Remember scroll positions on visited pages

8 files changed, 74 insertions, 23 deletions

diff --git a/src/app.c b/src/app.c
index 21028edc..5ac211f9 100644
--- a/src/app.c
+++ b/src/app.c
@@ -318,7 +318,7 @@ iGmCerts *certs_App(void) {
     return app_.certs;
 }
 
-const iHistory *history_App(void) {
+iHistory *history_App(void) {
     return app_.history;
 }
 
@@ -346,7 +346,9 @@ iBool handleCommand_App(const char *cmd) {
             }
         }
         print_History(d->history);
-        setUrl_DocumentWidget(findChild_Widget(root, "document"), url);
+        iDocumentWidget *doc = findChild_Widget(root, "document");
+        setUrl_DocumentWidget(doc, url);
+        setInitialScroll_DocumentWidget(doc, argLabel_Command(cmd, "scroll") * gap_UI);
     }
     else if (equal_Command(cmd, "document.request.cancelled")) {
         /* TODO: How should cancelled requests be treated in the history? */
diff --git a/src/app.h b/src/app.h
index 23e30ea5..5cb68920 100644
--- a/src/app.h
+++ b/src/app.h
@@ -26,8 +26,8 @@ void        processEvents_App   (enum iAppEventMode mode);
 iBool       handleCommand_App   (const char *cmd);
 void        refresh_App         (void);
 
-iGmCerts *      certs_App       (void);
-const iHistory *history_App     (void);
+iGmCerts *  certs_App       (void);
+iHistory *  history_App     (void);
 
 iAny *      findWidget_App      (const char *id);
 void        addTicker_App       (void (*ticker)(iAny *), iAny *context);
diff --git a/src/gmutil.h b/src/gmutil.h
index 6c1b01ad..d0ed4581 100644
--- a/src/gmutil.h
+++ b/src/gmutil.h
@@ -3,18 +3,26 @@
 #include <the_Foundation/range.h>
 #include <the_Foundation/string.h>
 
-iDeclareType(GmError)
-iDeclareType(Url)
+iDeclareType(GmError) iDeclareType(Url)
 
 /* Response status codes. */
 enum iGmStatusCode {
-    clientSide_GmStatusCode = -100, /* clientside status codes */
+    /* clientside status codes */
+    clientSide_GmStatusCode = -100,
     invalidRedirect_GmStatusCode,
     invalidHeader_GmStatusCode,
     unsupportedMimeType_GmStatusCode,
     failedToOpenFile_GmStatusCode,
     unknownStatusCode_GmStatusCode,
     none_GmStatusCode                      = 0,
+    /* general status code categories */
+    categoryInput_GmStatusCode             = 1,
+    categorySuccess_GmStatusCode           = 2,
+    categoryRedirect_GmStatusCode          = 3,
+    categoryTemporaryFailure_GmStatusCode  = 4,
+    categoryPermanentFailure_GmStatusCode  = 5,
+    categoryClientCertificate_GmStatus     = 6,
+    /* detailed status codes */
     input_GmStatusCode                     = 10,
     sensitiveInput_GmStatusCode            = 11,
     success_GmStatusCode                   = 20,
@@ -35,6 +43,12 @@ enum iGmStatusCode {
     certificateNotValid_GmStatusCode       = 62,
 };
 
+iLocalDef enum iGmStatusCode category_GmStatusCode(enum iGmStatusCode code) {
+    if (code < 0) return 0;
+    if (code < 10) return code;
+    return code / 10;
+}
+
 struct Impl_GmError {
     iChar       icon;
     const char *title;
diff --git a/src/history.c b/src/history.c
index edffd485..ca80ad3f 100644
--- a/src/history.c
+++ b/src/history.c
@@ -11,6 +11,7 @@ static const size_t maxAgeVisited_History_ = 3600 * 24 * 30; /* one month */
 void init_HistoryItem(iHistoryItem *d) {
     initCurrent_Time(&d->when);
     init_String(&d->url);
+    d->scrollY = 0;
 }
 
 void deinit_HistoryItem(iHistoryItem *d) {
@@ -52,13 +53,14 @@ static void writeItems_(const iArray *items, iFile *f) {
         iDate date;
         init_Date(&date, &item->when);
         format_String(line,
-                      "%04d-%02d-%02dT%02d:%02d:%02d %s\n",
+                      "%04d-%02d-%02dT%02d:%02d:%02d %04x %s\n",
                       date.year,
                       date.month,
                       date.day,
                       date.hour,
                       date.minute,
                       date.second,
+                      item->scrollY,
                       cstr_String(&item->url));
         writeData_File(f, cstr_String(line), size_String(line));
     }
@@ -84,18 +86,19 @@ static void loadItems_(iArray *items, iFile *f, double maxAge) {
     iTime          now;
     initCurrent_Time(&now);
     while (nextSplit_Rangecc(&src, "\n", &line)) {
-        int y, m, D, H, M, S;
-        sscanf(line.start, "%04d-%02d-%02dT%02d:%02d:%02d", &y, &m, &D, &H, &M, &S);
+        int y, m, D, H, M, S, scroll = 0;
+        sscanf(line.start, "%04d-%02d-%02dT%02d:%02d:%02d %04x", &y, &m, &D, &H, &M, &S, &scroll);
         if (!y) break;
         iHistoryItem item;
         init_HistoryItem(&item);
+        item.scrollY = scroll;
         init_Time(
             &item.when,
             &(iDate){ .year = y, .month = m, .day = D, .hour = H, .minute = M, .second = S });
         if (maxAge > 0.0 && secondsSince_Time(&now, &item.when) > maxAge) {
             continue; /* Too old. */
         }
-        initRange_String(&item.url, (iRangecc){ line.start + 20, line.end });
+        initRange_String(&item.url, (iRangecc){ line.start + 25, line.end });
         pushBack_Array(items, &item);
     }
 }
@@ -194,7 +197,9 @@ void addUrl_History(iHistory *d, const iString *url ){
 iBool goBack_History(iHistory *d) {
     if (d->stackPos < size_Array(&d->stack) - 1) {
         d->stackPos++;
-        postCommandf_App("open history:1 url:%s", cstr_String(url_History(d, d->stackPos)));
+        postCommandf_App("open history:1 scroll:%d url:%s",
+                         item_History(d)->scrollY,
+                         cstr_String(url_History(d, d->stackPos)));
         return iTrue;
     }
     return iFalse;
diff --git a/src/history.h b/src/history.h
index 4074b1aa..149e6b82 100644
--- a/src/history.h
+++ b/src/history.h
@@ -10,6 +10,7 @@ iDeclareTypeConstruction(HistoryItem)
 struct Impl_HistoryItem {
     iTime   when;
     iString url;
+    int     scrollY; /* unit is gap_UI */
 };
 
 iDeclareType(History)
diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index 7450ba12..dd119e3e 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -5,6 +5,7 @@
 #include "paint.h"
 #include "command.h"
 #include "util.h"
+#include "history.h"
 #include "app.h"
 #include "../gmdocument.h"
 #include "../gmrequest.h"
@@ -91,6 +92,7 @@ struct Impl_DocumentWidget {
     iPtrArray visibleLinks;
     const iGmRun *hoverLink;
     iClick click;
+    int initialScrollY;
     iScrollWidget *scroll;
     iWidget *menu;
     SDL_Cursor *arrowCursor;
@@ -242,6 +244,12 @@ static void updateVisible_DocumentWidget_(iDocumentWidget *d) {
     clear_PtrArray(&d->visibleLinks);
     render_GmDocument(d->doc, visRange, addVisibleLink_DocumentWidget_, d);
     updateHover_DocumentWidget_(d, mouseCoord_Window(get_Window()));
+    /* Remember scroll positions of recently visited pages. */ {
+        iHistoryItem *it = item_History(history_App());
+        if (it) {
+            it->scrollY = d->scrollY / gap_UI;
+        }
+    }
 }
 
 static void updateWindowTitle_DocumentWidget_(const iDocumentWidget *d) {
@@ -300,9 +308,14 @@ static void showErrorPage_DocumentWidget_(iDocumentWidget *d, enum iGmStatusCode
             break;
     }
     setSource_DocumentWidget_(d, src);
+    d->scrollY = 0;
+    d->state = ready_DocumentState;
 }
 
 static void updateSource_DocumentWidget_(iDocumentWidget *d) {
+    if (d->state == ready_DocumentState) {
+        return;
+    }
     /* TODO: Do this in the background. However, that requires a text metrics calculator
        that does not try to cache the glyph bitmaps. */
     const enum iGmStatusCode statusCode = status_GmRequest(d->request);
@@ -384,6 +397,10 @@ void setUrl_DocumentWidget(iDocumentWidget *d, const iString *url) {
     }
 }
 
+void setInitialScroll_DocumentWidget (iDocumentWidget *d, int scrollY) {
+    d->initialScrollY = scrollY;
+}
+
 iBool isRequestOngoing_DocumentWidget(const iDocumentWidget *d) {
     return d->state == fetching_DocumentState || d->state == receivedPartialResponse_DocumentState;
 }
@@ -437,11 +454,14 @@ static void checkResponse_DocumentWidget_(iDocumentWidget *d) {
         return;
     }
     enum iGmStatusCode statusCode = status_GmRequest(d->request);
+    if (statusCode == none_GmStatusCode) {
+        return;
+    }
     if (d->state == fetching_DocumentState) {
         d->state = receivedPartialResponse_DocumentState;
         updateTrust_DocumentWidget_(d);
-        switch (statusCode / 10) {
-            case 1: /* input required */ {
+        switch (category_GmStatusCode(statusCode)) {
+            case categoryInput_GmStatusCode: {
                 iUrl parts;
                 init_Url(&parts, d->url);
                 printf("%s\n", cstr_String(meta_GmRequest(d->request)));
@@ -460,16 +480,17 @@ static void checkResponse_DocumentWidget_(iDocumentWidget *d) {
                                          statusCode == sensitiveInput_GmStatusCode);
                 break;
             }
-            case 2: /* success */
-                d->scrollY = 0;
+            case categorySuccess_GmStatusCode:
+                d->scrollY = d->initialScrollY;
                 reset_GmDocument(d->doc); /* new content incoming */
                 updateSource_DocumentWidget_(d);
                 break;
-            case 3: /* redirect */
+            case categoryRedirect_GmStatusCode:
                 if (isEmpty_String(meta_GmRequest(d->request))) {
                     showErrorPage_DocumentWidget_(d, invalidRedirect_GmStatusCode);
                 }
                 else {
+                    /* TODO: only accept redirects that use gemini protocol */
                     postCommandf_App(
                         "open redirect:1 url:%s",
                         cstr_String(absoluteUrl_String(d->url, meta_GmRequest(d->request))));
@@ -480,18 +501,20 @@ static void checkResponse_DocumentWidget_(iDocumentWidget *d) {
                 if (isDefined_GmError(statusCode)) {
                     showErrorPage_DocumentWidget_(d, statusCode);
                 }
-                else if (statusCode / 10 == 4) {
+                else if (category_GmStatusCode(statusCode) ==
+                         categoryTemporaryFailure_GmStatusCode) {
                     showErrorPage_DocumentWidget_(d, temporaryFailure_GmStatusCode);
                 }
-                else if (statusCode / 10 == 5) {
+                else if (category_GmStatusCode(statusCode) ==
+                         categoryPermanentFailure_GmStatusCode) {
                     showErrorPage_DocumentWidget_(d, permanentFailure_GmStatusCode);
                 }
                 break;
         }
     }
     else if (d->state == receivedPartialResponse_DocumentState) {
-        switch (statusCode) {
-            case success_GmStatusCode:
+        switch (category_GmStatusCode(statusCode)) {
+            case categorySuccess_GmStatusCode:
                 /* More content available. */
                 updateSource_DocumentWidget_(d);
                 break;
@@ -649,7 +672,6 @@ static iBool processEvent_DocumentWidget_(iDocumentWidget *d, const SDL_Event *e
     }
     else if (isCommand_Widget(w, ev, "document.request.finished") &&
              pointerLabel_Command(command_UserEvent(ev), "request") == d->request) {
-        iAssert(d->state == receivedPartialResponse_DocumentState); /* must already have been updated at least once */
         checkResponse_DocumentWidget_(d);
         d->state = ready_DocumentState;
         iReleasePtr(&d->request);
diff --git a/src/ui/documentwidget.h b/src/ui/documentwidget.h
index dfd342af..6b0ea607 100644
--- a/src/ui/documentwidget.h
+++ b/src/ui/documentwidget.h
@@ -6,4 +6,5 @@ iDeclareWidgetClass(DocumentWidget)
 iDeclareObjectConstruction(DocumentWidget)
 
 void    setUrl_DocumentWidget           (iDocumentWidget *, const iString *url);
+void    setInitialScroll_DocumentWidget (iDocumentWidget *, int scrollY); /* set after content received */
 iBool   isRequestOngoing_DocumentWidget (const iDocumentWidget *);
diff --git a/src/ui/text.c b/src/ui/text.c
index 50b3bbab..f562e642 100644
--- a/src/ui/text.c
+++ b/src/ui/text.c
@@ -356,6 +356,7 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
     iChar prevCh = 0;
     for (const char *chPos = text.start; chPos != text.end; ) {
         iAssert(chPos < text.end);
+        const char *currentPos = chPos;
         if (*chPos == 0x1b) {
             /* ANSI escape. */
             chPos++;
@@ -394,7 +395,12 @@ static iRect run_Font_(iFont *d, enum iRunMode mode, iRangecc text, size_t maxLe
         int x2 = x1 + glyph->rect[hoff].size.x;
         /* Out of the allotted space? */
         if (xposLimit > 0 && x2 > xposLimit) {
-            *continueFrom_out = lastWordEnd;
+            if (lastWordEnd != text.start) {
+                *continueFrom_out = lastWordEnd;
+            }
+            else {
+                *continueFrom_out = currentPos; /* forced break */
+            }
             break;
         }
         const SDL_Rect dst = { x1 + glyph->d[hoff].x,