started implementation of powers. I don't know how to unstage things …

…so im just going to push it.

chess.nimble

@@ -22,7 +22,7 @@ task html, "compiles html in main.nim":
     exec "mv app.js app"
 
 task jsc, "compiles just the js, instead of doing all that rewriting":
-    exec "nim js --out:app/app.js src/main.nim"
+    exec "nim js --out:app.js src/main.nim"
 
 task host, "hosts app.html, build from main.nim with task html":
     exec "npx parcel app/app.html"

src/power.nim

@@ -0,0 +1,71 @@
+import piece, moves
+from std/sequtils import foldr, mapIt, filterIt
+from std/random import randomize, rand
+
+randomize()
+
+type
+    Tier* = enum
+        Common, Uncommon, Rare, UltraRare
+    FilePath* = string
+
+    Power* = object
+        name*: string
+        synergy*: bool = true
+        tier*: Tier
+        rarity*: int = 8
+        description*: string
+        icon*: FilePath = ""
+        onStart*: proc (side: Color, b: var ChessBoard)
+
+    Synergy* = tuple
+        power: Power
+        requirements: seq[string]
+        replacement: string = ""
+
+var 
+    powers: seq[Power]
+    synergies: seq[Synergy]
+    commonPowers: seq[Power]
+    uncommonPowers: seq[Power]
+    rarePowers: seq[Power]
+    ultraRarePowers: seq[Power]
+
+
+proc hasIcon*(p: Power): bool = 
+    return p.icon != ""
+
+proc registerSynergy*(s: Synergy) = 
+    synergies.add(s)
+
+proc synergize(pool: seq[Power], currentPowers: seq[Power] ): seq[Power] = 
+    for s in synergies:
+        if currentPowers.filterIt(it.name in s.requirements).len == s.requirements.len:
+            if s.replacement == "":
+                return pool & s.power
+            else: 
+                return pool.filterIt(it.name != s.replacement) & s.power
+
+
+proc registerPower*(p: Power) = 
+    powers.add(p)
+    case p.tier
+    of Common: commonPowers.add(p)
+    of Uncommon: uncommonPowers.add(p)
+    of Rare: rarePowers.add(p)
+    of UltraRare: ultraRarePowers.add(p)
+
+proc randomPower*(t: Tier, currentPowers: seq[Power]): Power = 
+    let search = case t 
+        of Common: commonPowers.synergize(currentPowers)
+        of Uncommon: uncommonPowers.synergize(currentPowers)
+        of Rare: rarePowers.synergize(currentPowers)
+        of UltraRare: ultraRarePowers.synergize(currentPowers)
+
+    let sum = foldr(search.mapIt(it.rarity), a + b)
+    var x: int = rand(sum)
+
+    for p in search:
+        x -= p.rarity
+        if x <= 0: return p
+

src/powers.nim

@@ -0,0 +1,286 @@
+import power, moves, piece, board, basePieces
+
+const empress*: Power = Power(
+    name: "empress",
+    tier: Uncommon,
+    description: "Your queen ascends, gaining the movement of a standard knight. ",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) =
+            let rank = if side == black: 0 else: 7
+            b[rank][3].moves.add(knightMoves)
+            b[rank][3].takes.add(knightTakes)
+)
+
+const diagnalMoves*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfFree(board, p.tile, shooterFactory(1,1))
+    discard result.addIfFree(board, p.tile, shooterFactory(-1,1))
+    discard result.addIfFree(board, p.tile, shooterFactory(1,-1))
+    discard result.addIfFree(board, p.tile, shooterFactory(-1,-1))
+
+const diagnalTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfTake(board, p, p.tile, shooterFactory(1,1))
+    discard result.addIfTake(board, p, p.tile, shooterFactory(-1,1))
+    discard result.addIfTake(board, p, p.tile, shooterFactory(1,-1))
+    discard result.addIfTake(board, p, p.tile, shooterFactory(-1,-1))
+
+const leftRightMoves*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfFree(board, p.tile, tileLeft)
+    discard result.addIfFree(board, p.tile, tileRight)
+
+const leftRightTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfTake(board, p, p.tile, tileLeft)
+    discard result.addIfTake(board, p, p.tile, tileRight)
+
+const whiteForwardMoves*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfFree(board, p.tile, tileAbove)
+
+const blackForwardMoves*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfFree(board, p.tile, tileBelow)
+
+const whiteForwardTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfTake(board, p, p.tile, tileAbove)
+
+const blackForwardTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    discard result.addIfTake(board, p, p.tile, tileBelow)
+
+proc silverGeneralPromote(taker: Tile, taken: Tile, board: var ChessBoard) = 
+    if (taken.rank == 0 or taken.rank == 7) and not board[taken.rank][taken.file].promoted: 
+        board[taken.rank][taken.file].moves &= leftRightMoves
+        board[taken.rank][taken.file].moves &= leftRightTakes
+
+const mysteriousSwordsmanLeft*: Power = Power(
+    name: "Mysterious Swordsman", 
+    tier: Common, 
+    rarity: 4, 
+    description: 
+        """A mysterious swordsman joins your rank. 
+        Your second pawn from the left is replaced with a silver general from Shogi.""",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) = 
+            if side == black: 
+                b[1][1].moves &= [diagnalMoves, blackForwardMoves]
+                b[1][1].takes &= [diagnalTakes, blackForwardTakes]
+                b[1][1].onEndTurn = silverGeneralPromote
+            else: 
+                b[6][1].moves &= [diagnalMoves,  whiteForwardMoves]
+                b[6][1].takes &= [diagnalTakes,  whiteForwardTakes]
+                b[6][1].onEndTurn = silverGeneralPromote
+)
+
+const mysteriousSwordsmanRight*: Power = Power(
+    name: "Mysterious Swordsman", 
+    tier: Common, 
+    rarity: 4,
+    description: 
+        """A mysterious swordsman joins your rank. 
+        Your second pawn from the right is replaced with a silver general from Shogi.""",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) = 
+            if side == black: 
+                b[1][6].moves &= [diagnalMoves, blackForwardMoves]
+                b[1][6].takes &= [diagnalTakes, blackForwardTakes]
+                b[1][6].onEndTurn = silverGeneralPromote
+                b[1][6].item = fairy
+            else: 
+                b[6][6].moves &= [diagnalMoves,  whiteForwardMoves]
+                b[6][6].takes &= [diagnalTakes,  whiteForwardTakes]
+                b[6][6].onEndTurn = silverGeneralPromote
+                b[6][6].item = fairy
+)
+
+const developed*: Power = Power(
+    name: "Developed",
+    tier: Common,
+    description: 
+        """Your board arrives a little developed. Your 2 center pawns start one tile forward. 
+        They can still move up 2 for their first move.""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            if side == black:
+                b[2][3] = b[1][3]
+                b[2][4] = b[1][4]
+                b[1][3] = air
+                b[1][4] = air
+            else:
+                b[5][3] = b[6][3]
+                b[5][4] = b[6][4]
+                b[6][3] = air
+                b[6][4] = air                
+)
+
+const cannibalRookTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    result.add(lineTakes(board, p, tileAbove, cannibalismFlag = true))
+    result.add(lineTakes(board, p, tileBelow, cannibalismFlag = true))
+    result.add(lineTakes(board, p, tileLeft, cannibalismFlag = true))
+    result.add(lineTakes(board, p, tileRight, cannibalismFlag = true))
+
+const cannibalBishopTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves =
+    result.add(lineTakes(board, p, shooterFactory(1, 1), cannibalismFlag = true))
+    result.add(lineTakes(board, p, shooterFactory(-1, 1), cannibalismFlag = true))
+    result.add(lineTakes(board, p, shooterFactory(1, -1), cannibalismFlag = true))
+    result.add(lineTakes(board, p, shooterFactory(-1, -1), cannibalismFlag = true))
+
+const cannibalKingTakes*: MoveProc = func (board: ChessBoard, p: Piece): Moves = 
+    for i in -1..1:
+        for j in -1..1:
+            discard result.addIfTake(board, p, p.tile, shooterFactory(i,j), cannibalismFlag = true)
+
+const stepOnMe*: Power = Power(
+    name: "Step on me",
+    tier: Common,
+    description:
+        """Your Queen can take your own pieces. It's literally useless, but if that's your thing...""",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) = 
+            for i in 0..b.len:
+                for j in 0.. b[0].len:
+                    if b[i][j].item == queen and b[i][j].isColor(side):
+                        b[i][j].moves = @[cannibalBishopTakes, cannibalKingTakes, cannibalRookTakes]
+)
+
+const illegalFormationRL*: Power = Power(
+    name: "Illegal Formation", 
+    tier: Common, 
+    rarity: 2,
+    description: 
+        """ILLEGAL FORMATION: YOUR PAWN ABOVE YOUR LEFT ROOK SWAPS PLACES WITH YOUR LEFT ROOK""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            let rank = if side == black: 0 else: 6
+            let temp = b[rank][0] 
+            b[rank][0] = b[rank + 1][0]
+            b[rank + 1][0] = temp
+)
+
+const illegalFormationRR*: Power = Power(
+    name: "Illegal Formation", 
+    tier: Common, 
+    rarity: 2,
+    description: 
+        """ILLEGAL FORMATION: YOUR PAWN ABOVE YOUR RIGHT ROOK SWAPS PLACES WITH YOUR RIGHT ROOK""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            let rank = if side == black: 0 else: 6
+            let temp = b[rank][7] 
+            b[rank][7] = b[rank + 1][7]
+            b[rank + 1][7] = temp
+)
+
+const illegalFormationBL*: Power = Power(
+    name: "Illegal Formation", 
+    tier: Common, 
+    rarity: 2,
+    description: 
+        """ILLEGAL FORMATION: YOUR PAWN ABOVE YOUR LEFT BISHOP SWAPS PLACES WITH YOUR LEFT BISHOP""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            let rank = if side == black: 0 else: 6
+            let temp = b[rank][2] 
+            b[rank][2] = b[rank + 1][2]
+            b[rank + 1][2] = temp
+)
+
+const illegalFormationBR*: Power = Power(
+    name: "Illegal Formation", 
+    tier: Common, 
+    rarity: 2,
+    description: 
+        """ILLEGAL FORMATION: YOUR PAWN ABOVE YOUR RIGHT BISHOP SWAPS PLACES WITH YOUR RIGHT BISHOP""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            let rank = if side == black: 0 else: 6
+            let temp = b[rank][5] 
+            b[rank][5] = b[rank + 1][5]
+            b[rank + 1][5] = temp
+)
+
+proc putInTheWorkPromotion(taker: Tile, taken: Tile, board: var ChessBoard) =
+    onPawnEnd(taker, taken, board)
+    let pawn = board[taken.rank][taken.file]
+    if pawn.piecesTaken == 3:
+        if pawn.color == black and not pawn.promoted:
+            board[taken.rank][taken.file] = whiteQueen.pieceCopy(piecesTaken=pawn.piecesTaken, tile=pawn.tile, promoted = true)
+        elif pawn.color == white and not pawn.promoted:
+            board[taken.rank][taken.file] = blackQueen.pieceCopy(piecesTaken=pawn.piecesTaken, tile=pawn.tile, promoted = true)
+
+#...
+#Just don't look at it and it's not that bad
+const putInTheWork*: Power = Power(
+    name: "Put in the work!", 
+    tier: Common,
+    description:
+        """Get to work son. If any of your pawns takes 3 pieces, it automatically promotes""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            for i in 0..b.len:
+                for j in 0..b[0].len:
+                    if b[i][j].item == pawn and b[i][j].isColor(side):
+                        b[i][j].onEndTurn = putInTheWorkPromotion
+
+)
+
+const wanderingRoninLeft*: Power = Power(
+    name: "Wandering Ronin", 
+    tier: Uncommon, 
+    rarity: 4, 
+    description: 
+        """A wandering Ronin joins your rank. 
+        Your third pawn from the left is replaced with a gold general from Shogi.""",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) =
+            let rank = if side == black: 1 else: 6
+            b[rank][2].moves &= [diagnalMoves, blackForwardMoves, leftRightMoves]
+            b[rank][2].takes &= [diagnalTakes, blackForwardTakes, leftRightTakes]
+            b[rank][2].onEndTurn = defaultOnEndTurn #Gold generals do not promote
+            b[rank][2].item = fairy
+)
+
+const wanderingRoninRight*: Power = Power(
+    name: "Wandering Ronin", 
+    tier: Uncommon, 
+    rarity: 4, 
+    description: 
+        """A wandering Ronin joins your rank. 
+        Your third pawn from the right is replaced with a gold general from Shogi.""",
+    onStart: 
+        proc (side: Color, b: var ChessBoard) = 
+            let rank = if side == black: 1 else: 6
+            b[rank][5].moves &= [diagnalMoves, blackForwardMoves, leftRightMoves]
+            b[rank][5].takes &= [diagnalTakes, blackForwardTakes, leftRightTakes]
+            b[rank][5].onEndTurn = defaultOnEndTurn #Gold generals do not promote
+            b[rank][5].item = fairy
+)
+
+const warewolves*: Power = Power(
+    name: "Warewolves",
+    tier: Uncommon,
+    description: 
+        """Your leftmost and rightmost pawns are secretly warewolves! When they take a piece, they eat it and gain the ability to jump like a knight. They do not promote.""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            let update = proc (taker: Tile, taken: Tile, board: var ChessBoard) = 
+                if board[taken.rank][taken.file].piecesTaken == 1 and not board[taken.rank][taken.file].promoted:
+                    board[taken.rank][taken.file].moves &= knightMoves
+                    board[taken.rank][taken.file].takes &= knightTakes
+
+            let rank = if side == black: 1 else: 6
+            b[rank][0].onEndTurn = update
+            b[rank][0].item = fairy
+            b[rank][7].onEndTurn = update
+            b[rank][7].item = fairy
+
+)
+
+const archBishops*: Power = Power(
+    name: "Archbishops",
+    tier: Uncommon,
+    description:
+        """Your bishops ascend to archbishops, gaining the movement of a knight.""",
+    onStart:
+        proc (side: Color, b: var ChessBoard) = 
+            for i in 0..b.len:
+                for j in 0..b[0].len:
+                    if b[i][j].item == bishop and b[i][j].isColor(side):
+                        b[i][j].moves &= knightMoves   
+                        b[i][j].takes &= knightTakes        
+)