package utils

import (
	"crypto/sha256"
	"fmt"
	"os"

	"git.cs.kau.se/rasmoste/ct-sans/internal/merkle"
	"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 {
				fmt.Fprintf(os.Stderr, "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
}

// 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
}

// LeafHashes formats a list of data as leaf hashes
func LeafHashes(data [][]byte) (lh [][sha256.Size]byte) {
	for _, d := range data {
		lh = append(lh, merkle.HashLeafNode(d))
	}
	return
}