// Space Taxi -- HUD (score / lives / level / current-fare strip).
//
// Lives in the bottom 3 tile-rows (y = 176..199) below the playfield.
// Renders textual score / lives / level name / current fare via the
// font asset (loaded by stRender). No fuel meter: the C64 original
// has no fuel mechanic. The strip at $DBA2-$DBCB in the original game
// is a per-frame Y-velocity status indicator ($6419), not a fuel bar.

#include <stdio.h>
#include <string.h>

#include "spacetaxi.h"

JOEYLIB_SEGMENT("STAXI")


void stHudDraw(jlSurfaceT *stage, const StGameT *game) {
    char     buf[32];
    char     livesBuf[ST_MAX_PADS + 1];
    uint8_t  i;

    // Wipe the HUD band with the level's border color (C64 $7D00 -> $D020).
    // Most canonical levels set both border and bg to 0 (black), so this
    // looks identical to the previous hardcoded ST_HUD_BG_COLOR for them.
    jlFillRect(stage,
               0,
               (int16_t)(ST_HUD_ROW * ST_TILE_PIXELS),
               SURFACE_WIDTH,
               (int16_t)(ST_HUD_ROW_COUNT * ST_TILE_PIXELS),
               game->level.borderColor);

    // 4-digit score with a separator after the thousands digit, matching
    // the C64 HUD template at $43B1 ('___ . __'). The format puts the
    // ones digit at position 3 and uses '.' as a thousands marker. Range
    // is 0..9999; beyond that we wrap (the C64 BCD can't exceed 9999
    // either).
    snprintf(buf, sizeof(buf), "%04lu.",
             (unsigned long)(game->score % 10000ul));
    stRenderDrawText(stage, 0u, (uint8_t)ST_HUD_ROW, buf);

    // Lives indicator: graphic-ish "cabs remaining" -- one 'O' per life,
    // up to 9. C64 shows this as filled glyphs in color RAM ($DBDC etc).
    for (i = 0u; i < 9u && i < game->lives; i++) {
        livesBuf[i] = 'O';
    }
    livesBuf[i] = '\0';
    stRenderDrawText(stage, 7u, (uint8_t)ST_HUD_ROW, livesBuf);

    // Level name right-aligned in the 40-col HUD row.
    {
        uint8_t nameLen = (uint8_t)strlen(game->level.name);
        uint8_t col     = (nameLen < ST_TILEMAP_W)
                        ? (uint8_t)(ST_TILEMAP_W - nameLen)
                        : 0u;
        stRenderDrawText(stage, col, (uint8_t)ST_HUD_ROW, game->level.name);
    }

    // Active fare display: where the current passenger wants to go
    // (or "PAD x WANTS y" when one is still waiting to be picked up).
    for (i = 0u; i < ST_MAX_PASSENGERS; i++) {
        const StPassengerT *p = &game->passengers[i];
        if (p->active && p->onboard &&
            p->destPad < game->level.padCount) {
            char dest = (char)game->level.pads[p->destPad].letter;
            snprintf(buf, sizeof(buf), "FARE %c", dest);
            stRenderDrawText(stage, 0u, (uint8_t)(ST_HUD_ROW + 1u), buf);
            break;
        }
        if (p->active && !p->onboard &&
            p->currentPad < game->level.padCount) {
            char src  = (char)game->level.pads[p->currentPad].letter;
            char dest = (p->destPad < game->level.padCount)
                      ? (char)game->level.pads[p->destPad].letter : '?';
            snprintf(buf, sizeof(buf), "PAD %c WANTS %c", src, dest);
            stRenderDrawText(stage, 0u, (uint8_t)(ST_HUD_ROW + 1u), buf);
            break;
        }
    }
}