//------------------------------------------------------------------------------
// File: collide.c
// Author: George Bain,
// Date: May 24, 1997
// Description: Collision detection routines for game
// Copyright (C) 1997 George Bain, All Rights Reserved
//------------------------------------------------------------------------------

//------------------------------------------------------------------------------
// I N C L U D E S
//------------------------------------------------------------------------------

#include <libps.h>	// standard Sony library
#include "gfx.h"
#include "collide.h"


//------------------------------------------------------------------------------
// Function: EnemyLeftCollide()
// Description: Check if player has collided with one of the enemies
//              moving to the left of the screen
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void EnemyLeftCollide( void )
 {

   int count;  // loop var
   	   
   object_ptr current;  // current enemy 

   // check if player is ALIVE
   if( player.state == PLAYER_ALIVE )
	 {
       // check against all enemies
	   for( count=0; count<NUM_ENEMIES; count++ )
		  {
		    // check if enemy is ALIVE
		    if( blue_enemy[count].state == ENEMY_ALIVE )
			  {
		        // extract current enemy
			    current = (object_ptr)&blue_enemy[count];

			    // test for collision
			    if( SpriteCollision( (object_ptr)&player, 
						          (object_ptr)&blue_enemy[count]) )
			      {
                    // there's a hit..kill enemy
			        current->state = ENEMY_DEAD;  
                  
				    // start some explosions
			        StartExplosions( current->sprite.x+10, 
							         current->sprite.y+10, 
								     EXPLOSION_SPEED );
				    StartExplosions( player.sprite.x+10, 
							         player.sprite.y+10, 
								     EXPLOSION_SPEED );
				  
				    // decrease players score       
				    game_info.player_energy -= 5; 
				    break;
				  
			      }// end collision

		      }// end if ENEMY_ALIVE
	     
	      }// end for NUM_ENEMIES

	 }// end if PLAYER_ALIVE

 }// end EnemyLeftCollide




//------------------------------------------------------------------------------
// Function: EnemyRightCollide()
// Description: Check if player has collided with one of the enemies
//              moving to the right of the screen
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void EnemyRightCollide( void )
 {

   int count;  // loop var
   	   
   object_ptr current;  // current enemy 

   // check if player is ALIVE
   if( player.state == PLAYER_ALIVE )
	 {
       // check against all enemies
	   for( count=0; count<NUM_ENEMIES; count++ )
		  {
		    // check if enemy is ALIVE
		    if( red_enemy[count].state == ENEMY_ALIVE )
			  {
		        // extract current enemy
			    current = (object_ptr)&red_enemy[count];

			    // test for collision
			    if( SpriteCollision( (object_ptr)&player, 
						          (object_ptr)&red_enemy[count]) )
			      {
                    // there's a hit..kill enemy
			        current->state = ENEMY_DEAD;  
                  
				    // start some explosions
			        StartExplosions( current->sprite.x+10, 
							         current->sprite.y+10, 
								     EXPLOSION_SPEED );
				    StartExplosions( player.sprite.x+10, 
							         player.sprite.y+10, 
								     EXPLOSION_SPEED );
				  
				    // decrease players score       
				    game_info.player_energy -= 5; 
				    break;
				  
			      }// end collision

		      }// end if ENEMY_ALIVE
	     
	      }// end for NUM_ENEMIES

	 }// end if PLAYER_ALIVE

 }// end EnemyRightCollide




//------------------------------------------------------------------------------
// Function: PowerUpCollide()
// Description: Check if player has collided with one of the power ups,
//              if player does collide perform certain actions
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void PowerUpCollide( void )
 {

	int count,
		delta_x, delta_y;

	object_ptr power_one,     // increase players health
			   power_two,     // destroy all enemies on screen
			   power_three;   // increase players lifes

    power_one = (object_ptr)&power_up[0];
	power_two = (object_ptr)&power_up[1];
	power_three = (object_ptr)&power_up[2];

	// check if player is ALIVE
	if( player.state == PLAYER_ALIVE )
	  {
	    // check if first powerup is ALIVE
		if( power_one->state  == POWERUP_ALIVE ) 
		  {
			// test for collision 
			if( SpriteCollision( (object_ptr)&player, 
						         (object_ptr)&power_up[0]) )
			  {
                // a hit!.. kill powerup
				power_one->state = POWERUP_DEAD;  

				// make sure player isn't already full
				if( game_info.player_energy <= PLAYER_ENERGY )
					game_info.player_energy += 100;    // increase energy
			
			  }// end collision

		  }// end if first

		// check if second powerup is ALIVE
		if( power_two->state  == POWERUP_ALIVE ) 
		  {
			// test for collision  
		    if( SpriteCollision( (object_ptr)&player, 
						         (object_ptr)&power_up[1]) )
			  {
				// a hit!.. kill powerup    
				power_two->state = POWERUP_DEAD; 

				// check if any enemies are ALIVE
				for( count=0; count<NUM_ENEMIES; count++ ) 
				   {
					 // destroy enemy if ALIVE
					 if( (red_enemy[count].state == ENEMY_ALIVE) ||
					     (blue_enemy[count].state == ENEMY_ALIVE) ||
						 (boss_one.state == ENEMY_ALIVE ) )
					   {
                         // destroy all enemies
						 red_enemy[count].state = ENEMY_DEAD;
						 blue_enemy[count].state = ENEMY_DEAD;
                             
						 // start some explosions
						 StartExplosions( red_enemy[count].sprite.x+10,
									      red_enemy[count].sprite.y+10, 
										  EXPLOSION_SPEED );
					     StartExplosions( blue_enemy[count].sprite.x+10,
										  blue_enemy[count].sprite.y+10,
									      EXPLOSION_SPEED );
						 
						 // boss energy goes down a bit and explode
                         game_info.boss_energy -= 10;

						 StartExplosions( boss_one.sprite.x+10,
										  boss_one.sprite.y+10,
									      EXPLOSION_SPEED );
						    
					   }// end if ENEMY ALIVE

			       }// end for NUM_ENEMIES

			  }// end if collision

		  }// end if second ALIVE

	    // check if third powerup is ALIVE
		if( power_three->state  == POWERUP_ALIVE ) 
		  {
			// test for collision  
			if( SpriteCollision( (object_ptr)&player, 
						         (object_ptr)&power_up[2]) )
			  {
                // a hit!.. kill powerup    
				power_three->state = POWERUP_DEAD;  

				 // increase players lifes
				game_info.player_lives += 1; 

			  }// end if collision

		  }// end if third ALIVE

    }// end if PLAYER_ALIVE

 }// end PowerUpCollide



 
//------------------------------------------------------------------------------
// Function: BossOneCollide()
// Description: Check if player has collided with the Boss
// Parameters: none
// Returns: void
// Notes: N/A
//------------------------------------------------------------------------------

void BossOneCollide( void )
 {
 
	// check if player and boss is ALIVE
	if( (player.state == PLAYER_ALIVE) && (boss_one.state  == BOSS_ALIVE) )
	  {
        // test for collision
		if( SpriteCollision( (object_ptr)&player, 
						     (object_ptr)&boss_one) )
		  {
				 
		    // decrease energy 
			game_info.boss_energy -= 15;  
		    game_info.player_energy -= 10;

			// start explosions
			StartExplosions( player.sprite.x+10, 
						     player.sprite.y+10, 
							 EXPLOSION_SPEED );
			StartExplosions( boss_one.sprite.x+10, 
						     boss_one.sprite.y+10, 
							 EXPLOSION_SPEED );
					 
		  }// end collision

	  }// end if player ALIVE

 }// end BossOneCollide


//-----------------------------------EOF----------------------------------------