| 🛟 Updated. 28d5985 k33g 17h ago | 1 | // Permission dialogs: the agent asking before it acts, answered by a person. |
| 2 | |
| 3 | package app |
| 4 | |
| 5 | import ( |
| 6 | "strings" |
| 7 | "sync" |
| 8 | |
| 📦 Turbo Core f3ade8d k33g 9h ago | 9 | "rickub.com/turbo-editors/turbo-core/acp" |
| 10 | "rickub.com/turbo-editors/turbo-core/ui" |
| 🛟 Updated. 28d5985 k33g 17h ago | 11 | ) |
| 12 | |
| 13 | // pendingPermissions is a queue of agents waiting for an answer. |
| 14 | // |
| 15 | // It is a queue with a lock rather than a field, because it is written from |
| 16 | // each session's reading goroutine and read by the event loop. The dialog |
| 17 | // itself is never opened there: opening one belongs to the goroutine that |
| 18 | // draws, which is why the request is only *recorded* here and acted on by |
| 19 | // askNextPermission on the next turn of the loop. |
| 20 | // |
| 21 | // This is the fourth time this project has reached that conclusion — autosave, |
| 22 | // the language server's re-announcement and the terminal's redraws are the |
| 23 | // others — and the reason is always the same: PostEvent is allowed to drop |
| 24 | // what does not fit, so an event may cause a turn of the loop but must never |
| 25 | // be the only thing carrying a fact. |
| 26 | type pendingPermissions struct { |
| 27 | mu sync.Mutex |
| 28 | waiting []*acp.Permission |
| 29 | asking bool // a dialog is up; the next one waits for it |
| 30 | } |
| 31 | |
| 32 | // add records a request and asks the event loop to come round. |
| 33 | func (p *pendingPermissions) add(permission *acp.Permission) { |
| 34 | p.mu.Lock() |
| 35 | defer p.mu.Unlock() |
| 36 | p.waiting = append(p.waiting, permission) |
| 37 | } |
| 38 | |
| 39 | // take returns the next request to ask about, if there is one and no dialog is |
| 40 | // already up. |
| 41 | func (p *pendingPermissions) take() *acp.Permission { |
| 42 | p.mu.Lock() |
| 43 | defer p.mu.Unlock() |
| 44 | |
| 45 | if p.asking || len(p.waiting) == 0 { |
| 46 | return nil |
| 47 | } |
| 48 | next := p.waiting[0] |
| 49 | p.waiting = p.waiting[1:] |
| 50 | p.asking = true |
| 51 | return next |
| 52 | } |
| 53 | |
| 54 | // done says the dialog has closed, so the next request may be asked about. |
| 55 | func (p *pendingPermissions) done() { |
| 56 | p.mu.Lock() |
| 57 | defer p.mu.Unlock() |
| 58 | p.asking = false |
| 59 | } |
| 60 | |
| 61 | // drain removes every waiting request and returns them, for a session going |
| 62 | // away. |
| 63 | func (p *pendingPermissions) drain() []*acp.Permission { |
| 64 | p.mu.Lock() |
| 65 | defer p.mu.Unlock() |
| 66 | |
| 67 | out := p.waiting |
| 68 | p.waiting = nil |
| 69 | return out |
| 70 | } |
| 71 | |
| 72 | // recordPermission is what a session calls when its agent asks to act. |
| 73 | // |
| 74 | // It runs on the session's reading goroutine, so it does exactly two things: |
| 75 | // remembers the request, and wakes the loop. |
| 76 | func (a *App) recordPermission(permission *acp.Permission) { |
| 77 | a.permissions.add(permission) |
| 78 | a.wake() |
| 79 | } |
| 80 | |
| 81 | // askNextPermission opens a dialog for the next agent waiting on an answer. |
| 82 | // |
| 83 | // It runs on every turn of the event loop and does nothing until there is one, |
| 84 | // which is what makes it state-driven rather than event-driven. |
| 85 | func (a *App) askNextPermission() { |
| 86 | permission := a.permissions.take() |
| 87 | if permission == nil { |
| 88 | return |
| 89 | } |
| 90 | if len(permission.Options) == 0 { |
| 91 | // An agent that asks a question with no answers has asked nothing. |
| 92 | permission.Cancel() |
| 93 | a.permissions.done() |
| 94 | return |
| 95 | } |
| 96 | |
| 97 | chosen := new(string) |
| 98 | dialog := a.permissionDialog(permission, chosen) |
| 99 | a.pushModal(dialog, func(ui.Result) { |
| 100 | a.answerPermission(permission, *chosen) |
| 101 | }) |
| 102 | } |
| 103 | |
| 104 | // permissionDialog builds the box, with one button per answer the agent |
| 105 | // offered. Each button carries its own option id, because the agent decides |
| 106 | // what the answers are and an id it does not know is as useless as silence. |
| 107 | // |
| 108 | // A choice is recorded into chosen rather than returned through ui.Result: |
| 109 | // that is an outcome — OK, Cancel, No — and not a number, so it cannot say |
| 110 | // which of four buttons was pressed. |
| 111 | func (a *App) permissionDialog(permission *acp.Permission, chosen *string) *ui.Dialog { |
| 112 | screen := a.screenRect() |
| 113 | width := permissionWidth(permission, screen.W) |
| 114 | |
| 115 | lines := permissionLines(permission, width) |
| 116 | height := len(lines) + 6 |
| 117 | |
| 118 | dialog := ui.NewDialog("Agent") |
| 119 | dialog.SetBounds(ui.Rect{W: width, H: height}.CenteredIn(screen)) |
| 120 | |
| 121 | for i, line := range lines { |
| 122 | label := ui.NewLabel(line) |
| 123 | label.SetBounds(dialog.Layout(3, 2+i, width-6, 1)) |
| 124 | dialog.Add(label) |
| 125 | } |
| 126 | |
| 127 | for i, button := range permissionButtons(dialog, permission, chosen) { |
| 128 | label := permission.Options[i].Name |
| 129 | button.SetBounds(dialog.Layout(buttonX(permission, i, width), height-3, ui.ButtonWidth(label), 1)) |
| 130 | dialog.Add(button) |
| 131 | } |
| 132 | return dialog |
| 133 | } |
| 134 | |
| 135 | // permissionWidth is wide enough for every button the agent offered, and for |
| 136 | // the command a person has to judge — but never wider than the screen. |
| 137 | // |
| 138 | // A fixed width clipped the third of three buttons to "Skip t", which is a |
| 139 | // button whose meaning you cannot read, on a dialog about running a command. |
| 140 | func permissionWidth(permission *acp.Permission, screenWidth int) int { |
| 141 | const minimum = 48 |
| 142 | |
| 143 | wanted := max(buttonsWidth(permission)+6, minimum) |
| 144 | return min(wanted, max(screenWidth-4, minimum)) |
| 145 | } |
| 146 | |
| 147 | // buttonsWidth is how much room the row of buttons needs, gaps included. |
| 148 | func buttonsWidth(permission *acp.Permission) int { |
| 149 | total := 0 |
| 150 | for i, option := range permission.Options { |
| 151 | if i > 0 { |
| 152 | total += buttonGap |
| 153 | } |
| 154 | total += ui.ButtonWidth(option.Name) |
| 155 | } |
| 156 | return total |
| 157 | } |
| 158 | |
| 159 | // buttonGap is the space between two buttons. |
| 160 | const buttonGap = 2 |
| 161 | |
| 162 | // permissionLines are what the box says: the tool, and what it would do. |
| 163 | func permissionLines(permission *acp.Permission, width int) []string { |
| 164 | title := permission.Title |
| 165 | if title == "" { |
| 166 | title = "The agent wants to act" |
| 167 | } |
| 168 | |
| 169 | lines := []string{trimTo(title, width-6)} |
| 170 | if permission.Detail != "" { |
| 171 | lines = append(lines, "", " "+trimTo(permission.Detail, width-8)) |
| 172 | } |
| 173 | return lines |
| 174 | } |
| 175 | |
| 176 | // permissionButtons builds one button per option, in the agent's own order. |
| 177 | // |
| 178 | // The first is the default, because an agent lists its least surprising answer |
| 179 | // first — "allow once" before "allow always" before "reject". |
| 180 | func permissionButtons(dialog *ui.Dialog, permission *acp.Permission, chosen *string) []*ui.Button { |
| 181 | buttons := make([]*ui.Button, len(permission.Options)) |
| 182 | for i, option := range permission.Options { |
| 183 | id := option.OptionID |
| 184 | buttons[i] = ui.NewButton(option.Name, func() { |
| 185 | *chosen = id |
| 186 | dialog.Close(ui.ResultOK) |
| 187 | }) |
| 188 | } |
| 189 | if len(buttons) > 0 { |
| 190 | buttons[0].Default = true |
| 191 | } |
| 192 | return buttons |
| 193 | } |
| 194 | |
| 195 | // buttonX is where one button sits on the row, the whole row centred. |
| 196 | func buttonX(permission *acp.Permission, at, width int) int { |
| 197 | x := max((width-buttonsWidth(permission))/2, 1) |
| 198 | for i := 0; i < at; i++ { |
| 199 | x += ui.ButtonWidth(permission.Options[i].Name) + buttonGap |
| 200 | } |
| 201 | return x |
| 202 | } |
| 203 | |
| 204 | // answerPermission tells the agent what was chosen. |
| 205 | // |
| 206 | // Escape, and anything else that closes the box without a choice, is the |
| 207 | // agent's own "no" rather than a cancellation: the turn is still running, and |
| 208 | // the agent is entitled to carry on without whatever it asked for. |
| 209 | func (a *App) answerPermission(permission *acp.Permission, chosen string) { |
| 210 | defer a.permissions.done() |
| 211 | |
| 212 | if chosen == "" { |
| 213 | permission.Answer(permission.RejectOption()) |
| 214 | return |
| 215 | } |
| 216 | permission.Answer(chosen) |
| 217 | } |
| 218 | |
| 219 | // dropPermissionsOf cancels whatever a session was waiting on, because its |
| 220 | // window is going away. |
| 221 | // |
| 222 | // Cancelled, not refused: nobody declined anything, the conversation simply |
| 223 | // ended. The distinction is the protocol's own, and an agent that logs why it |
| 224 | // stopped should log the truth. |
| 225 | func (a *App) dropPermissionsOf(*acp.Session) { |
| 226 | for _, permission := range a.permissions.drain() { |
| 227 | permission.Cancel() |
| 228 | } |
| 229 | } |
| 230 | |
| 231 | // permissionSummary describes what is waiting, for the status bar. |
| 232 | func (a *App) permissionSummary() string { |
| 233 | a.permissions.mu.Lock() |
| 234 | defer a.permissions.mu.Unlock() |
| 235 | |
| 236 | if len(a.permissions.waiting) == 0 { |
| 237 | return "" |
| 238 | } |
| 239 | |
| 240 | titles := make([]string, 0, len(a.permissions.waiting)) |
| 241 | for _, permission := range a.permissions.waiting { |
| 242 | titles = append(titles, permission.Title) |
| 243 | } |
| 244 | return "agent waiting: " + strings.Join(titles, ", ") |
| 245 | } |
| 246 | |
| 247 | // trimTo clips text to a width in runes, so a box-drawing character or an |
| 248 | // accent counts as the one column it takes rather than its several bytes. |
| 249 | func trimTo(text string, width int) string { |
| 250 | runes := []rune(text) |
| 251 | if width < 1 || len(runes) <= width { |
| 252 | return text |
| 253 | } |
| 254 | return string(runes[:width-1]) + "…" |
| 255 | } |