Retro Minesweeper game

Gameplay Instructions

1. Game Objective:
Win by revealing all the non-mine squares on the board.
Stepping on any mine → Instant loss.

2. Three Difficulty Levels:
Beginner: 9 × 9
Intermediate: 16 × 16
Expert: 20 × 20

3. Head HUD:
Left Red Number (Mine Counter): Displays "Remaining Mines = Total Mines - Number of Flags Planted".
Planting a flag decrements the number, retrieving a flag increases it.

Middle Smiley Face (Reset Button): Clicking this at any time will restart the game on the same difficulty.
The emoticon changes automatically depending on the game status:

😊 In Progress
😞 Lost after stepping on a mine
😎 Won (Sunglasses Face)

Right Red Number (Timer): Starts counting down from the first time a square is revealed, up to a maximum of 999 seconds.

4. Three Mode Buttons (Core: Simulates a Windows Mouse)

Android lacks a right-click; use three buttons to switch "what to do next time you click a square."
Only one button can be active at a time.

◀ Left Arrow: Reveal a Square (equivalent to the Windows left click):
a. Click any unrevealed gray square.
b. Second click ensures safety - the program will wait until you click the first time before placing mines on
"squares other than the one you clicked and not adjacent to," so instant death at the start is impossible.
c. Three possible outcomes after revealing: Numbers 1-8: The number of mines in the 8 neighboring squares.
- Blank Square (0 adjacent mines): The program automatically flood-fills and
reveals all connected zero-adjacent mine squares and their boundary numbered squares.
- Mine *: Red background, game over. All remaining mines will be revealed,
and mismarked flags will turn into red Xs.
▶ Right Arrow: Mark/Question Mark/Cancel (equivalent to Windows right-click):
Clicking on a "not yet revealed" square will cycle through the status: Blank → F (Flag, red)
→ ? (Question Mark, black) → Blank → ...
- F (Flag): You've identified this as a mine. It uses 1 "Flag-Planted" quota, and the mine counter decreases by 1.
- ? (Question Mark): Uncertain. It has no effect itself, just a reminder.
- Clicking on revealed numbered squares in R mode has no effect.

Tactical Reminder: The flag itself doesn't verify correctness; the system simply trusts you.
Incorrectly marked flags are fatal in ◀▶ Double Arrow mode (see next section).

◀▶ Double Arrow: Quickly Expand (equivalent to pressing the left and right arrow keys simultaneously in Windows)
An advanced operation familiar to Windows players. On Android, this originally required pressing the left
and right arrow keys simultaneously; here it's simplified to "switch to ◀▶ Double Arrow mode → tap once".

Activation conditions (all three must be met, otherwise clicking will have no effect):
a. The selected square must be already revealed.
b. The number in the selected square must be ≥ 1.
c. The number of flags in the surrounding 8 squares equals the number in the selected square.
d. When activated:
- Automatically reveals all unflagged squares in the surrounding 8 squares (including those marked with question marks).
- ⚠️ If a flag is marked incorrectly (it's not actually a mine, but you've marked it; or you missed marking a mine),
the Chord will directly reveal the "real mine that should have been marked but wasn't"
→ immediately triggering a mine and losing.
- If the surrounding squares have 0 adjacent mines, it will also trigger a flood-fill chain reaction.
e. Use: When you have marked all the mines around a numbered square, use the ◀▶ double arrows to expand other safe squares,
much faster than clicking one by one. But you need to be confident in your flag markings.