module main

import hash.fnv1a
import hash as wyhash
import rand
import benchmark

fn main() {
    rand.seed([u32(42), 0])
    sample_size := 10000000
    min_str_len := 20
    max_str_len := 40
    println('Generating ${sample_size} strings between ${min_str_len} - ${max_str_len} chars long...')
    mut checksum := u64(0)
    mut start_pos := 0
    mut bgenerating := benchmark.start()
    mut bytepile := []u8{}
    for _ in 0 .. sample_size * max_str_len {
        bytepile << u8(rand.int_in_range(40, 125) or { 40 })
    }
    mut str_lens := []int{}
    for _ in 0 .. sample_size {
        str_lens << rand.int_in_range(min_str_len, max_str_len) or { min_str_len }
    }
    bgenerating.measure('generating strings')
    println('Hashing each of the generated strings...')

    mut bhashing_1 := benchmark.start()
    start_pos = 0
    checksum = 0
    for len in str_lens {
        end_pos := start_pos + len
        checksum ^= wyhash.wyhash_c(unsafe { &u8(bytepile.data) + start_pos }, u64(len), 1)
        start_pos = end_pos
    }
    bhashing_1.measure('wyhash.wyhash_c  | checksum: ${checksum:22}')
    mut bhashing_2 := benchmark.start()
    start_pos = 0
    checksum = 0
    for len in str_lens {
        end_pos := start_pos + len
        checksum ^= wyhash.sum64(bytepile[start_pos..end_pos], 1)
        start_pos = end_pos
    }
    bhashing_2.measure('wyhash.sum64     | checksum: ${checksum:22}')
    mut bhashing_3 := benchmark.start()
    start_pos = 0
    checksum = 0
    for len in str_lens {
        end_pos := start_pos + len
        checksum ^= fnv1a.sum64(bytepile[start_pos..end_pos])
        start_pos = end_pos
    }
    bhashing_3.measure('fnv1a.sum64      | checksum: ${checksum:22}')
}