extern crate json;
extern crate rand;
extern crate serde;
extern crate serde_json;
#[macro_use]
extern crate serde_derive;

mod actions;
mod math;
mod files;
mod ships;
mod placement;
mod shooting;
mod state;
mod knowledge;

use actions::*;
use math::*;
use files::*;
use ships::*;
use placement::*;
use shooting::*;
use state::*;
use knowledge::*;

use std::path::PathBuf;

pub fn write_move(working_dir: PathBuf) -> Result<(), String> {
    let state_json = read_file(&working_dir)?;

    let is_place_phase = state_json["Phase"] == 1;
    let map_size = State::map_size_from_json(&state_json)?;

    let (action, knowledge) = if is_place_phase {
        placement(map_size)
    }
    else {
        let state = State::new(&state_json)?;
        shoot(&state)?
    };
    
    write_knowledge(&knowledge)
        .map_err(|e| format!("Failed to write knowledge to file. Error: {}", e))?;
        
    write_action(&working_dir, is_place_phase, action)
        .map_err(|e| format!("Failed to write action to file. Error: {}", e))?;

    println!("Knowledge:\n{}\n\n", serde_json::to_string(&knowledge).unwrap_or(String::from("")));
    
    Ok(())
}

fn placement(map_size: u16) -> (Action, Knowledge) {
    let action = place_ships_randomly(map_size);
    let knowledge = Knowledge::new(map_size, action.clone());

    (action, knowledge)
}

fn shoot(state: &State) -> Result<(Action, Knowledge), String> {
    let old_knowledge = read_knowledge()?;
    let knowledge = old_knowledge.resolve_last_action(&state);
    let action = shoot_smartly(&knowledge);
    
    Ok((action.clone(), knowledge.with_action(action)))
}