#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include <math.h>

#include <raylib.h>
#include <raymath.h>

#include "types.h"
#include "map.h"
#include "game.h"
#include "lua_inter.h"

MachineDef machine_dict[] = {
  {{{0,0},{32,0},{0,32},{32,32}}, {},               0, R_Coal,  4}, // MT_CoalMine
  {{{0,0},{32,0},{0,32},{32,32}}, {},               0, R_Iron,  4}, // MT_IronMine
  {{{0,0},{32,0},{0,32},{32,32}}, {R_Coal, R_Iron}, 2, R_Steel, 0}, // MT_Furnace 
};

int init_machines(Machines *machines){
  machines->machine_n = 0;
  machines->machine_id = 0;

  machines->machine_stack = malloc(sizeof(Worker)*W_ALLOC_BLOCK);
  if(!machines->machine_stack)
    return 1;

  return 0;
}

int init_workers(Workers *workers){
  workers->worker_n = 0;

  workers->worker_stack = malloc(sizeof(Worker)*W_ALLOC_BLOCK);
  if(!workers->worker_stack)
    return 1;

  return 0;
}

int init_game(Game *game){
  int rand_seed = GetTime();
  rand_seed &= 0xFFFFFFFF;

  srand(rand_seed);

  game->paused = true;
  game->exit = false;
  game->ttime = 0;
  game->camera = (Camera2D){.offset = {0, 0}, .zoom = 1};

  int err = init_machines(&game->machines);
  err |= init_workers(&game->workers);
  if(err){
    printf("Failed to init game. Error : %x\n", err);
    return 1;
  }

  int c_worker = 0;

  for(int k = 0; k < 16; k++){
    for(int j = 0; j < 16; j++){
      Machine *coal_mine = add_machine(&game->machines, (V2d){k*250+40,j*400+40});
      coal_mine->type = MT_CoalMine;
      Machine *iron_mine = add_machine(&game->machines, (V2d){k*250+40,j*400+240});
      iron_mine->type = MT_IronMine;
      Machine *furnace = add_machine(&game->machines, (V2d){k*250+140,j*400+140});
      furnace->type = MT_Furnace;

      for(int i = 0; i < 10; i++)
        add_worker(&game->workers, (V2d){.x=k*250+100,.y=j*400});
      for(int i = 0; i < 4; i++)
        assign_worker_machine(coal_mine, &game->workers.worker_stack[c_worker++]);
      for(int i = 4; i < 8; i++)
        assign_worker_machine(iron_mine, &game->workers.worker_stack[c_worker++]); 
      assign_worker_fetch(iron_mine, furnace, &game->workers.worker_stack[c_worker++]);
      assign_worker_fetch(coal_mine, furnace, &game->workers.worker_stack[c_worker++]);
      if(!(furnace->id%1000))
        printf("%d\n",furnace->id);
    }
  }

  return 0;
}

void clean_machines(Machines *machines){
  free(machines->machine_stack);
}

void clean_workers(Workers *workers){
  free(workers->worker_stack);
}

void clean_game(Game *game){
  clean_machines(&game->machines);
  clean_workers(&game->workers);
  clean_map(game);
}

Worker *add_worker(Workers *workers, V2d pos){
  if((workers->worker_n%W_ALLOC_BLOCK)+1 >= W_ALLOC_BLOCK){
    void *tmp = realloc(workers->worker_stack, 
                          (workers->worker_n+W_ALLOC_BLOCK)*sizeof(Worker));
    if(!tmp){
      printf("Failed to extend worker stack !\n");
      return NULL;
    }

    workers->worker_stack = tmp;
  }

  Worker *work = &workers->worker_stack[workers->worker_n++];
  work->pos = pos;
  work->ai = (AiInternal){S_Idle, 0, 0, 0, MACH_NULL, MACH_NULL, {.x=0,.y=0}};

  return work;
}

Machine *add_machine(Machines *machines, V2d pos){
  if((machines->machine_n%M_ALLOC_BLOCK)+1 >= M_ALLOC_BLOCK){
    void *tmp = realloc(machines->machine_stack, 
                          (machines->machine_n+W_ALLOC_BLOCK)*sizeof(Machine));
    if(!tmp){
      printf("Failed to extend machine stack !\n");
      return NULL;
    }

    machines->machine_stack = tmp;
  }

  if(machines->machine_id == MACH_NULL){
    printf("Max machines reached !\n");
    return NULL;
  }

  Machine *mach = &machines->machine_stack[machines->machine_n++];
  *mach = (Machine){.pos=pos};
  mach->id = machines->machine_id++;

  return mach;
}

int id_cmpfunc(const void *a_, const void *b_){
  const Machine *a = a_;
  const Machine *b = b_;
  return a->id - b->id;
}

Machine *get_machine_from_id(Machines *machines, uint16_t id){
  Machine tmach = {.id = id};
  Machine *match = bsearch(&tmach, machines->machine_stack, machines->machine_n,
                            sizeof(Machine), &id_cmpfunc);
  return match;
}

int get_machine_localres(Machine *machine, int globalres){
  MachineDef *def = &machine_dict[machine->type];
  for(int i = 0; i < 4; i++){
    if(def->inputs[i] == globalres)
      return i;
  }
  return -1;
}

Worker *get_worker_from_pos(Workers *workers, V2d pos){
  Worker *match = NULL;

  for(int i = 0; i < workers->worker_n; i++){
    Worker *curr = &workers->worker_stack[i];
    if(CheckCollisionPointRec(pos, 
             (Rectangle){.x=curr->pos.x,.y=curr->pos.y,.width=32,.height=32})){
      match = curr;
      break;
    }
  }

  return match;
}

Machine *get_machine_from_pos(Machines *machines, V2d pos){
  Machine *match = NULL;

  for(int i = 0; i < machines->machine_n; i++){
    Machine *curr = &machines->machine_stack[i];
    if(CheckCollisionPointRec(pos, 
             (Rectangle){.x=curr->pos.x,.y=curr->pos.y,.width=64,.height=64})){
      match = curr;
      break;
    }
  }
  return match;
}

void update_worker(Game *game, Worker *worker){
  AiInternal *ai = &worker->ai;

  Machine *mach[2] = {0};
  //MachineDef *defs[2];

  if(ai->assigned_machine != MACH_NULL){
    mach[0] = get_machine_from_id(&game->machines, ai->assigned_machine);
    if(!mach[0])
      ai->assigned_machine = MACH_NULL;
    else{
      //defs[0] = &machine_dict[mach[0]->type];
      ai->mtype = mach[0]->type;
    }
  }
  if(ai->assigned_machine1 != MACH_NULL){
    mach[1] = get_machine_from_id(&game->machines, ai->assigned_machine1);
    if(!mach[1])
      ai->assigned_machine1 = MACH_NULL;
    /*else
      defs[1] = &machine_dict[mach[1]->type];
    */
  }

  if(ai->assigned_machine == MACH_NULL && ai->assigned_machine1 == MACH_NULL)
    ai->status = S_Idle;

  int localres;
  Vector2 mov;

  //TODO : Move !
  switch(ai->status){
    default:
    case S_Idle:
      break;
    case S_Loading:
      if(!Vector2Equals(worker->pos,mach[0]->pos)){
        ai->status = S_Transporting;
        ai->dest = mach[0]->pos;
        break;
      }
      if(ai->carrying <= 50 && mach[0]->storage[4]){
        ai->carrying++;
        mach[0]->storage[4]--;
      }
      else {
        ai->status = S_Transporting;
        ai->dest = mach[1]->pos;
      }
      break;
    case S_Unloading:
      localres = get_machine_localres(mach[1], ai->carry_type);
      if(localres != (int)ai->carry_type){
        ai->status = S_Idle;
        break;
      }
      if(!Vector2Equals(worker->pos, mach[1]->pos)){
        ai->status = S_Transporting;
        ai->dest = mach[1]->pos;
        break;
      }
      if(ai->carrying && mach[1]->storage[localres] <= 200){
        ai->carrying--;
        mach[1]->storage[localres]++;
      }
      else{
        ai->status = S_Transporting;
        ai->dest = mach[0]->pos;
      }
      break;
    case S_Operating:
      worker->pos = mach[0]->pos;
      break;
    case S_Transporting:
    case S_Walking:
      mov = Vector2Scale(
                      Vector2Normalize(Vector2Subtract(ai->dest, worker->pos)),
                      2
                    );
      worker->pos = Vector2Add(worker->pos, mov);
      if(Vector2LengthSqr(Vector2Subtract(mach[0]->pos, worker->pos)) < 0.5){
        worker->pos = mach[0]->pos;
        ai->status = S_Loading;
      }
      else if(Vector2LengthSqr(Vector2Subtract(mach[1]->pos, worker->pos))
                < 0.5){
        worker->pos = mach[1]->pos;
        ai->status = S_Unloading;
      }
      break;
  }
}

void update_workers(Game *game){
  for(int i = 0; i < game->workers.worker_n; i++){
    update_worker(game, &game->workers.worker_stack[i]);
  }
}

void update_machine(Game *game, Machine *machine){
  MachineDef *def = &machine_dict[machine->type];
  bool can_output = machine->assign_workers == def->workers_required;
  can_output = can_output && (machine->storage[4] <= 200);
  for(int i = 0; i < def->input_n; i++){
    if(!machine->storage[i])
      can_output = false;
  }
  if(can_output){ 
    for(int i = 0; i < def->input_n; i++){
      machine->storage[i]--;
    }
    machine->storage[4]++;
    if(machine->active < 252)
      machine->active+=4;
  }
  else if(machine->active > 1)
    machine->active-=2;
}

void update_machines(Game *game){
  for(int i = 0; i < game->machines.machine_n; i++){
    update_machine(game, &game->machines.machine_stack[i]);
  }
}

void update(Game *game){
  game->t_per_frame = 0;

  if(game->paused)
    return;

  lua_onframe(game);

  game->ttime += GetFrameTime();

  while(game->ttime > TPS_TIME){
    lua_ontick(game);
    update_machines(game);
    update_workers(game);
    game->ttime -= TPS_TIME;
    game->t_per_frame++;
  }
}

int assign_worker_machine(Machine *machine, Worker *worker){
  worker->assign_n = machine->assign_workers++;
  AiInternal *ai = &worker->ai;
  ai->assigned_machine = machine->id;
  ai->assigned_machine1 = MACH_NULL;
  ai->status = S_Operating;
  worker->pos = machine->pos;
  return 0;
}

int assign_worker_fetch(Machine *a, Machine *b, Worker *worker){
  AiInternal *ai = &worker->ai;
  ai->carry_type = machine_dict[a->type].output;
  ai->assigned_machine = a->id;
  ai->assigned_machine1 = b->id;
  ai->status = S_Loading;
  return 0;
}