use crate::prelude::*;

// #[derive(Debug)]
pub struct Point {
    x: i32,
    y: i32,
}

pub struct Population {
    pub start_infected_ratio: i32,
    pub start_immune_ratio: i32,
    pub start_dead_ratio: i32,
    pub humans: Vec<Human>,
    pub width: i32,
    pub height: i32,
    pub age: i32,
    pub plague: Disease,
}

pub fn human_idx(x: i32, y: i32, width: i32) -> usize {
    ((y * width) + x) as usize
}

impl Population {
    pub fn new(
        start_infected_ratio: i32,
        start_immune_ratio: i32,
        start_dead_ratio: i32,
        width: i32,
        height: i32,
        plague: Disease,
    ) -> Self {
        let mut the_humans: Vec<Human> = Vec::with_capacity((width * height) as usize);
        for x in 0..width {
            for y in 0..height {
                the_humans.push(Human::new(x, y));
            }
        }
        Self {
            start_infected_ratio: start_infected_ratio,
            start_immune_ratio: start_immune_ratio,
            start_dead_ratio: start_dead_ratio,
            width: width,
            height: height,
            plague: plague,
            age: 0,
            humans: the_humans,
        }
    }
    // pub fn change_disease(&mut self, plague:Disease){
    //     self.plague = plague;
    // }
    pub fn generate(&mut self) {
        //The ratios will not be exact, for example someone who wants 100% infected 100% immune and 100% dead, he will have 100% dead because they are overwriting each others
        //Maybe consider limiting the total to not exceed 100 in the view
        //Other thing, there will always be more of the last one because someone who is already infected for example could be then put to immune or dead
        //One solution to this issue would be to have if else else statements but in this case for example 20% would be lower with the last because its 20% on the remaining population and not of the all
        //In other words I did it that way but it can be changed just its not the right method to have perfect ratios
        let mut rng = rand::thread_rng();

        for x in self.humans.iter_mut() {
            if (self.start_infected_ratio) > 0
                && (rng.gen_range(0..CORRECTED_PERCENTAGE) <= self.start_infected_ratio as i32)
            {
                x.present_state = State::Infected;
            } else if self.start_immune_ratio > 0
                && rng.gen_range(0..CORRECTED_PERCENTAGE) <= self.start_immune_ratio as i32
            {
                x.present_state = State::Immune;
            } else if self.start_dead_ratio > 0
                && rng.gen_range(0..CORRECTED_PERCENTAGE) <= self.start_dead_ratio as i32
            {
                x.present_state = State::Dead;
            }
        }
    }

    pub fn propagate(&mut self) -> [i32; 4] {
        let mut people_to_check: Vec<Point> =
            Vec::with_capacity((self.width * self.height) as usize);
        let mut people_to_infect: Vec<Point> =
            Vec::with_capacity((self.width * self.height) as usize);
        let mut people_to_cure: Vec<Point> =
            Vec::with_capacity((self.width * self.height) as usize);
        let mut people_to_kill: Vec<Point> =
            Vec::with_capacity((self.width * self.height) as usize);
        let mut stats: [i32; 4] = [0, 0, 0, 0];
        // stats[0] Normal stats[1] Infected stats[2] Immune stats[3] Dead

        for h in self.humans.iter() {
            match h.present_state {
                State::Normal => {
                    stats[0] += 1;
                }
                State::Infected => {
                    people_to_check.push(Point { x: h.x, y: h.y });
                    stats[1] += 1;
                }
                State::Immune => {
                    stats[2] += 1;
                }
                State::Dead => {
                    stats[3] += 1;
                }
            }
        }
        println!("{} people to check, death rate {}", people_to_check.len(), self.plague.death_rate);
        //        for pos in &people_to_check {
        for pos in people_to_check.iter() {
            //people_to_check.iter().map(|pos|{
            //get all the other people next to me and check if i die cure or infect
            //now we can start to check if people would be infected or not
            //let idx = human_idx(pos.x as i32, pos.y as i32, self.width as i32);
            if pos.x >= 0 && pos.x <= self.width - 1 && pos.y >= 0 && pos.y <= self.height - 1 {
                if roll(self.plague.curing_rate) {
                    //checks if the man recovers
                    people_to_cure.push(Point { x: pos.x, y: pos.y });
                } else {

                    if roll(self.plague.death_rate) {
                        //cheks if the man dies
                        people_to_kill.push(Point { x: pos.x, y: pos.y });
                    } else {
                        let mut possible_infections: Vec<Point> = Vec::with_capacity(8);
                        // Vec::new();
                        //possible_infections.push(Point{x:pos.x,y:pos.y});

                        if pos.x > 0 && pos.y > 0 {
                            possible_infections.push(Point {
                                x: pos.x - 1,
                                y: pos.y - 1,
                            }); //Top Left
                        }
                        if pos.y > 0 {
                            possible_infections.push(Point {
                                x: pos.x,
                                y: pos.y - 1,
                            }); //Top
                        }
                        if pos.y > 0 && pos.x < self.width - 1 {
                            possible_infections.push(Point {
                                x: pos.x + 1,
                                y: pos.y - 1,
                            }); //Top Right
                        }
                        if pos.x > 0 {
                            possible_infections.push(Point {
                                x: pos.x - 1,
                                y: pos.y,
                            }); //Left
                        }
                        if pos.x < self.width - 1{
                            possible_infections.push(Point {
                                x: pos.x + 1,
                                y: pos.y,
                            }); //Right
                        }
                        if pos.x > 0 && pos.y < self.height -1 {
                            possible_infections.push(Point {
                                x: pos.x - 1,
                                y: pos.y + 1,
                            }); //Bottom Left
                        }
                        if pos.y < self.height - 1 {
                            possible_infections.push(Point {
                                x: pos.x,
                                y: pos.y + 1,
                            }); //Bottom
                        }
                        if pos.x < self.width - 1 && pos.y < self.height - 1{
                            possible_infections.push(Point {
                                x: pos.x + 1,
                                y: pos.y + 1,
                            }); //Bottom Right
                        }
                        for poss_infected_pos in possible_infections.iter() {
                            //possible_infections.iter().map(|poss_infected_pos|{
                            let inf_idx =
                                human_idx(poss_infected_pos.x, poss_infected_pos.y, self.width);
                            if self.humans[inf_idx].present_state == State::Normal {
                                if roll(self.plague.infection_rate) {
                                    people_to_infect.push(Point {
                                        x: poss_infected_pos.x,
                                        y: poss_infected_pos.y,
                                    });
                                }
                            }
                        }
                    }
                }
            } else {
                //TODO
                //Check every special cases (corners sides etc..)

                //REMOVE WHEN IMPLEMENTED
                //It is here to prevent an infected in the borders to keep the programm running as he thinks there are still people to simulate
                //people_to_kill.push(Point { x: pos.x, y: pos.y });

                //    @##
                //    ###
                //    ###

                //    #@#
                //    ###
                //    ###

                //    ##@
                //    ###
                //    ###

                //    ###
                //    @##
                //    ###

                //    ###
                //    ##@
                //    ###

                //    ###
                //    ###
                //    @##

                //    ###
                //    ###
                //    #@#

                //    ###
                //    ###
                //    ##@
            }
        }
        println!(
            "{} to infect, {} to cure, {} to kill",
            people_to_infect.len(),
            people_to_cure.len(),
            people_to_kill.len()
        );
        for infected_position in &people_to_infect {
            // println!("To infect: {:?}", infected_position);
            //people_to_infect.iter().map(|infected_position|{
            let infected_index = human_idx(infected_position.x, infected_position.y, self.width);
            // let _ = infected_position.x;
            //DEBUG
            //println!("x: {} y: {} index: {}",infected_position.x,infected_position.y,infected_index);
            self.humans[infected_index].present_state = State::Infected;
            //DEBUG
            //println!("Infected someone");
        }

        for cured_position in &people_to_cure {
            //people_to_cure.iter().map(|cured_position|{
            let cured_index = human_idx(cured_position.x, cured_position.y, self.width);
            self.humans[cured_index].present_state = State::Immune;
            //DEBUG
            //println!("Cured someone");
        }

        for dead_position in &people_to_kill {
            //people_to_kill.iter().map(|dead_position|{
            let dead_index = human_idx(dead_position.x, dead_position.y, self.width);
            if self.humans[dead_index].present_state == State::Dead {
                // println!("Already dead");
            } else {
                self.humans[dead_index].present_state = State::Dead;
            }
            //DEBUG
        }
        assert_eq!(stats[0] + stats[1] + stats[2] + stats[3], self.humans.len() as i32);
        stats
    }

    // pub fn display(&mut self){
    //     let sprite = "#";
    //     print!("\n");
    //     for x in 0..self.width{
    //         for y in 0..self.height{
    //             let index = human_idx(x as i32,y as i32,self.width as i32);
    //             match self.humans[index].present_state {
    //                 State::Normal => print!("{}",style(sprite).green()),
    //                 State::Dead => print!("{}",style(sprite).black()),
    //                 State::Infected => print!("{}",style(sprite).red()),
    //                 State::Immune => print!("{}",style(sprite).blue()),
    //                 _ => print!("{}",style(sprite).white()),
    //             }
    //         }
    //         print!("\n");
    //     }
    // }
}

pub fn roll(probability: i32) -> bool {
    if probability > 0 {
        let mut rng = rand::thread_rng();
        rng.gen_range(0 as i32..CORRECTED_PERCENTAGE) <= probability
    } else {
        false
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use parameterized::parameterized;

    #[derive(Debug)]
    struct Stats {
        normal: i32,
        infected: i32,
        immune: i32,
        dead: i32,
    }

    impl Stats {
        fn new() -> Stats {
            Stats {
                normal: 0,
                infected: 0,
                immune: 0,
                dead: 0,
            }
        }
    }

    fn humans_stats(humans: &Vec<Human>) -> Stats {
        let mut stats: Stats = Stats::new();
        for human in humans.iter() {
            match human.present_state {
                State::Normal => {
                    stats.normal += 1;
                }
                State::Infected => {
                    stats.infected += 1;
                }
                State::Immune => {
                    stats.immune += 1;
                }
                State::Dead => {
                    stats.dead += 1;
                }
            }
        }
        stats
    }

    #[parameterized(x = {
        2, 3, 5
    }, y = {
        1, 4, 0
    }, width = {
        3, 5, 7
    }, res = {
        5, 23, 5
    })]
    fn test_human_idx(x: i32, y: i32, width: i32, res: usize) {
        assert_eq!(human_idx(x, y, width), res);
    }

    #[test]
    fn test_human_stats() {
        let mut humans: Vec<Human> = Vec::with_capacity(10);
        let mut stats: Stats;

        for _ in 0..10 {
            humans.push(Human::new(0, 0));
        }
        stats = humans_stats(&humans);
        assert_eq!(stats.normal, 10);

        for x in 0..2 {
            humans[x].present_state = State::Infected;
        }
        for x in 2..5 {
            humans[x].present_state = State::Immune;
        }
        for x in 5..9 {
            humans[x].present_state = State::Dead;
        }
        stats = humans_stats(&humans);
        assert_eq!(stats.normal, 1);
        assert_eq!(stats.infected, 2);
        assert_eq!(stats.immune, 3);
        assert_eq!(stats.dead, 4);
    }

    #[test]
    fn population_new() {
        let disease = Disease::new(20, 10, 5, String::from("Covid 44"));
        let population = Population::new(20, 10, 5, 5, 7, disease);
        assert_eq!(population.humans.len(), 5 * 7);
        for human in population.humans.iter() {
            assert!(
                human.present_state == State::Normal,
                "all humans should be normal"
            );
        }
    }

    #[test]
    fn population_gen() {
        let disease = Disease::new(20, 10, 5, String::from("Covid 44"));
        let (width, height) = (5, 7);
        let mut population = Population::new(20, 10, 5, 5, 7, disease);

        population.generate();
        let stats: Stats = humans_stats(&population.humans);
        println!("Stats: {:?}", stats);

        assert_eq!(
            stats.normal + stats.infected + stats.immune + stats.dead,
            width * height
        );
    }

    #[test]
    fn plague_init_stats() {
        let mut disease: Disease;
        let mut population: Population;
        let mut stats: Stats;
        let (width, height) = (5, 7);

        disease = Disease::new(0, 0, 0, String::from("Test"));
        population = Population::new(0, 0, 0, width, height, disease);
        population.generate();
        stats = humans_stats(&population.humans);
        println!("should be normal: {:?}", stats);
        assert_eq!(stats.normal, width * height);

        disease = Disease::new(0, 0, 0, String::from("Test"));
        population = Population::new(100, 0, 0, width, height, disease);
        population.generate();
        stats = humans_stats(&population.humans);
        println!("should be infected: {:?}", stats);
        assert_eq!(stats.infected, width * height);

        disease = Disease::new(0, 0, 0, String::from("Test"));
        population = Population::new(0, 100, 0, width, height, disease);
        population.generate();
        stats = humans_stats(&population.humans);
        println!("should be immune: {:?}", stats);
        assert_eq!(stats.immune, width * height);

        disease = Disease::new(0, 0, 0, String::from("Test"));
        population = Population::new(0, 0, 100, width, height, disease);
        population.generate();
        stats = humans_stats(&population.humans);
        println!("should be dead: {:?}", stats);
        assert_eq!(stats.dead, width * height);
    }

    #[parameterized(rate = {0, 100}, expected = {false, true})]
    fn roll_test(rate: i32, expected: bool) {
        let tries = 100000;
        let mut result = 0;
        println!("Testing roll, rate {}, expected {}", rate, expected);
        for _x in 0..tries {
            if roll(rate) == expected {
                result += 1;
            }
        }
        assert_eq!(result, tries);
    }

    #[test]
    fn propagate_simple() {
        let disease: Disease = Disease::new(0, 0, 100, String::from("Deadly"));
        let mut population: Population = Population::new(100, 0, 0, 10, 10, disease);
        let mut stats: Stats;

        stats = humans_stats(&population.humans);
        println!("stats after init: {:?}", stats);
        assert_eq!(stats.normal, 100);
        population.generate();
        stats = humans_stats(&population.humans);
        println!("stats after generate: {:?}", stats);
        assert_eq!(stats.infected, 100);
    }

    #[parameterized(infection_rate = {0, 100, 0}, death_rate = {0, 0, 100}, infected_expected = {0, 1, 0})]
    fn propagate_test(infection_rate: i32, death_rate: i32, infected_expected: i32) {
        let disease: Disease;
        let mut population: Population;
        let mut stats: Stats;
        let (width, height) = (100, 100);
        let start_infected = 50;

        println!(
            "infection rate: {}, death_rate: {}",
            infection_rate, death_rate
        );

        disease = Disease::new(infection_rate, 0, death_rate, String::from("Test"));
        population = Population::new(start_infected, 0, 0, width, height, disease);

        population.generate();
        stats = humans_stats(&population.humans);
        println!("Population after generate: {:?}", stats);

        // total * proba - 20% < infected < total * proba + 20%
        let infected_at_start_proba = width * height * start_infected / 100;
        let infected_tolerance = ((width * height) as f32 * 0.2) as i32;
        assert!(stats.infected <= infected_at_start_proba + infected_tolerance);
        assert!(stats.infected >= infected_at_start_proba - infected_tolerance);
        assert_eq!(stats.dead, 0);

        for _x in 0..100 {
            let infected_at_start = stats.infected;
            let dead_at_start = stats.dead;

            let propa_stats: [i32; 4] = population.propagate();

            assert!(propa_stats[3] >= dead_at_start);

            if death_rate == 0 {
                assert_eq!(propa_stats[3], 0, "no human should have died");
            }

            stats = humans_stats(&population.humans);
            println!("Population after propagate: {:?}", stats);

            assert!(stats.normal <= infected_at_start + width * height * infected_expected);

            let should_be_dead = infected_at_start * death_rate / 100;
            let dead_tolerance = (should_be_dead as f32 * 0.20) as i32;

            assert!(
                stats.dead <= should_be_dead + dead_tolerance,
                "death count should be less or equal than {}",
                should_be_dead + dead_tolerance
            );
            assert!(stats.dead >= should_be_dead - dead_tolerance);
        }
    }
}