// Copyright 2017-2025 WIT.COM Inc. All rights reserved.
// Use of this source code is governed by the GPL 3.0

package main

import (
	"errors"
	"strings"

	"go.wit.com/lib/cobol"
	"go.wit.com/lib/env"
	"go.wit.com/lib/protobuf/argvpb"
	"go.wit.com/lib/protobuf/gitpb"
	"go.wit.com/log"
	"google.golang.org/protobuf/types/known/timestamppb"
)

func doStats(cmd *StatsCmd) (string, error) {
	var allerr error
	if argv.All {
		for r := range me.forge.Repos.IterByFullPath() {
			if r.Stats().Len() == 0 {
				_, err := doStatsRepo(r)
				allerr = errors.Join(allerr, err)
			}
		}
		return "verify ran everywhere", nil
	}

	repo := workingDirToRepo()
	if repo == nil {
		return "no repo", errors.New("working dir isn't a repo I know about")
	}

	if cmd.List {
		s := repo.Stats()
		s.SortPatchId()
		// s.SortCtime()
		footer := s.PrintTableLimit(-1)
		return "stats table: " + footer, nil
	}

	s, err := doStatsRepo(repo)
	allerr = errors.Join(allerr, err)

	user, err := refHash(repo, "heads/"+repo.GetUserBranchName())
	allerr = errors.Join(allerr, err)
	master, err := refHash(repo, "remotes/origin/master")
	allerr = errors.Join(allerr, err)
	HEAD, err := refHash(repo, "remotes/origin/HEAD")
	allerr = errors.Join(allerr, err)
	log.Printf("user=%10.10s master=%10.10s HEAD=%10.10s\n", user, master, HEAD)

	safeDelete(repo, "refs/heads/"+repo.GetUserBranchName(), "refs/remotes/origin/HEAD") // delete user if safely contained in HEAD
	safeDelete(repo, user, HEAD)                                                         // checkes by hash ID                                   // delete user if safely contained in HEAD

	return s, allerr
}

func doStatsRepo(r *gitpb.Repo) (string, error) {
	var allerr error
	pb, err := r.LoadStats()
	if err == nil {
		log.Info("LoadStats() ok", pb.Filename)
	} else {
		log.Info("LoadStats() err", err)
	}
	allerr = errors.Join(allerr, err)

	if hasOrigin(r) {
		log.Info("todo: detect origin")
	}

	// collect the stats
	counter, err := last100(r, pb)
	allerr = errors.Join(allerr, err)
	s := log.Sprintf("found %d new hashes", counter)

	for stat := range pb.IterAll() {
		if stat.PatchId == "" {
			stat.PatchId, err = r.FindPatchIdByHash(stat.Hash)
			allerr = errors.Join(allerr, err)
			log.Info("patchid for hash", stat.Hash, "is", stat.PatchId)
			counter += 1
		}
	}

	if counter > 0 {
		pb.SaveVerbose()
	}
	return s, nil
}

func collectStats(r *gitpb.Repo, pb *gitpb.Stats) error {
	return nil
}

// git show-ref refs/heads/devel
func refHash(r *gitpb.Repo, name string) (string, error) {
	var hash string
	refname := "refs/" + name
	cmd := []string{"git", "show-ref", refname}
	cmdout := r.Run(cmd)
	for i, line := range cmdout.Stdout {
		parts := strings.Fields(line)
		if env.If("stats") {
			log.Info(parts[0], "LINE:", i, line)
		}
		hash = parts[0]
	}
	if len(cmdout.Stdout) != 1 {
		return "", errors.New("no refname:" + name)
	}
	return hash, nil
}

// git show-ref --verify refs/heads/devel
func hasOrigin(r *gitpb.Repo) bool {
	// git show-ref refs/heads/devel
	return true
}

var standardFmts []string = []string{"H", "T", "at", "ct", "f"}
var standardSeperator string = "___FORGE___"

func makeFmts() string {
	// fmts := strings.Fields(config.GetPanic("standardFmts"))
	// fmts := strings.Fields(config.GetPanic("standardSeperator"))
	var all []string
	for _, fmtvar := range standardFmts {
		all = append(all, "%"+fmtvar)
	}
	return "--format=" + strings.Join(all, standardSeperator)
}

// the correct syntax for
// git log -n 8 --format=%H%00%ae%00%as%00%s origin/HEAD
func last100(r *gitpb.Repo, pb *gitpb.Stats) (int, error) {
	var allerr error
	var counter int
	cmd := []string{"git", "log", "-n", "100", makeFmts(), "origin/" + r.GetMasterBranchName()} // must use 'master' as queried from the git server
	// cmd := []string{"git", "log", "-n", "100", makeFmts(), "origin/HEAD"} // HEAD is _NOT_ always set
	if env.If("stats") {
		log.Info("Run:", cmd)
	}
	cmdout := r.Run(cmd)
	for i, line := range cmdout.Stdout {
		parts := strings.Split(line, standardSeperator)
		hash := parts[0]
		if env.If("stats") {
			log.Printf("LINE:%8.8s %2d %v\n", hash, i, parts[1:])
		}
		found := pb.FindByHash(hash)
		if found != nil {
			// already have this hash
			continue
		}
		counter += 1
		astat := new(gitpb.Stat)
		astat.Hash = hash
		ctime, err := cobol.GetTime(parts[2])
		allerr = errors.Join(allerr, err)
		astat.Ctime = timestamppb.New(*ctime)
		astat.Subject = parts[4]
		astat.Type = gitpb.Stat_REMOTE
		pb.Append(astat)
	}
	return counter, allerr
}

func findPatchIdInStats(pb *gitpb.Stats, patchId string) *gitpb.Stat {
	for stat := range pb.IterAll() {
		if stat.PatchId == patchId {
			return stat
		}
	}
	// log.Info("findPatchId searched in", pb.Len(), "stats")
	return nil
}

// delete localRef if it's completely contained in the masterRef
func safeDelete(r *gitpb.Repo, deleteHash string, keepHash string) error {
	// compare the branches
	hashok, hashbad, cmd1, cmd2, err := r.CompareHashes(keepHash, deleteHash)

	if err != nil {
		// things are really really messed up. might be 'branchless' at this point (?)
		log.Printf("%-13.13s %-55.55s err='%v' %s %v\n", "CMD ERR", r.FullPath, err, "NOT SAFE TO DELETE. Reload()?", cmd1)
		log.Printf("%-13.13s %-55.55s err='%v' %s %v\n", "CMD ERR", r.FullPath, err, "NOT SAFE TO DELETE. Reload()?", cmd2)
		return err
	}

	// things only in the master branch (safe to ignore)
	for _, line := range hashok {
		parts := strings.Split(line, "%00") // git log doesn't actually convert %00 to NULL
		patchId, err := r.FindPatchIdByHash(parts[0])
		_ = err
		log.Printf("%-13.13s %-55.55s hId %10.10s pId %10.10s %v\n", "OK delete", r.FullPath, parts[0], patchId, parts[2:])
	}

	if len(hashbad) > 0 {
		log.Printf("%-13.13s %v\n", "BAD cmd", cmd1)
	}
	var ACTUALLYOK bool = true
	// things still only in the local branch (bad to delete)
	for _, line := range hashbad {
		parts := strings.Split(line, "%00") // git log doesn't actually convert %00 to NULL
		patchId, err := r.FindPatchIdByHash(parts[0])
		_ = err
		searchResult := log.Sprintf("NOPE(%d)", r.Stats().Len())
		stat := findPatchIdInStats(r.Stats(), patchId)
		if stat != nil {
			searchResult = log.Sprintf("FOUND %10.10s %s", stat.PatchId, stat.Subject)
		} else {
			ACTUALLYOK = false
		}

		log.Printf("%-13.13s %-55.55s hId %10.10s pId %10.10s %s %v\n", "BAD keep", r.FullPath, parts[0], patchId, searchResult, parts[2:])
	}

	if ACTUALLYOK {
		// todo: force checkout to local master branch
		// before doing this
		cmd := []string{"git", "update-ref", "-d", deleteHash}
		// log.Printf("%-13.13s %-55.55s %v %s\n", "CMD OK", r.FullPath, cmd1, "")
		// log.Printf("%-13.13s %-55.55s %v %s\n", "CMD OK", r.FullPath, cmd2, "")
		if r.GetCurrentBranchName() == r.GetMasterBranchName() {
			log.Printf("%-55.55s %v %s\n", r.FullPath, cmd, "SAFE TO DELETE add --fix")
		} else {
			log.Printf("%-55.55s %v %s\n", r.FullPath, cmd, "SAFE TO DELETE BUT NOT ON MASTER BRANCH add --fix")
		}
		if argv.Fix {
			err := r.RunVerbose(cmd)
			if err != nil {
				log.Info(deleteHash, r.FullPath)
				s := "local user branch could not be deleted"
				argvpb.BadExit(s, err)
			}
		}
		return ErrorNeedArgvFix
	}

	return log.Errorf("NOT SAFE")
}