| 1 | package sheets |
| 2 | |
| 3 | import ( |
| 4 | "net/http" |
| 5 | "strconv" |
| 6 | "strings" |
| 7 | |
| 8 | "amadan.net/oficina/sheets/internal/sheets/store" |
| 9 | ) |
| 10 | |
| 11 | // The scriptless table's page size. |
| 12 | // |
| 13 | // Spec §6: the table view is paginated, "because a 200,000-cell tab |
| 14 | // rendered as one HTML table is a several-hundred-megabyte page". These |
| 15 | // two numbers are what stops that. Rows paginate; columns do not, |
| 16 | // because 26 of them is what a person expects to see across and a |
| 17 | // second axis of paging is a lot of navigation for very little. |
| 18 | const ( |
| 19 | tableRowsPerPage = 25 |
| 20 | tableCols = 26 |
| 21 | ) |
| 22 | |
| 23 | // tableCell is one cell in the scriptless view. |
| 24 | // |
| 25 | // Editing carries Raw and painting carries Display, the same split the |
| 26 | // grid makes — the scriptless view is not a lesser view, it is the same |
| 27 | // data without the script. |
| 28 | type tableCell struct { |
| 29 | R, C int |
| 30 | Ref string // A1 notation, for the label a person reads |
| 31 | Raw string |
| 32 | Display string |
| 33 | Editing bool |
| 34 | // Number is true when the COMPUTED value is numeric, which is what |
| 35 | // lets the view right-align it. Alignment is the type signal in a |
| 36 | // spreadsheet, and the grid gets it from Jspreadsheet for free while |
| 37 | // this view has to be told. |
| 38 | // |
| 39 | // It is taken from the computed kind rather than from Raw, because |
| 40 | // `=SUM(B2:B4)` is a formula whose value is a number, and sniffing |
| 41 | // the input string would align the two differently. The server owns |
| 42 | // every string on screen here; it owns this one bit too. |
| 43 | Number bool |
| 44 | // Paint is the cell's formatting, rendered the same way the grid's |
| 45 | // paint.js renders it — same attributes, same custom properties, so |
| 46 | // sheets.css styles both screens from one set of rules. |
| 47 | Paint cellPaint |
| 48 | } |
| 49 | |
| 50 | type tableRow struct { |
| 51 | Number int // the 1-based row number a person sees |
| 52 | Cells []tableCell |
| 53 | } |
| 54 | |
| 55 | // tableView is the page's payload. |
| 56 | type tableView struct { |
| 57 | // MayWrite gates every claim and affordance only an editor can act |
| 58 | // on. handleTable admits anyone who may READ, while |
| 59 | // handleTableWrite 404s a viewer — so without it the page told |
| 60 | // every reader the cells were editable, then refused them. |
| 61 | MayWrite bool |
| 62 | Sheet SheetSummary |
| 63 | Rows []tableRow |
| 64 | Cols []string |
| 65 | Warned []string |
| 66 | View ViewSpec |
| 67 | FilterOps []string |
| 68 | // The same three lists the grid's Format menu is built from, so a |
| 69 | // control this page renders is a value the format route accepts — |
| 70 | // by construction rather than by remembering to edit both. |
| 71 | NumberFormats []numberFormat |
| 72 | FillSwatches []swatch |
| 73 | InkSwatches []swatch |
| 74 | Page int |
| 75 | Pages int |
| 76 | PrevPage int |
| 77 | NextPage int |
| 78 | HasPrev bool |
| 79 | HasNext bool |
| 80 | } |
| 81 | |
| 82 | // handleTable renders a page of a tab as an ordinary HTML table. |
| 83 | // |
| 84 | // Read-only until you ask to edit one cell: ?edit=r,c turns that cell |
| 85 | // into a form. Rendering an input in every cell would be 650 forms a |
| 86 | // page, most of them never touched, and would make the fallback the |
| 87 | // heaviest page in the app. |
| 88 | func (a *App) handleTable(w http.ResponseWriter, r *http.Request) { |
| 89 | s, ok := a.sheetFromURL(w, r) |
| 90 | if !ok { |
| 91 | return |
| 92 | } |
| 93 | h, err := a.openTabFor(s) |
| 94 | if err != nil { |
| 95 | a.fail(w, r, err) |
| 96 | return |
| 97 | } |
| 98 | defer h.Release() |
| 99 | |
| 100 | // The viewer may be absent: a signed-out reader can reach a sheet |
| 101 | // through a share link, and that reader can never write. |
| 102 | mayWrite := false |
| 103 | if actor, okActor := a.actor(r); okActor { |
| 104 | mayWrite = a.mayWrite(s.ID, actor) |
| 105 | } |
| 106 | |
| 107 | page := intParam(r, "page") |
| 108 | if page < 1 { |
| 109 | page = 1 |
| 110 | } |
| 111 | pages := (maxWindowRows + tableRowsPerPage - 1) / tableRowsPerPage |
| 112 | if page > pages { |
| 113 | page = pages |
| 114 | } |
| 115 | editR, editC := parseEdit(r.URL.Query().Get("edit")) |
| 116 | if !mayWrite { |
| 117 | // Read-only expressed as a coordinate no cell can equal, which |
| 118 | // is the same shape the anonymous link view uses. A viewer or |
| 119 | // commenter who types ?edit=0,0 by hand gets the plain table |
| 120 | // rather than a form that would 404 on submit, and the template |
| 121 | // is not trusted to remember the rule. |
| 122 | editR, editC = -1, -1 |
| 123 | } |
| 124 | |
| 125 | first := (page - 1) * tableRowsPerPage |
| 126 | |
| 127 | view := tableView{ |
| 128 | Sheet: s, Page: page, Pages: pages, |
| 129 | PrevPage: page - 1, NextPage: page + 1, |
| 130 | HasPrev: page > 1, HasNext: page < pages, |
| 131 | MayWrite: mayWrite, |
| 132 | // Ranged over in the template, exactly as the grid's Format |
| 133 | // menu ranges over them, so a control this page offers is a |
| 134 | // value handleFormatPost's allowlist accepts. |
| 135 | NumberFormats: numberFormats, |
| 136 | FillSwatches: fillSwatches, |
| 137 | InkSwatches: inkSwatches, |
| 138 | } |
| 139 | for c := 0; c < tableCols; c++ { |
| 140 | view.Cols = append(view.Cols, colLabel(c)) |
| 141 | } |
| 142 | spec := a.loadView(s.TabID) |
| 143 | view.View = spec |
| 144 | view.FilterOps = filterOps |
| 145 | view.Rows = a.tableRowsIn(h, applyView(h, spec, first, tableRowsPerPage), editR, editC) |
| 146 | |
| 147 | view.Warned = warnedCells(h, newPosIndex(h), maxWindowRows, tableCols) |
| 148 | a.render(w, r, "table", onSheet(s, "Table view"), http.StatusOK, view) |
| 149 | } |
| 150 | |
| 151 | // handleTableWrite is the scriptless write path. |
| 152 | // |
| 153 | // It goes through the same store.SetReport and the same hub as the |
| 154 | // grid's JSON endpoint, so an edit made here fans out to every open |
| 155 | // grid exactly like any other. That is the point of routing both |
| 156 | // through one place: a fallback that wrote by a different path would |
| 157 | // drift, and the drift would only show when somebody actually used it. |
| 158 | func (a *App) handleTableWrite(w http.ResponseWriter, r *http.Request) { |
| 159 | s, ok := a.sheetFromURL(w, r) |
| 160 | if !ok { |
| 161 | return |
| 162 | } |
| 163 | actor, okActor := a.actor(r) |
| 164 | if !okActor { |
| 165 | a.forbidden(w, r) |
| 166 | return |
| 167 | } |
| 168 | // sheetFromURL proved the viewer may READ. Writing needs more, and |
| 169 | // a commenter or viewer reaching this route gets the same 404 as a |
| 170 | // stranger. |
| 171 | if !a.mayWrite(s.ID, actor) { |
| 172 | a.notFound(w, r) |
| 173 | return |
| 174 | } |
| 175 | rowIdx, err := strconv.Atoi(r.FormValue("r")) |
| 176 | if err != nil || rowIdx < 0 || rowIdx >= maxWindowRows { |
| 177 | a.notFound(w, r) |
| 178 | return |
| 179 | } |
| 180 | colIdx, err := strconv.Atoi(r.FormValue("c")) |
| 181 | if err != nil || colIdx < 0 || colIdx >= tableCols { |
| 182 | a.notFound(w, r) |
| 183 | return |
| 184 | } |
| 185 | raw := r.FormValue("raw") |
| 186 | if len(raw) > maxRawBytes { |
| 187 | a.badRequest(w, r, http.StatusRequestEntityTooLarge, "Cell input too long.") |
| 188 | return |
| 189 | } |
| 190 | |
| 191 | h, err := a.openTabFor(s) |
| 192 | if err != nil { |
| 193 | a.fail(w, r, err) |
| 194 | return |
| 195 | } |
| 196 | defer h.Release() |
| 197 | |
| 198 | rowID, err := h.EnsureRow(rowIdx) |
| 199 | if err != nil { |
| 200 | a.fail(w, r, err) |
| 201 | return |
| 202 | } |
| 203 | colID, err := h.EnsureCol(colIdx) |
| 204 | if err != nil { |
| 205 | a.fail(w, r, err) |
| 206 | return |
| 207 | } |
| 208 | rep, err := h.SetReport(rowID, colID, raw, actor.ID) |
| 209 | if err != nil { |
| 210 | a.badRequest(w, r, http.StatusBadRequest, "That cell could not be written.") |
| 211 | return |
| 212 | } |
| 213 | a.publishReport(s, h, rep) |
| 214 | |
| 215 | // 303 back to the page you were on, with no ?edit — a POST that |
| 216 | // renders resubmits on reload, and the reload would rewrite the |
| 217 | // cell. |
| 218 | // |
| 219 | // The page number is parsed and re-formatted rather than escaped |
| 220 | // and passed through: it goes into a Location header, and a number |
| 221 | // that came back out as a number cannot carry anything else. |
| 222 | page, err := strconv.Atoi(r.FormValue("page")) |
| 223 | if err != nil || page < 1 { |
| 224 | page = 1 |
| 225 | } |
| 226 | http.Redirect(w, r, "/sheets/"+strconv.FormatUint(s.ID, 10)+ |
| 227 | "/table?page="+strconv.Itoa(page), http.StatusSeeOther) |
| 228 | } |
| 229 | |
| 230 | // openTabFor opens the handle for a sheet's first tab. |
| 231 | func (a *App) openTabFor(s SheetSummary) (*store.Handle, error) { |
| 232 | if a.db == nil || a.sealer == nil { |
| 233 | return nil, errNoSealer |
| 234 | } |
| 235 | return store.Open(a.db, a.sealer, s.TabID) |
| 236 | } |
| 237 | |
| 238 | // parseEdit reads "r,c" from the query. Anything malformed selects no |
| 239 | // cell, which renders the plain read-only table — the safe default. |
| 240 | func parseEdit(v string) (int, int) { |
| 241 | parts := strings.SplitN(v, ",", 2) |
| 242 | if len(parts) != 2 { |
| 243 | return -1, -1 |
| 244 | } |
| 245 | r, err1 := strconv.Atoi(parts[0]) |
| 246 | c, err2 := strconv.Atoi(parts[1]) |
| 247 | if err1 != nil || err2 != nil { |
| 248 | return -1, -1 |
| 249 | } |
| 250 | return r, c |
| 251 | } |
| 252 | |
| 253 | // colLabel turns a zero-based column index into spreadsheet letters: |
| 254 | // 0 -> A, 25 -> Z, 26 -> AA. |
| 255 | func colLabel(n int) string { |
| 256 | label := "" |
| 257 | for n >= 0 { |
| 258 | label = string(rune('A'+n%26)) + label |
| 259 | n = n/26 - 1 |
| 260 | } |
| 261 | return label |
| 262 | } |
| 263 | |
amadan