// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

#include "Demo.h"
#include "DemoCharacter.h"
#include "DemoProjectile.h"
#include "UsableActor.h"

//////////////////////////////////////////////////////////////////////////
// ADemoCharacter

ADemoCharacter::ADemoCharacter(const class FPostConstructInitializeProperties& PCIP)
    : Super(PCIP)
{
    // Set size for collision capsule
    CapsuleComponent->InitCapsuleSize(42.f, 96.0f);

    // set our turn rates for input
    BaseTurnRate = 45.f;
    BaseLookUpRate = 45.f;

    // Create a CameraComponent
    FirstPersonCameraComponent = PCIP.CreateDefaultSubobject<UCameraComponent>(this, TEXT("FirstPersonCamera"));
    FirstPersonCameraComponent->AttachParent = CapsuleComponent;
    FirstPersonCameraComponent->RelativeLocation = FVector(0, 0, 64.f); // Position the camera

    // Default offset from the character location for projectiles to spawn
    GunOffset = FVector(100.0f, 30.0f, 10.0f);

    // Create a mesh component that will be used when being viewed from a '1st person' view (when controlling this pawn)
    Mesh1P = PCIP.CreateDefaultSubobject<USkeletalMeshComponent>(this, TEXT("CharacterMesh1P"));
    Mesh1P->SetOnlyOwnerSee(true);          // only the owning player will see this mesh
    Mesh1P->AttachParent = FirstPersonCameraComponent;
    Mesh1P->RelativeLocation = FVector(0.f, 0.f, -150.f);
    Mesh1P->bCastDynamicShadow = false;
    Mesh1P->CastShadow = false;

    // Note: The ProjectileClass and the skeletal mesh/anim blueprints for Mesh1P are set in the
    // derived blueprint asset named MyCharacter (to avoid direct content references in C++)

    MaxUseDistance = 800;
    bHasNewFocus = true;
}

/*
Performs raytrace to find closest looked-at UsableActor.
*/
AUsableActor* ADemoCharacter::GetUsableInView()
{
    FVector camLoc;
    FRotator camRot;

    if (Controller == NULL)
        return NULL;

    Controller->GetPlayerViewPoint(camLoc, camRot);
    const FVector start_trace = camLoc;
    const FVector direction = camRot.Vector();
    const FVector end_trace = start_trace + (direction * MaxUseDistance);

    FCollisionQueryParams TraceParams(FName(TEXT("")), true, this);
    TraceParams.bTraceAsyncScene = true;
    TraceParams.bReturnPhysicalMaterial = false;
    TraceParams.bTraceComplex = true;

    FHitResult Hit(ForceInit);
    GetWorld()->LineTraceSingle(Hit, start_trace, end_trace, COLLISION_PROJECTILE, TraceParams);

    return Cast<AUsableActor>(Hit.GetActor());
}

/*
Update actor currently being looked at by player.
*/
void ADemoCharacter::Tick(float DeltaSeconds)
{
    Super::Tick(DeltaSeconds);

    if (Controller && Controller->IsLocalController())
    {
        AUsableActor* usable = GetUsableInView();

        // End Focus
        if (FocusedUsableActor != usable)
        {
            if (FocusedUsableActor)
            {
                FocusedUsableActor->EndFocusItem();
            }

            bHasNewFocus = true;
        }

        // Assign new Focus
        FocusedUsableActor = usable;

        // Start Focus.
        if (usable)
        {
            if (bHasNewFocus)
            {
                usable->StartFocusItem();
                bHasNewFocus = false;
            }
        }
    }
}

/*
Runs on Server. Perform "OnUsed" on currently viewed UsableActor if implemented.
*/
void ADemoCharacter::Use_Implementation()
{
    if (FocusedUsableActor)
    {
        FocusedUsableActor->OnUsed(this);
    }
}

bool ADemoCharacter::Use_Validate()
{
    // No special server-side validation performed.
    return true;
}

//////////////////////////////////////////////////////////////////////////
// Input

void ADemoCharacter::SetupPlayerInputComponent(class UInputComponent* InputComponent)
{
    // set up gameplay key bindings
    check(InputComponent);

    InputComponent->BindAction("Use", IE_Pressed, this, &ADemoCharacter::Use);

    InputComponent->BindAction("Jump", IE_Pressed, this, &ACharacter::Jump);

    InputComponent->BindAction("Fire", IE_Pressed, this, &ADemoCharacter::OnFire);
    InputComponent->BindTouch(EInputEvent::IE_Pressed, this, &ADemoCharacter::TouchStarted);

    InputComponent->BindAxis("MoveForward", this, &ADemoCharacter::MoveForward);
    InputComponent->BindAxis("MoveRight", this, &ADemoCharacter::MoveRight);

    // We have 2 versions of the rotation bindings to handle different kinds of devices differently
    // "turn" handles devices that provide an absolute delta, such as a mouse.
    // "turnrate" is for devices that we choose to treat as a rate of change, such as an analog joystick
    InputComponent->BindAxis("Turn", this, &APawn::AddControllerYawInput);
    InputComponent->BindAxis("TurnRate", this, &ADemoCharacter::TurnAtRate);
    InputComponent->BindAxis("LookUp", this, &APawn::AddControllerPitchInput);
    InputComponent->BindAxis("LookUpRate", this, &ADemoCharacter::LookUpAtRate);
}

void ADemoCharacter::OnFire()
{
    // try and fire a projectile
    if (ProjectileClass != NULL)
    {
        const FRotator SpawnRotation = GetControlRotation();
        // MuzzleOffset is in camera space, so transform it to world space before offsetting from the character location to find the final muzzle position
        const FVector SpawnLocation = GetActorLocation() + SpawnRotation.RotateVector(GunOffset);

        UWorld* const World = GetWorld();
        if (World != NULL)
        {
            // spawn the projectile at the muzzle
            World->SpawnActor<ADemoProjectile>(ProjectileClass, SpawnLocation, SpawnRotation);
        }
    }

    // try and play the sound if specified
    if (FireSound != NULL)
    {
        UGameplayStatics::PlaySoundAtLocation(this, FireSound, GetActorLocation());
    }

    // try and play a firing animation if specified
    if(FireAnimation != NULL)
    {
        // Get the animation object for the arms mesh
        UAnimInstance* AnimInstance = Mesh1P->GetAnimInstance();
        if(AnimInstance != NULL)
        {
            AnimInstance->Montage_Play(FireAnimation, 1.f);
        }
    }

}

void ADemoCharacter::TouchStarted(const ETouchIndex::Type FingerIndex, const FVector Location)
{
    // only fire for first finger down
    if (FingerIndex == 0)
    {
        OnFire();
    }
}

void ADemoCharacter::MoveForward(float Value)
{
    if (Value != 0.0f)
    {
        // find out which way is forward
        const FRotator Rotation = GetControlRotation();
        FRotator YawRotation(0, Rotation.Yaw, 0);

        // Get forward vector
        const FVector Direction = FRotationMatrix(YawRotation).GetUnitAxis(EAxis::X);

        // add movement in that direction
        AddMovementInput(Direction, Value);
    }
}

void ADemoCharacter::MoveRight(float Value)
{
    if (Value != 0.0f)
    {
        // find out which way is right
        const FRotator Rotation = GetControlRotation();
        const FRotator YawRotation(0, Rotation.Yaw, 0);

        // Get right vector
        const FVector Direction = FRotationMatrix(YawRotation).GetUnitAxis(EAxis::Y);

        // add movement in that direction
        AddMovementInput(Direction, Value);
    }
}

void ADemoCharacter::TurnAtRate(float Rate)
{
    // calculate delta for this frame from the rate information
    AddControllerYawInput(Rate * BaseTurnRate * GetWorld()->GetDeltaSeconds());
}

void ADemoCharacter::LookUpAtRate(float Rate)
{
    // calculate delta for this frame from the rate information
    AddControllerPitchInput(Rate * BaseLookUpRate * GetWorld()->GetDeltaSeconds());
}