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

package main

// auto run protoc with the correct args

import (
	"os"
	"strings"

	"go.wit.com/lib/fhelp"
	"golang.org/x/text/cases"
	"golang.org/x/text/language"
)

// this parses the .proto file and handles anything with `autogenpb: `

func (pf *File) protoParse() error {
	// does the file conform to the standard? (also reads in UUID & Version)
	// if err := pb.hasPluralMessage(pf); err != nil {
	// 	return err
	// }
	// os.Exit(0)

	uuid, version, err := fhelp.ValidProtobuf(pf.Filename)
	if err != nil {
		// the user can bypass this, but it's probably not worth allowing this
		if os.Getenv("PROTOBUF_REGRET") != "true" {
			return err
		}
	}
	pf.Uuid = uuid
	pf.Version = version

	// read in the .proto file
	data, err := os.ReadFile(pf.Filename)
	if err != nil {
		return err
	}

	var curmsg *MsgName

	// parse the proto file for message struct names
	for _, line := range strings.Split(string(data), "\n") {
		if strings.HasPrefix(line, "message ") {
			curmsg = pf.parseForMessage(line)
		}
		// this logic isn't right. find end of message with more bravado
		if strings.HasPrefix(line, "}") {
			curmsg = nil
		}
		if curmsg == nil {
			// log.Info("curmsg == nil", line)
			// can't contiue on nil below here
			continue
		}
		// log.Info("curmsg != nil", line)

		parts := strings.Fields(line)
		msgvar := parseMsgVar(line)
		if msgvar == nil {
			// log.Info("Junk in .proto file? line did not contain a message var:", line)
			continue
		}
		if msgvar.IsRepeated {
			// log.Info("ADDING ITER MAP", curmsg.Name, msgvar.VarType)
			pf.IterMap[curmsg.Name] = msgvar.VarType
		}

		if strings.Contains(line, "autogenpb:sort") {
			newS := cases.Title(language.English, cases.NoLower).String(parts[1])
			// log.Info("Addded Sort:", newS, "in struct", curmsg.Name)
			curmsg.Sort = append(curmsg.Sort, newS)
			msgvar.HasSort = true
		}

		if strings.Contains(line, "autogenpb:unique") {
			newU := parts[1]
			newU = cases.Title(language.English, cases.NoLower).String(newU)
			// log.Info("Added Unique:", newU, "in struct", curmsg.Name)
			curmsg.Unique = append(curmsg.Unique, newU)
			msgvar.HasUnique = true
		}
		curmsg.Vars = append(curmsg.Vars, msgvar)
	}
	pf.makeSortTable()

	// for i, s := range slices.Backward(pf.ToSort) {
	return nil
}

func (pf *File) makeSortTable() {
	pf.sortWhat(pf.Bases)
	pf.sortWhat(pf.Base)

	// everything else
	for _, msg := range pf.MsgNames {
		pf.sortWhat(msg)
	}
}

func (pf *File) sortWhat(msg *MsgName) {
	for _, v := range msg.Vars {
		if !v.IsRepeated {
			continue
		}
		if check := pf.findMsg(v.VarType); check == nil {
			// the VarType must be a struct
			continue
		}
		s := new(Sort)
		s.MsgName = msg.Name
		s.VarType = v.VarType
		s.VarName = v.VarName
		s.Lockname = msg.Lockname
		pf.ToSort = append(pf.ToSort, s)
	}
}

func parseMsgVar(line string) *MsgVar {
	if strings.Contains(line, "//") {
		parts := strings.Split(line, "//")
		if len(parts) == 0 {
			// log.Info("parseMsgVar() nothing line", line)
			return nil
		}
		line = parts[0]
	}
	parts := strings.Fields(line)
	if len(parts) < 3 {
		// log.Info("parseMsgVar() len < 3", parts)
		return nil
	}
	if parts[0] == "message" {
		// this is the struct
		return nil
	}
	v := new(MsgVar)
	if parts[0] == "repeated" {
		v.IsRepeated = true
		v.VarType = parts[1]
		v.VarName = cases.Title(language.English, cases.NoLower).String(parts[2])
		return v
	}
	v.VarType = parts[0]
	v.VarName = cases.Title(language.English, cases.NoLower).String(parts[1])
	return v
}

// looks for mutex and marshal entries
func (pf *File) parseForMessage(line string) *MsgName {
	fields := strings.Fields(line)
	if len(fields) == 0 || fields[0] != "message" {
		return nil
	}
	var msg *MsgName
	msg = new(MsgName)

	base := cases.Title(language.English, cases.NoLower).String(pf.Filebase)
	prefix := "message " + base + "s {" // only look for this for now
	if strings.HasPrefix(line, prefix) {
		pf.Bases = msg
	} else {
		prefix := "message " + base + " {" // only look for this for now
		if strings.HasPrefix(line, prefix) {
			pf.Base = msg
		} else {
			pf.MsgNames = append(pf.MsgNames, msg)
		}
	}

	msgName := cases.Title(language.English, cases.NoLower).String(fields[1])
	// log.Info("found messge:", msgName)
	msg.Name = msgName
	msg.Lockname = pf.Filebase + "Mu" // this should be lowercase. do not export the Mutex
	msg.NeedIter = true

	if strings.Contains(line, "`autogenpb:mutex`") {
		msg.DoMutex = true
		// log.Info("Added Mutex=true:", msg.Name)
	}
	if strings.Contains(line, "`autogenpb:nomutex`") {
		msg.NoMutex = true
		// log.Info("Added Mutex=true:", msg.Name)
	}
	if strings.Contains(line, "`autogenpb:marshal`") {
		msg.DoMarshal = true
		// log.Info("Added Marshal=true:", msg.Name)
	}
	return msg
}