m3te/tests/swipe_reshuffle.sx

// UI deadlock-recovery golden (final-review F1): prove the RENDERED swipe-commit
// path reshuffles a deadlocked board, just like the headless turn loop's no-moves
// rule (tests/level.sx). The iOS/macOS view commits a swipe through
// `plan_and_commit` (NOT `play_turn`), so the reshuffle must live on THAT shared
// path or a stuck board stays stuck on screen. This test drives exactly what
// BoardView.handle_event does — resolve a drag with `swipe_intent`, feed the intent
// into `plan_and_commit` — on the provably deadlocked diagonal-Latin-square board
// from tests/level.sx, asserting:
//   - BEFORE: no immediate match, zero legal swaps, status in_progress (stuck);
//   - AFTER the UI commit path resolves: the board RESHUFFLED — `has_legal_swap`
//     is true and >=1 legal swap exists, still with no immediate match — and the
//     reshuffle itself spent no move and no score (turn accounting unchanged).
// Pre-fix `plan_and_commit` skipped the reshuffle, so `has_legal_swap` stayed false
// after and this FAILS; with the shared `reshuffle_if_deadlocked` wired in it PASSES.
// No rendering, no model reach-around. Links headless like tests/anim_plan.sx;
// avoids tests/test.sx (its trace.sx pulls in a second `Frame` that collides with
// the UI one). Failure is a non-zero exit code (the runner checks exit + stdout).
#import "modules/std.sx";
#import "modules/ui/types.sx";
#import "board.sx";
#import "board_anim.sx";
#import "board_layout.sx";
#import "swipe.sx";

SEED :: 1337;

// Inverse of `gem_char`: map a board character back to its Gem so the deadlocked
// board can be written as a human-readable grid (mirrors tests/level.sx).
char_to_gem :: (c: u8) -> Gem {
    if c == EMPTY_CHAR { return .empty; }
    for 0..GEM_COUNT (i) {
        if GEM_CHARS[i] == c { return cast(Gem) i; }
    }
    .red
}

// Load an 8x8 board from `rows` (top row first), seeded RNG, score zeroed, turn
// counters reset to a fresh game, and the per-level goal set.
load_board :: (rows: []string, seed: i64, move_limit: i64, target_score: i64) -> Board {
    b : Board = ---;
    for 0..BOARD_ROWS (row) {
        line := rows[row];
        for 0..BOARD_COLS (col) {
            b.set(col, row, char_to_gem(line[col]));
        }
    }
    b.rng = rng_seeded(seed);
    b.score = 0;
    b.moves_made = 0;
    b.move_limit = move_limit;
    b.target_score = target_score;
    b
}

cell_center :: (lay: *BoardLayout, col: i64, row: i64) -> Point {
    cf := lay.cell_frame(col, row);
    Point.{ x = cf.mid_x(), y = cf.mid_y() }
}

main :: () -> i32 {
    fails : i64 = 0;

    // 800×600, no safe inset → 600px square grid, cell 75, origin (100, 0). A 60px
    // drag clears the cell*0.5 = 37.5px swipe threshold on the dominant axis — the
    // SAME layout/threshold tests/swipe_commit.sx drives the UI path through.
    lay : BoardLayout = ---;
    lay.compute(Frame.make(0.0, 0.0, 800.0, 600.0), EdgeInsets.zero());
    D : f32 = 60.0;

    // The provably deadlocked board from tests/level.sx: gem(col,row)=(col-row) mod
    // 6, a diagonal Latin square. Equal gems lie only on slope-1 diagonals, so no
    // row/column holds two of a kind within reach — no immediate match and no
    // orthogonal swap can line up three.
    print("== deadlocked board: UI swipe-commit path must reshuffle ==\n");
    b := load_board(.[
        "ROYGBPRO",
        "PROYGBPR",
        "BPROYGBP",
        "GBPROYGB",
        "YGBPROYG",
        "OYGBPROY",
        "ROYGBPRO",
        "PROYGBPR",
    ], SEED, 10, 1500);
    out(board_dump(@b));

    pre_m  := find_matches(@b);
    pre_sw := legal_swaps(@b);
    print("before: matches {} legal_swaps {} has_legal_swap {} status {}\n",
          pre_m.count(), pre_sw.len, has_legal_swap(@b), status_name(level_status(@b)));
    if pre_m.count() != 0 { fails += 1; }
    if pre_sw.len != 0 { fails += 1; }
    if has_legal_swap(@b) { fails += 1; }
    if level_status(@b) != .in_progress { fails += 1; }

    score_before := b.score;
    made_before  := b.moves_made;
    remain_before := b.moves_remaining();

    // Drive the EXACT UI path: a rightward drag on (0,0) resolves to the (0,0)->(1,0)
    // swap intent, which BoardView.handle_event feeds straight into plan_and_commit.
    // On this deadlocked board every swap is illegal (no match), so the swipe itself
    // commits nothing — the recovery must come from the post-settle reshuffle.
    a0 := cell_center(@lay, 0, 0);
    if s := swipe_intent(@lay, a0, Point.{ x = a0.x + D, y = a0.y }) {
        print("intent ({},{})->({},{})\n", s.a.col, s.a.row, s.b.col, s.b.row);
        if !(s.a.col == 0 and s.a.row == 0 and s.b.col == 1 and s.b.row == 0) { fails += 1; }
        mv := plan_and_commit(@b, s.a, s.b);
        print("commit: legal {} rounds {} awarded {}\n", mv.legal, mv.rounds.len, mv.awarded);
        // The illegal swipe spends nothing; its timeline is the bare ping-back.
        if mv.legal { fails += 1; }
        if mv.rounds.len != 0 { fails += 1; }
    } else {
        print("intent none\n");
        fails += 1;
    }

    post_m  := find_matches(@b);
    post_sw := legal_swaps(@b);
    print("after: matches {} legal_swaps {} has_legal_swap {} status {}\n",
          post_m.count(), post_sw.len, has_legal_swap(@b), status_name(level_status(@b)));
    print("after: score {} moves_made {} moves_remaining {}\n",
          b.score, b.moves_made, b.moves_remaining());
    out(board_dump(@b));

    // The fix: the UI commit path reshuffled the deadlock away. has_legal_swap flips
    // false -> true; >=1 legal swap exists; still no immediate match.
    if !has_legal_swap(@b) { fails += 1; }
    if post_sw.len <= 0 { fails += 1; }
    if post_m.count() != 0 { fails += 1; }

    // The reshuffle is NOT a move: score, moves spent, and budget are untouched.
    if b.score != score_before { fails += 1; }
    if b.moves_made != made_before { fails += 1; }
    if b.moves_remaining() != remain_before { fails += 1; }
    if level_status(@b) != .in_progress { fails += 1; }

    if fails == 0 {
        print("ok: UI swipe-commit path reshuffles a deadlocked board\n");
        return 0;
    }
    print("FAIL: {} UI-reshuffle checks failed\n", fails);
    return 1;
}