; ==============================================================================
; EBLAN ENGINE - 2D Canvas Overlay, Font 8x8 Text & Minimap Radar
; ==============================================================================

.code

; ------------------------------------------------------------------------------
; DrawPixel: Draws a single 32-bit pixel with bounds checking
; ------------------------------------------------------------------------------
DrawPixel PROC x:DWORD, y:DWORD, color:DWORD
    mov eax, x
    cmp eax, 0
    jl @F
    cmp eax, SCREEN_W
    jge @F

    mov edx, y
    cmp edx, 0
    jl @F
    cmp edx, SCREEN_H
    jge @F

    imul edx, SCREEN_PITCH
    shl eax, 2
    add eax, edx
    add eax, OFFSET screenBuffer
    mov ecx, color
    mov [eax], ecx
@@:
    ret
DrawPixel ENDP

; ------------------------------------------------------------------------------
; DrawRect: Draws a filled rectangle
; ------------------------------------------------------------------------------
DrawRect PROC uses ebx ecx edx edi, x:DWORD, y:DWORD, w:DWORD, h:DWORD, color:DWORD
    LOCAL curY:DWORD, endY:DWORD
    LOCAL curX:DWORD, endX:DWORD

    mov eax, x
    mov curX, eax
    add eax, w
    mov endX, eax

    mov eax, y
    mov curY, eax
    add eax, h
    mov endY, eax

loop_rect_y:
    mov eax, curY
    cmp eax, endY
    jge rect_done
    cmp eax, 0
    jl next_rect_y
    cmp eax, SCREEN_H
    jge rect_done

    mov ebx, curX
loop_rect_x:
    cmp ebx, endX
    jge next_rect_y
    cmp ebx, 0
    jl next_rect_x
    cmp ebx, SCREEN_W
    jge next_rect_y

    ; Pixel address
    mov eax, curY
    imul eax, SCREEN_PITCH
    mov edx, ebx
    shl edx, 2
    add eax, edx
    add eax, OFFSET screenBuffer
    mov edx, color
    mov [eax], edx

next_rect_x:
    inc ebx
    jmp loop_rect_x

next_rect_y:
    inc curY
    jmp loop_rect_y

rect_done:
    ret
DrawRect ENDP

; ------------------------------------------------------------------------------
; DrawRectOutline: Draws a 1-pixel rectangle outline
; ------------------------------------------------------------------------------
DrawRectOutline PROC x:DWORD, y:DWORD, w:DWORD, h:DWORD, color:DWORD
    LOCAL x2:DWORD, y2:DWORD

    mov eax, x
    add eax, w
    dec eax
    mov x2, eax

    mov eax, y
    add eax, h
    dec eax
    mov y2, eax

    ; Top & Bottom horizontal lines
    mov ecx, x
@@:
    cmp ecx, x2
    jg @F
    invoke DrawPixel, ecx, y, color
    invoke DrawPixel, ecx, y2, color
    inc ecx
    jmp @B
@@:

    ; Left & Right vertical lines
    mov edx, y
@@:
    cmp edx, y2
    jg @F
    invoke DrawPixel, x, edx, color
    invoke DrawPixel, x2, edx, color
    inc edx
    jmp @B
@@:
    ret
DrawRectOutline ENDP

; ------------------------------------------------------------------------------
; DrawChar8x8: Renders an 8x8 ASCII character with transparent background
; ------------------------------------------------------------------------------
DrawChar8x8 PROC uses ebx ecx edx esi edi, posX:DWORD, posY:DWORD, charCode:DWORD, color:DWORD
    LOCAL row:DWORD, col:DWORD
    LOCAL fontPtr:DWORD

    ; Find glyph offset: charCode * 8 (full 256-glyph CP1251 font)
    mov eax, charCode
    and eax, 0FFh
    shl eax, 3                  ; * 8 bytes
    add eax, OFFSET font8x8
    mov fontPtr, eax

    mov row, 0
loop_char_row:
    mov eax, fontPtr
    add eax, row
    movzx ebx, byte ptr [eax]    ; 8-bit glyph row mask

    mov col, 0
loop_char_col:
    test ebx, 80h               ; Check MSB
    jz next_char_col

    ; Draw text pixel with black drop-shadow for high contrast!
    mov eax, posX
    add eax, col
    inc eax
    mov edx, posY
    add edx, row
    inc edx
    invoke DrawPixel, eax, edx, 00000000h

    mov eax, posX
    add eax, col
    mov edx, posY
    add edx, row
    invoke DrawPixel, eax, edx, color

next_char_col:
    shl ebx, 1
    inc col
    cmp col, 8
    jl loop_char_col

    inc row
    cmp row, 8
    jl loop_char_row

    ret
DrawChar8x8 ENDP

; ------------------------------------------------------------------------------
; DrawString8x8: Renders a null-terminated string
; ------------------------------------------------------------------------------
DrawString8x8 PROC uses ebx esi, posX:DWORD, posY:DWORD, pText:DWORD, color:DWORD
    mov esi, pText
    mov ebx, posX

loop_chars:
    movzx eax, byte ptr [esi]
    test al, al
    jz str_done

    invoke DrawChar8x8, ebx, posY, eax, color
    add ebx, 8
    inc esi
    jmp loop_chars

str_done:
    ret
DrawString8x8 ENDP

; ------------------------------------------------------------------------------
; DrawNumber8x8: Formats and prints an unsigned integer
; ------------------------------------------------------------------------------
DrawNumber8x8 PROC uses ebx ecx edx, posX:DWORD, posY:DWORD, value:DWORD, color:DWORD
    LOCAL numBuf[16]:BYTE

    lea ebx, [numBuf + 15]
    mov byte ptr [ebx], 0       ; null terminator
    mov eax, value

format_num_loop:
    xor edx, edx
    mov ecx, 10
    div ecx
    add dl, '0'
    dec ebx
    mov [ebx], dl
    test eax, eax
    jnz format_num_loop

    invoke DrawString8x8, posX, posY, ebx, color
    ret
DrawNumber8x8 ENDP

; ------------------------------------------------------------------------------
; DrawMinimap: Renders top-down 2D radar overlay with player & viewing cone
; ------------------------------------------------------------------------------
DrawMinimap PROC uses ebx ecx edx esi edi
    LOCAL mapStartX:DWORD, mapStartY:DWORD
    LOCAL cellSize:DWORD
    LOCAL mx:DWORD, my:DWORD
    LOCAL pxScreen:DWORD, pyScreen:DWORD

    cmp keyShowMap, 0
    je minimap_done

    mov mapStartX, 250          ; Top-right corner
    mov mapStartY, 10
    mov cellSize, 2             ; 2x2 pixels per cell (64x64 pixel radar)

    ; Background & Border
    invoke DrawRect, mapStartX, mapStartY, 66, 66, 00101010h
    invoke DrawRectOutline, mapStartX, mapStartY, 66, 66, 00FFD000h

    ; Draw Grid Cells
    mov my, 0
loop_mm_y:
    mov mx, 0
loop_mm_x:
    invoke GetMapCell, mx, my
    test eax, eax
    jz next_mm_x

    ; Solid wall cell color
    mov edx, 00808080h          ; Gray
    cmp eax, CELL_DOOR
    jne @F
    mov edx, 00E0A000h          ; Orange door
@@:
    cmp eax, CELL_DOOR_OPEN
    jne @F
    mov edx, 0000FF00h          ; Green open door
@@:
    mov eax, mx
    shl eax, 1                  ; mx * 2
    add eax, mapStartX
    inc eax

    mov ecx, my
    shl ecx, 1                  ; my * 2
    add ecx, mapStartY
    inc ecx

    invoke DrawRect, eax, ecx, 2, 2, edx

next_mm_x:
    inc mx
    cmp mx, MAP_W
    jl loop_mm_x

    inc my
    cmp my, MAP_H
    jl loop_mm_y

    ; Draw Player Position (Yellow dot)
    mov eax, playerX
    sar eax, 5                  ; playerX / 32
    add eax, mapStartX
    inc eax
    mov pxScreen, eax

    mov eax, playerY
    sar eax, 5                  ; playerY / 32
    add eax, mapStartY
    inc eax
    mov pyScreen, eax

    invoke DrawRect, pxScreen, pyScreen, 2, 2, 00FFFF00h

    ; Draw Direction Cone Pointer
    mov eax, playerAngle
    and eax, ANGLE_MASK
    mov ebx, [tableCos + eax*4]
    imul ebx, 6
    sar ebx, 16
    add ebx, pxScreen

    mov ecx, [tableSin + eax*4]
    imul ecx, 6
    sar ecx, 16
    add ecx, pyScreen

    invoke DrawPixel, ebx, ecx, 00FF0000h ; Red direction tip

minimap_done:
    ret
DrawMinimap ENDP