, proto.SSHFSArgs{SSH: t}, fsTaskTimeout)
	if err != nil {
		res = proto.TaskResult{Error: err.Error()}
	}
	if unknownOp(res) {
		res = proto.TaskResult{Error: "агент не умеет файлы по SSH - обновите его"}
	}
	if res.OK {
		if admin := s.currentAdmin(r); admin != nil {
			s.db.Audit(admin.ID, agentID, "sshfs.open:"+t.User+"@"+t.Host)
		}
	}
	writeJSON(w, res)
}

// sshfsChanges are the operations that change files, for the audit log.
var sshfsChanges = map[string]bool{"write": true, "mkdir": true, "delete": true, "deltree": true, "move": true, "copy": true, "chmod": true, "zip": true, "unzip": true}

// POST /api/panel/agents/{id}/sshfs/{conn}/{op} - an operation on the host;
// the body is in the shape of the machine's own fs.{op}. "close" drops the
// connection.
func (s *Server) handleSSHFSOp(w http.ResponseWriter, r *http.Request) {
	agentID, conn, op := r.PathValue("id"), r.PathValue("conn"), r.PathValue("op")
	body, err := io.ReadAll(http.MaxBytesReader(w, r.Body, 64<<20))
	if err != nil {
		http.Error(w, "bad request", http.StatusBadRequest)
		return
	}
	if !s.fsAgent(w, agentID, true) {
		return
	}
	task, args := proto.TaskSSHFSOp, proto.SSHFSArgs{Conn: conn, Op: op, Args: json.RawMessage(body)}
	if op == "close" {
		task, args = proto.TaskSSHFSClose, proto.SSHFSArgs{Conn: conn}
	}
	if len(args.Args) == 0 {
		args.Args = json.RawMessage("{}")
	}
	if sshfsChanges[op] {
		var d struct{ Path, Src, Dst string }
		_ = json.Unmarshal(body, &d)
		if admin := s.currentAdmin(r); admin != nil {
			s.db.Audit(admin.ID, agentID, "sshfs."+op+":"+strings.TrimSpace(d.Path+" "+d.Src+" "+d.Dst))
		}
	}
	res, err := s.waitTask(r.Context(), agentID, task, args, fsTaskTimeout)
	if err != nil {
		res = proto.TaskResult{Error: err.Error()}
	}
	if unknownOp(res) && op != "close" {
		res = proto.TaskResult{Error: "агент не умеет файлы по SSH - обновите его"}
	}
	writeJSON(w, res)
}

// GET /api/panel/agents/{id}/sshfs/{conn}/download?path=...[&inline=1]
func (s *Server) handleSSHFSDownload(w http.ResponseWriter, r *http.Request) {
	s.download(w, r, proto.TaskSSHFSSend, r.PathValue("conn"))
}

// POST /api/panel/agents/{id}/sshfs/{conn}/upload?path=...&size=N
func (s *Server) handleSSHFSUpload(w http.ResponseWriter, r *http.Request) {
	if admin := s.currentAdmin(r); admin != nil {
		s.db.Audit(admin.ID, r.PathValue("id"), "sshfs.upload:"+r.URL.Query().Get("path"))
	}
	s.uploadStart(w, r, proto.TaskSSHFSPut, r.PathValue("conn"))
}