session_freshness.go RawHistoryFolder

1package agent
2
3import (
4	"context"
5	"errors"
6	"fmt"
7	"os"
8
9	"github.com/bnema/zut/packages/core"
10	"github.com/bnema/zut/packages/provider"
11)
12
13// openOrCreateSessionState distinguishes creation from restoration even when
14// the restored transcript is empty. Fresh runs may preload pinned skills.
15func openOrCreateSessionState(ctx context.Context, args Args, r Resolved, ag *core.Agent, version string) (*core.Session, bool, error) {
16	if args.NoSess {
17		ag.SessionID()
18		return nil, true, nil
19	}
20	root := agentSessionsRoot(ZutHome(), args)
21	// Explicit paths and UUIDs may identify empty sessions. Don't delete them
22	// before deciding whether this is a restoration.
23	if args.ResumeSessionID == "" && args.Session == "" {
24		core.PruneEmptySessions(root, args.CWD)
25	}
26	var (
27		sess     *core.Session
28		messages []provider.Message
29		err      error
30		fresh    bool
31	)
32	switch {
33	case args.Session != "":
34		sess, messages, err = core.OpenSession(args.Session)
35		if errors.Is(err, os.ErrNotExist) {
36			sess, err = core.NewSessionAtPath(args.Session, args.CWD, r.Provider, r.Model, version)
37			messages, fresh = nil, true
38		}
39	case args.Continue:
40		if path := core.LatestSession(root, args.CWD); path != "" {
41			sess, messages, err = core.OpenSession(path)
42		}
43	case args.Resume:
44		var path string
45		if args.ResumeSessionID != "" {
46			path, err = core.FindManagedSessionByID(ctx, ZutHome(), args.ResumeSessionID)
47			if err != nil {
48				return nil, false, err
49			}
50			if path == "" {
51				return nil, false, fmt.Errorf("session %q not found", args.ResumeSessionID)
52			}
53		} else {
54			path, err = pickSession(root, args.CWD)
55			if err != nil {
56				return nil, false, err
57			}
58		}
59		if path != "" {
60			sess, messages, err = core.OpenSession(path)
61			if err == nil && args.ResumeSessionID != "" && sess.ID != args.ResumeSessionID {
62				return nil, false, errors.Join(fmt.Errorf("session %q changed during resume", args.ResumeSessionID), sess.Close())
63			}
64		}
65	}
66	if err != nil {
67		return nil, false, err
68	}
69	if sess == nil {
70		sess, err = core.NewSession(root, args.CWD, r.Provider, r.Model, version)
71		if err != nil {
72			return nil, false, err
73		}
74		fresh = true
75	}
76	if err := ag.BindSessionID(sess.Meta.ID); err != nil {
77		return nil, false, errors.Join(err, sess.Close())
78	}
79	ag.SetSessionTimeContext(sess.Meta.Started, sess.Meta.Timezone, sess.Meta.TimezoneOffset)
80	if !fresh {
81		ag.SetMessages(messages)
82		if cumulative, last, err := core.SessionUsageDetail(sess.Path); err == nil {
83			ag.SeedCost(cumulative)
84			ag.SeedLastTurnUsage(last)
85		}
86	}
87	return sess, fresh, nil
88}