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import gleam/float
import gleam/io
import gleam/list
import gleam/regex
import gleam/result
import gleam/string
import simplifile
pub type Star {
Star(name: String, x: Float, y: Float, z: Float)
}
pub fn main() {
let assert Ok(data) = simplifile.read(from: "./src/day4/data.txt")
let assert [_, ..stars] = string.split(data, "\n")
stars
|> list.map(parse_star_record)
|> list.combination_pairs()
|> list.map(star_distance)
|> list.reduce(float.min)
|> io.debug
}
fn parse_star_record(str: String) -> Star {
let assert Ok(re) = regex.from_string("\\s{2,}")
let assert [name, ..coords] = regex.split(with: re, content: str)
let assert [_, x, y, z] =
coords
|> list.map(float.parse)
|> result.values
Star(name, x, y, z)
}
fn star_distance(stars: #(Star, Star)) -> Float {
let #(star1, star2) = stars
let assert Ok(dist) =
float.square_root(
sq(star1.x -. star2.x) +. sq(star1.y -. star2.y) +. sq(star1.z -. star2.z),
)
dist
}
fn sq(x: Float) -> Float {
x *. x
}
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