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

package main

import (
	"bytes"
	"errors"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"strings"

	"go.wit.com/lib/fhelp"
	"go.wit.com/lib/protobuf/forgepb"
	"go.wit.com/lib/protobuf/gitpb"
	"go.wit.com/log"
)

func isPatchingSafe() bool {
	if me.forge.Config.Mode == forgepb.ForgeMode_NORMAL {
		return true
	}
	log.Info("This patch command is not safe to run now")
	log.Info("you must reset the state of your git repositories. Run:")
	log.Info("")
	log.Info("forge normal (or use --force)")
	log.Info("")
	if argv.Force {
		return true
	}
	return false
}

func doPatch() error {
	if argv.Patch.Submit != nil {
		return doPatchSubmit()
	}

	if !isPatchingSafe() {
		return log.Errorf("not safe to work on patches")
	}

	if argv.Patch.Get != nil {
		psets := forgepb.NewSets()
		newpb, _, _ := psets.HttpPostVerbose(myServer(), "get")
		doPatchGet(newpb)
		return nil
	}

	if argv.Patch.List != nil {
		err := doPatchList()
		return err
	}

	err := doPatchList()
	return err
}

// submit's current working patches
func doPatchSubmit() error {
	pset, err := me.forge.MakeDevelPatchSet("testing")
	if err != nil {
		return err
	}
	if pset.Patches == nil {
		log.Info("pset.Patches == nil")
		return err
	}
	if pset.Patches.Len() == 0 {
		log.Info("did not find any patches")
		return nil
	}
	pset.PrintTable()
	_, _, err = pset.HttpPost(myServer(), "new")
	return err
}

func doPatchList() error {
	curpatches := forgepb.NewPatches()
	curpatches.Filename = "/tmp/curpatches.pb"
	if err := curpatches.Load(); err != nil {
		return err
	}
	curpatches.PrintTable()
	for patch := range curpatches.IterAll() {
		repo := me.forge.Repos.FindByNamespace(patch.Namespace)
		if repo == nil {
			log.Info("no namespace", patch.PatchId, patch.Namespace, patch.Comment)
			continue
		}
		newId, newHash, err := isPatchIdApplied(repo, patch)
		if errors.Is(err, ErrorGitPullOnDirty) {
			log.Info("a patch with that comment couldn't be found in the repo")
		} else if err != nil {
			log.Info("err", patch.PatchId, patch.Namespace, patch.Comment, err)
			return patch.Error(err)
		}
		if (newId == patch.PatchId) && (newHash == patch.CommitHash) {
			log.Info(patch.PatchId, "patch made here", patch.Comment)
			continue
		}
		if newId == patch.PatchId {
			log.Info(patch.PatchId, "patch already applied", patch.Comment)
			continue
		}
		if newId != patch.PatchId {
			log.Info(patch.PatchId, "probably duplicate subject", patch.Comment)
		}
		log.Info("new patch", patch.PatchId, patch.Comment)
		if !argv.Fix {
			log.Info("use --fix to attempt to apply new patches")
		} else {
			if fhelp.QuestionUser("apply this patch?") {
				newhash, err := applyPatch(repo, patch)
				log.Info("apply results:", newhash, err)
				if err != nil {
					return err
				}
			}
		}
	}
	return nil
}

func applyPatch(repo *gitpb.Repo, p *forgepb.Patch) (string, error) {
	_, filen := filepath.Split(p.Filename)
	tmpname := filepath.Join("/tmp", filen)
	log.Info("saving as", tmpname, p.Filename)
	raw, err := os.OpenFile(tmpname, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
	if err != nil {
		return "", err
	}
	raw.Write(p.Data)
	raw.Close()

	cmd := []string{"git", "am", tmpname}
	err = repo.RunVerbose(cmd)
	if err != nil {
		log.Info("git am failed. run 'git am --abort' here")
		return "", log.Errorf("git am failed")
	}

	log.Info("Try to find hash value now")

	return p.NewHash, log.Errorf("did not lookup new hash")
}

func doPatchGet(newpb *forgepb.Sets) {
	// var changed bool
	curpatches := forgepb.NewPatches()
	curpatches.Filename = "/tmp/curpatches.pb"
	if err := curpatches.Load(); err != nil {
		curpatches.Save()
		curpatches.Save()
		log.Info(err)
		panic("no file")
		// return
		// // THIS IS NEEDED? NOTSURE
		curpatches = forgepb.NewPatches()
		curpatches.Filename = "/tmp/curpatches.pb"
		curpatches.Save()
	}
	// newpb.PrintTable()
	for pset := range newpb.IterAll() {
		if pset.Patches.Len() == 0 {
			log.Info("pset is empty", pset.Name)
			continue
		}
		for patch := range pset.Patches.IterAll() {
			if len(patch.Data) == 0 {
				continue
			}
			patchid, hash, err := gitpb.FindPatchIdFromGitAm(patch.Data)
			if err != nil {
				log.Info("git patchid exec err", err)
				continue
			}
			if hash != patch.CommitHash {
				log.Info("ERROR: patch commit hashes's didn't match", hash, patch.CommitHash)
				continue
			}
			if patchid != patch.PatchId {
				log.Info("ERROR: patchid's didn't match", patchid, patch.PatchId)
				continue
			}
			found := curpatches.FindByPatchId(patch.PatchId)
			if found != nil {
				// already have this patch
				continue
			}
			// gitpb.FindPatchIdFromGitAmBroken(patch.Data) // doesn't os.Exec()
			log.Info("adding new patch", patch.CommitHash, patch.PatchId, patch.Filename)
			curpatches.AppendByPatchId(patch)
		}
	}
	curpatches.Save()
	curpatches.PrintTable()
	// me.forge.Patchsets = newpb
	// me.forge.Patchsets.Save()
}

var ErrorGitPullOnDirty error = errors.New("git comment is not there")

func isPatchIdApplied(repo *gitpb.Repo, patch *forgepb.Patch) (string, string, error) {
	comment := cleanSubject(patch.Comment)

	os.Chdir(repo.GetFullPath())
	newhash, err := findCommitBySubject(comment)
	if err != nil {
		return "", "", ErrorGitPullOnDirty
	}

	patchId, err := repo.FindPatchIdByHash(newhash)
	if err != nil {
		return "", "", err
	}

	// log.Infof("%s %s found hash by comment %s \n", patchId, newhash, patch.Comment)
	return patchId, newhash, nil
}

// Shows repos that are:
//   - git dirty repos
//   - repos with 'user' branch patches not in 'devel' branch
//   - repos with awaiting master branch verions
//
// return true if any are found
func showWorkRepos() bool {
	// always run dirty first
	me.forge.CheckDirtyQuiet()

	// if no option is given to patch, list out the
	// repos that have patches ready in them
	found := findReposWithPatches()
	found.SortNamespace()
	if found.Len() == 0 {
		log.Info("you currently have no repos with patches")
		return false
	} else {
		footer := me.forge.PrintDefaultTB(found)
		log.Info("repos with patches or unsaved changes:", footer)
	}
	return true
}

func cleanSubject(line string) string {
	// Regular expression to remove "Subject:" and "[PATCH...]" patterns
	re := regexp.MustCompile(`(?i)^Subject:\s*(\[\s*PATCH[^\]]*\]\s*)?`)
	cleaned := re.ReplaceAllString(line, "")
	return strings.TrimSpace(cleaned)
}

// jcarr@framebook:~/go/src/go.wit.com/lib/protobuf/forgepb$ git branch --contains 4a27e7702b9b975b066ec9d2ee7ac932d86552e3
// * jcarr
// jcarr@framebook:~/go/src/go.wit.com/lib/protobuf/forgepb$ git merge-base --is-ancestor "4a27e7702b9b975b066ec9d2ee7ac932d86552e3" "devel" ; echo $?
// 1
// jcarr@framebook:~/go/src/go.wit.com/lib/protobuf/forgepb$ git merge-base --is-ancestor "4a27e7702b9b975b066ec9d2ee7ac932d86552e3" "jcarr" ; echo $?
// 0

func findCommitBySubject(subject string) (string, error) {
	cmd := exec.Command("git", "log", "--pretty=format:%H %s", "--grep="+subject, "-i")
	var out bytes.Buffer
	cmd.Stdout = &out
	err := cmd.Run()
	if err != nil {
		return "", err
	}

	lines := strings.Split(out.String(), "\n")
	for _, line := range lines {
		if strings.Contains(strings.ToLower(line), strings.ToLower(subject)) {
			return strings.Fields(line)[0], nil // return the commit hash
		}
	}
	return "", fmt.Errorf("no commit found for subject: %s", subject)
}