checkpoint

1 files changed, 472 insertions, 0 deletions

diff --git a/ui_box.h b/ui_box.h
new file mode 100644
index 0000000..c19b9dd
--- /dev/null
+++ b/ui_box.h
@@ -0,0 +1,472 @@
+#ifndef BOX_H
+#define BOX_H
+
+// assumes MAX_INPUT_LEN to be set
+//
+// #define MAX_INPUT_LEN 128
+
+#define TEXTBOX_PADDING_X 1
+#define TEXTBOX_BORDER_WIDTH 1
+#define TEXTBOX_MIN_WIDTH TEXTBOX_PADDING_X * 2 + TEXTBOX_BORDER_WIDTH * 2 + 1;
+#define TEXTBOXFROMBOX(Box) \
+    { \
+        .X = Box.X + TEXTBOX_BORDER_WIDTH + TEXTBOX_PADDING_X, \
+        .Y = Box.Y + TEXTBOX_BORDER_WIDTH, \
+        .W = Box.W - TEXTBOX_BORDER_WIDTH * 2 - TEXTBOX_PADDING_X * 2, \
+        .H = Box.H - TEXTBOX_BORDER_WIDTH * 2 \
+    }
+
+void DrawBox(rect Rect, box_characters *Chars);
+void ScrollLeft(rect Text, u32 *TextOffset);
+void ScrollRight(rect Text, u32 *TextOffset);
+void TextBoxDelete(wchar_t* Text, u64 Pos);
+void TextBoxInsert(wchar_t *Input, u32 InputPos, u32 InputLen, wchar_t ch);
+u32 TextBoxKeypress(struct tb_event ev, rect TextR, wchar_t *Text, u32 *TextLenPtr, u32 TextPos, u32 *TextOffsetPtr);
+void TextBoxDrawText(rect TextR, wchar_t *Input, u32 InputLen, u32 TextOffset);
+
+// Draw box along boundaries in Rect with optional Chars.
+void
+DrawBox(rect Rect, box_characters *Chars)
+{
+    wchar_t ur, ru, rd, dr, lr, ud;
+    if (!Chars)
+    {
+        ur = L'╭';
+        ru = L'╯';
+        rd = L'╮';
+        dr = L'╰';
+        lr = L'─';
+        ud = L'│';
+    }
+    else
+    {
+        ur = Chars->ur;
+        ru = Chars->ru;
+        rd = Chars->rd;
+        dr = Chars->dr;
+        lr = Chars->lr;
+        ud = Chars->ud;
+    }
+
+    Rect.H--;
+    Rect.W--;
+
+    tb_printf(Rect.X, Rect.Y, 0, 0, "%lc", ur);
+    for (s32 X = 1; X < Rect.W; X++)
+    {
+        tb_printf(Rect.X + X, Rect.Y, 0, 0, "%lc", lr);
+    }
+    tb_printf(Rect.X + Rect.W, Rect.Y, 0, 0, "%lc", rd);
+
+    // Draw vertical bars
+    for (s32 Y = 1; Y < Rect.H; Y++)
+    {
+        tb_printf(Rect.X, Rect.Y + Y, 0, 0, "%lc", ud);
+        tb_printf(Rect.X + Rect.W, Rect.Y + Y, 0, 0, "%lc", ud);
+    }
+
+    tb_printf(Rect.X, Rect.Y + Rect.H, 0, 0, "%lc", dr);
+    for (s32 X = 1; X < Rect.W; X++)
+    {
+        tb_printf(Rect.X + X, Rect.Y + Rect.H, 0, 0, "%lc", lr);
+    }
+    tb_printf(Rect.X + Rect.W, Rect.Y + Rect.H, 0, 0, "%lc", ru);
+}
+
+// SCROLLING
+// ╭──────────╮    ╭──────────╮ Going Left on the first character scrolls up.
+// │ █3     4 │ => │ 1     2█ │ Cursor on end of the top line.
+// │  5     6 │    │  3     4 │ 
+// ╰──────────╯    ╰──────────╯
+//
+// ╭──────────╮    ╭──────────╮ Going Right on the last character scrolls down.
+// │ 1      3 │ => │ 2     4  │ Puts cursor on start of the bottom line.
+// │ 2     4█ │    │ █        │ 
+// ╰──────────╯    ╰──────────╯
+//
+// ╭──────────╮    ╭──────────╮ Going Down on bottom line scrolls down.
+// │ 1      3 │ => │ 2      4 │ Cursor stays on bottom line.
+// │ 2  █   4 │    │    █     │ 
+// ╰──────────╯    ╰──────────╯
+//
+// ╭──────────╮    ╭──────────╮ Going Up on top line scrolls up.
+// │ 3  █   4 │ => │ 1  █   2 │ Cursor stays on top line.
+// │ 5      6 │    │ 3      5 │ 
+// ╰──────────╯    ╰──────────╯
+//
+// In code this translates to changing global.cursor_{x,y} and TextOffset accordingly.
+
+// Scroll one character to the left
+void
+TextBoxScrollLeft(rect Text, u32 *TextOffset)
+{
+    // If text is on the first character of the box scroll up
+    if (global.cursor_x == Text.X &&
+        global.cursor_y == Text.Y)
+    {
+        global.cursor_x = Text.X + Text.W - 1;
+        global.cursor_y = Text.Y;
+
+        *TextOffset -= Text.W;
+    }
+    else
+    {
+        if (global.cursor_x == Text.X)
+        {
+            // Got to previous line
+            global.cursor_x = Text.X + Text.W - 1;
+            global.cursor_y--;
+        }
+        else
+        {
+            global.cursor_x--;
+        }
+    }
+}
+
+// Scroll one character to the right
+void
+TextBoxScrollRight(rect Text, u32 *TextOffset)
+{
+    // If cursor is on the last character scroll forwards
+    if (global.cursor_x == Text.X + Text.W - 1 &&
+        global.cursor_y == Text.Y + Text.H - 1)
+    {
+        global.cursor_x = Text.X;
+        global.cursor_y = Text.Y + Text.H - 1;
+
+        *TextOffset += Text.W;
+    }
+    else
+    {
+        global.cursor_x++;
+        if (global.cursor_x == Text.X + Text.W)
+        {
+            global.cursor_x = Text.X;
+            global.cursor_y++;
+        }
+    }
+}
+
+
+// Delete a character in Text at Pos
+void
+TextBoxDelete(wchar_t* Text, u64 Pos)
+{
+    memmove(Text + Pos,
+            Text + Pos + 1,
+            (MAX_INPUT_LEN - Pos - 1) * sizeof(*Text));
+}
+
+// Insert a ev.ch in Input at InputPos
+void
+TextBoxInsert(wchar_t *Input, u32 InputPos, u32 InputLen, wchar_t ch)
+{
+    if (InputPos < InputLen)
+    {
+        memmove(Input + InputPos,
+                Input + InputPos - 1,
+                (InputLen - InputPos + 1) * sizeof(*Input));
+    }
+    Input[InputPos] = ch;
+}
+
+// Handle the key event and edit Input and updates TextLenPtr and TextOffsetPtr accordingly.
+// InputPos is the position in the Input relating to the cursor position.
+// TextR is the bounding box for the text.
+// Returns 0 no key event was handled
+u32
+TextBoxKeypress(struct tb_event ev, rect TextR,
+                wchar_t *Text, u32 *TextLenPtr, u32 TextPos, u32 *TextOffsetPtr)
+{
+    u32 Result = 1;
+
+    u32 TextLen = *TextLenPtr;
+    u32 TextOffset = *TextOffsetPtr;
+
+    switch (ev.key)
+    {
+
+    // Delete character backwards
+    case TB_KEY_CTRL_8:
+    // case TB_KEY_BACKSPACE2:
+    {
+        if (TextPos == 0) break;
+
+        TextBoxDelete(Text, TextPos - 1);
+        TextLen--;
+
+        TextBoxScrollLeft(TextR, &TextOffset);
+
+    } break;
+
+    // Delete character forwards
+    case TB_KEY_CTRL_D:
+    {
+        if (TextPos == TextLen) break;
+        TextBoxDelete(Text, TextPos);
+        TextLen--;
+        // Delete(Text, Position)
+    } break;
+
+    // Delete word backwards
+    case TB_KEY_CTRL_W:
+    {
+        u32 At = TextPos;
+        // Find character to stop on
+        while (At && is_whitespace(Text[At - 1])) At--;
+        while (At && !is_whitespace(Text[At - 1])) At--;
+
+        s32 NDelete = TextPos - At;
+        memmove(Text + At, Text + TextPos, (TextLen - TextPos) * sizeof(Text[At]));
+        TextLen -= NDelete;
+#ifdef DEBUG
+        Text[TextLen] = 0;
+#endif
+        // NOTE: this could be calculated at once instead
+        while(NDelete--) TextBoxScrollLeft(TextR, &TextOffset);
+
+        Assert(IsInRect(TextR, global.cursor_x, global.cursor_y));
+
+    } break;
+
+    // Delete until start of Text
+    case TB_KEY_CTRL_U:
+    {
+        memmove(Text, Text + TextPos, (TextLen - TextPos) * sizeof(*Text));
+        TextLen -= TextPos;
+#ifdef DEBUG
+        Text[TextLen] = 0;
+#endif
+        global.cursor_x = TextR.X;
+        global.cursor_y = TextR.Y;
+        TextOffset = 0;
+    } break;
+
+    // Delete until end of Text
+    case TB_KEY_CTRL_K:
+    {
+        TextLen = TextPos;
+        Text[TextPos] = 0;
+    } break;
+
+    // Move to start of line
+    case TB_KEY_CTRL_A: global.cursor_x = TextR.X; break;
+
+    // Move to end of line
+    case TB_KEY_CTRL_E:
+    {
+        if (global.cursor_x == TextR.X + TextR.W - 1) break;
+
+        if (TextPos + TextR.W > TextLen) 
+        {
+            // Put the cursor on the last character
+            global.cursor_x = TextR.X + (TextLen - TextOffset) % TextR.W;
+        }
+        else
+        {
+            global.cursor_x = TextR.X + TextR.W - 1;
+        }
+    } break;
+
+    // Move backwards
+    case TB_KEY_CTRL_B: 
+    case TB_KEY_ARROW_LEFT:
+    {
+        // Move forward by word
+        if (ev.mod == TB_MOD_CTRL)
+        {
+            u32 At = TextPos;
+            while(At && is_whitespace(Text[At])) At--;
+            while(At && !is_whitespace(Text[At])) At--;
+            while(TextPos - At++) TextBoxScrollLeft(TextR, &TextOffset);
+        }
+        // Move forward by character
+        else
+        {
+            if (TextPos == 0) break;
+            TextBoxScrollLeft(TextR, &TextOffset);
+        }
+    } break;
+
+    // Move forwards
+    case TB_KEY_CTRL_F:
+    case TB_KEY_ARROW_RIGHT:
+    {
+        // Move forward by word
+        if (ev.mod == TB_MOD_CTRL)
+        {
+            u32 At = TextPos;
+            while(At < TextLen && is_whitespace(Text[At])) At++;
+            while(At < TextLen && !is_whitespace(Text[At])) At++;
+            while(At-- - TextPos) TextBoxScrollRight(TextR, &TextOffset);
+        }
+        // Move forward by character
+        else
+        {
+            if (TextPos == TextLen) break;
+            TextBoxScrollRight(TextR, &TextOffset);
+        }
+    } break;
+
+    // Move up
+    case TB_KEY_CTRL_P:
+    case TB_KEY_ARROW_UP:
+    {
+        if (global.cursor_y == TextR.Y)
+        {
+            if (TextOffset == 0)
+            {
+                global.cursor_x = TextR.X;
+
+                break;
+            }
+
+            TextOffset -= TextR.W;
+            global.cursor_y = TextR.Y;
+        }
+        else
+        {
+            global.cursor_y--;
+        }
+    } break;
+
+    // Move down
+    case TB_KEY_CTRL_N:
+    case TB_KEY_ARROW_DOWN:
+    {
+        if (TextPos + TextR.W > TextLen) 
+        {
+            // Put the cursor on the last character
+            global.cursor_x = TextR.X + (TextLen - TextOffset) % (TextR.W);
+            global.cursor_y = TextR.Y + (TextLen - TextOffset) / TextR.W;
+
+            // If cursor ended 1 line under the bottom line this means that the text
+            // needs to be scrolled.
+            if (global.cursor_y == TextR.Y + TextR.H)
+            {
+                TextOffset += TextR.W;
+                global.cursor_y--;
+            }
+
+            break;
+        }
+
+        if (global.cursor_y == TextR.Y + TextR.H - 1)
+        {
+            TextOffset += TextR.W;
+        }
+        else
+        {
+            global.cursor_y++;
+        }
+    } break;
+    default:
+    {
+        Result = 0;
+    }
+    }
+
+    *TextLenPtr = TextLen;
+    *TextOffsetPtr = TextOffset;
+
+    return Result;
+}
+
+// Draws characters in Input in the TextR rectangle.
+// Skip printing TextOffset amount of characters.
+// InputLen is the amount of characters in Input.
+//
+// NOTE: TextR is always filled, when not enough characters in Input it will uses spaces instead.
+// This makes it easy to update the textbox by recalling this function.
+void
+TextBoxDraw(rect TextR, wchar_t *Text, u32 TextLen)
+{
+    // Draw the text right of the cursor
+    // NOTE: the cursor is assumed to be in the box
+    Assert(IsInRect(TextR, global.cursor_x, global.cursor_y));
+    s32 AtX = TextR.X, AtY = TextR.Y;
+    u32 At = 0;
+    while (AtY < TextR.Y + TextR.H)
+    {
+        if (At < TextLen) 
+        {
+            tb_printf(AtX++, AtY, 0, 0, "%lc", Text[At++]);
+        }
+        else
+        {
+            tb_printf(AtX++, AtY, 0, 0, " ");
+        }
+
+        if (AtX == TextR.X + TextR.W) { AtY++; AtX = TextR.X; }
+    }
+}
+
+// NOTE: To ensure that the text looks the same even when scrolling it you must provide the whole text,
+// wrap the whole text and the only show the portion that can fit in the Text Rectangle.
+
+// When line will exceed width break the word on the next line. This is done by looking backwards
+// for whitespace from TextR.W width. When a whitespace is found text is wrapped on the next line.
+void
+TextBoxDrawWrapped(rect TextR, wchar_t *Text, u32 TextLen)
+{
+    if (TextLen <= TextR.W)
+    {
+        tb_printf(TextR.X, TextR.Y, 0, 0, "%ls", Text);
+        tb_present();
+        global.cursor_x = TextR.X + TextLen;
+        global.cursor_y = TextR.Y;
+        return;
+    }
+
+    u32 SearchIndex = TextR.W; 
+    u32 PrevIndex = 0;
+    u32 Y = TextR.Y;
+
+    while (SearchIndex < TextLen)
+    {
+        while (Text[SearchIndex] != ' ')
+        {
+            SearchIndex--;
+            if (SearchIndex == PrevIndex)
+            {
+                SearchIndex += TextR.W;
+                break;
+            }
+        }
+
+        // Wrap
+        wchar_t BreakChar = Text[SearchIndex];
+        Text[SearchIndex] = 0;
+        tb_printf(TextR.X, Y, 0, 0, "%ls", Text + PrevIndex);
+        tb_present();
+        Text[SearchIndex] = BreakChar;
+
+        if (Y + 1 == TextR.Y + TextR.H)
+        {
+            global.cursor_y = Y;
+            global.cursor_x = TextR.X + (SearchIndex - PrevIndex);
+            return;
+        }
+        Y++;
+
+        if (BreakChar == L' ')
+        {
+            SearchIndex++;
+        }
+
+        PrevIndex = SearchIndex;
+        SearchIndex += TextR.W;
+    }
+
+    // This happens when SearchIndex exceeds TextLen but there is still some 
+    // text left to print.  We can assume that the text will fit because otherwise it would have
+    // been wrapped a second time and the loop would have returned.
+    tb_printf(TextR.X, Y, 0, 0, "%ls", Text + PrevIndex);
+    // NOTE: this sets the cursor position correctly
+
+    global.cursor_y = Y;
+    global.cursor_x = TextR.X + TextLen - PrevIndex;
+}
+
+#endif // BOX_H