package main

import (
	"crypto/sha256"
	logger "log"
	"strings"

	"gitlab.torproject.org/rgdd/ct/pkg/metadata"
)

// logs select logs that count towards CT-compliance checks.  Logs that don't
// have a description are skipped after printing a warning.
func logs(md metadata.Metadata) (logs []metadata.Log) {
	for _, operators := range md.Operators {
		for _, log := range operators.Logs {
			if log.Description == nil {
				logger.Printf("WARNING: skipping log without description")
				continue
			}
			if log.State == nil {
				continue // skip logs with unknown states
			}
			if log.State.Name == metadata.LogStatePending {
				continue // pending logs do not count towards CT-compliance
			}
			if log.State.Name == metadata.LogStateRetired {
				continue // retired logs are not necessarily reachable
			}
			if log.State.Name == metadata.LogStateRejected {
				continue // rejected logs do not count towards CT-compliance
			}

			logs = append(logs, log)
		}
	}
	return
}

// maxWorkers reduces the number of workers for logs that don't appreciate too
// much parallel fetching (errors), or for which performance is equal or worse.
// Warning: this may be system-dependent, determined "by-hand" on 2023-03-18.
func maxWorkers(log metadata.Log, workers uint64) int {
	if max := 40; strings.Contains(*log.Description, "Argon") && int(workers) > max {
		return max
	}
	if max := 16; strings.Contains(*log.Description, "Google") && int(workers) > max {
		return max
	}
	if max := 4; strings.Contains(*log.Description, "Cloudflare") && int(workers) > max {
		return max
	}
	if max := 12; strings.Contains(*log.Description, "Let's Encrypt") && int(workers) > max {
		return max
	}
	if max := 5; strings.Contains(*log.Description, "Sectigo") && int(workers) > max {
		return max
	}
	if max := 2; strings.Contains(*log.Description, "DigiCert") && int(workers) > max {
		return max
	}
	if max := 2; strings.Contains(*log.Description, "Trust Asia") && int(workers) > max {
		return max
	}
	return int(workers)
}

// proof formats hashes so that they can be passed to the merkle package
func proof(hashes [][]byte) (p [][sha256.Size]byte) {
	for _, hash := range hashes {
		var h [sha256.Size]byte
		copy(h[:], hash)
		p = append(p, h)
	}
	return
}