; Copyright (C) 2018 Christophe Meneboeuf <christophe@xtof.info>
;
; This program is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, either version 3 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program. If not, see <http://www.gnu.org/licenses/>.


.include "world.inc"
.include "tiles.inc"
.include "random.inc"
.include "math.inc"
.include "memory.inc"



.export World

; initializes the world
; DESTROYS A,X,Y, ZERO_2_1, ZERO_2_2, ZERO_2_3
.export world_init

; sets the player's position onto the Maze
; in: X = x coord in the maze
; in: Y = y coord in the maze
; out : X and Y as they where given
; DESTROYS A,X,Y, ZERO_2_1, ZERO_2_2, ZERO_2_4, ZERO_2_5
.export world_set_player

; Computes the adress corresponding to the coordinates in the maze
; in: X = x coord in the maze
; in: Y = y coord in the maze
; out: AX = Address corresponding to (x,y) in the World array
; DESTROYS A,X,Y, ZERO_2_1, ZERO_2_2, ZERO_2_3
.export Compute_Maze_Addr


.define TILE_NR     ZERO_2_1
.define COORD_X     ZERO_2_1
.define COORD_Y     ZERO_2_2
.define OFFSET      ZERO_2_2


.BSS

; The tile where the player stands
.struct Tile_player_standing
    addr     .word   ; adress of the location 
    actor     .byte  ; actor on the location tile
.endstruct

.CODE

; @param X Player's x
; @param Y Player's y
world_init:
    ; Saving the first tile on which the player stands
    ; FIXME player could be standing anywhere on any type of floor
    jsr Compute_Maze_Addr
    stx Tile_player_standing::addr
    sta Tile_player_standing::addr+1
    stx ZERO_2_1
    sta ZERO_2_1+1
    ldy #0
    lda (ZERO_2_1), Y
    sta Tile_player_standing::actor

    rts


; sets the player's position onto the World
world_set_player:

    stx ZERO_2_4
    sty ZERO_2_5

    ; restore the previous tile
    ldx Tile_player_standing::addr
    lda Tile_player_standing::addr+1
    stx ZERO_2_1
    sta ZERO_2_1+1
    ldy #0
    lda Tile_player_standing::actor
    sta (ZERO_2_1), Y

    ; save the next tile
    ldx ZERO_2_4
    ldy ZERO_2_5
    jsr Compute_Maze_Addr   ; get's player's position address in memory
    stx Tile_player_standing::addr
    sta Tile_player_standing::addr+1
    stx ZERO_2_1
    sta ZERO_2_1+1
    ldy #0
    lda (ZERO_2_1), y
    sta Tile_player_standing::actor

    ; sets the player on the tile
    lda #ACTORS::PLAYER 
    sta (ZERO_2_1), y

    ; restore the given locations
    ldx ZERO_2_4
    ldy ZERO_2_5

    rts

; Destroys ZERO_2_1, ZERO_2_2 and ZERO_2_3
Compute_Maze_Addr:

    stx COORD_X

    ; offset due to Y coord
    sty FAC1
    lda #WIDTH_WORLD
    sta FAC2
    jsr mul8
    tay ; high part of the mul
    txa ; low part of the mul

    ; adding offset due to X
    clc
    adc COORD_X
    sta OFFSET
    tya
    adc #0
    sta OFFSET+1

    ; adding the offset to the address
    lda #<World
    clc
    adc OFFSET
    tax             ; low part of address to be returned in X
    lda #>World
    adc OFFSET+1    ; high part of address to be returned in A

    rts



.DATA

.align 256

World: .res (WIDTH_WORLD) * (HEIGHT_WORLD)
; .byte 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06
; .byte 06, 02, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 06, 06, 06
; .byte 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 06, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06
; .byte 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06
; .byte 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 06, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06
; .byte 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 06
; .byte 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06
; .byte 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06
; .byte 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 02, 02, 02, 02, 02, 02, 06, 06, 06, 02, 02, 02, 06, 06, 06
; .byte 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06, 06