// Package logger define log struct of modelRT project
package logger

import (
	"context"
	"path"
	"runtime"

	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

type logger struct {
	ctx     context.Context
	traceID string
	spanID  string
	pSpanID string
	_logger *zap.Logger
}

func (l *logger) Debug(msg string, kv ...any) {
	l.log(zapcore.DebugLevel, msg, kv...)
}

func (l *logger) Info(msg string, kv ...any) {
	l.log(zapcore.InfoLevel, msg, kv...)
}

func (l *logger) Warn(msg string, kv ...any) {
	l.log(zapcore.WarnLevel, msg, kv...)
}

func (l *logger) Error(msg string, kv ...any) {
	l.log(zapcore.ErrorLevel, msg, kv...)
}

func (l *logger) log(lvl zapcore.Level, msg string, kv ...any) {
	fields := makeLogFields(l.ctx, kv...)
	ce := l._logger.Check(lvl, msg)
	ce.Write(fields...)
}

func makeLogFields(ctx context.Context, kv ...any) []zap.Field {
	// Ensure that log information appears in pairs in the form of key-value pairs
	if len(kv)%2 != 0 {
		kv = append(kv, "unknown")
	}

	kv = append(kv, "traceID", ctx.Value("traceID"), "spanID", ctx.Value("spanID"), "pspanID", ctx.Value("pspanID"))

	funcName, file, line := getLoggerCallerInfo()
	kv = append(kv, "func", funcName, "file", file, "line", line)
	fields := make([]zap.Field, 0, len(kv)/2)
	for i := 0; i < len(kv); i += 2 {
		key := kv[i].(string)
		value := kv[i+1]
		switch v := value.(type) {
		case string:
			fields = append(fields, zap.String(key, v))
		case int:
			fields = append(fields, zap.Int(key, v))
		case int64:
			fields = append(fields, zap.Int64(key, v))
		case float32:
			fields = append(fields, zap.Float32(key, v))
		case float64:
			fields = append(fields, zap.Float64(key, v))
		case bool:
			fields = append(fields, zap.Bool(key, v))
		case error:
			fields = append(fields, zap.Error(v))
		default:
			fields = append(fields, zap.Any(key, v))
		}
	}
	return fields
}

// getLoggerCallerInfo define func of return log caller information、method name、file name、line number
func getLoggerCallerInfo() (funcName, file string, line int) {
	pc, file, line, ok := runtime.Caller(4)
	if !ok {
		return
	}
	file = path.Base(file)
	funcName = runtime.FuncForPC(pc).Name()
	return
}

func New(ctx context.Context) *logger {
	var traceID, spanID, pSpanID string
	if ctx.Value("traceID") != nil {
		traceID = ctx.Value("traceID").(string)
	}
	if ctx.Value("spanID") != nil {
		spanID = ctx.Value("spanID").(string)
	}
	if ctx.Value("psapnID") != nil {
		pSpanID = ctx.Value("pspanID").(string)
	}

	return &logger{
		ctx:     ctx,
		traceID: traceID,
		spanID:  spanID,
		pSpanID: pSpanID,
		_logger: GetLoggerInstance(),
	}
}