package cif

import (
	"bytes"
	"encoding/json"

	"git.fjla.uk/owlboard/go-types/pkg/upstreamApi"
	"git.fjla.uk/owlboard/timetable-mgr/log"
	"go.uber.org/zap"
)

// Unmarshalls data into the correct types for processing
func parseCifData(data []byte) (*parsedData, error) {
	// Split the data into lines
	lines := bytes.Split(data, []byte("\n"))

	// Initialise variable for the parsed data
	var parsed parsedData
	parsed.assoc = make([]upstreamApi.JsonAssociationV1, 0)
	parsed.sched = make([]upstreamApi.JsonScheduleV1, 0)

	for _, line := range lines {

		// Skip empty lines to avoid logging errors when there is no error
		if len(bytes.TrimSpace(line)) == 0 {
			continue
		}

		// Map each line for processing
		var obj map[string]json.RawMessage
		if err := json.Unmarshal(line, &obj); err != nil {
			log.Msg.Error("Error decoding line", zap.String("line", string(line)), zap.Error(err))
			continue
		}

		// Loop through the mapped data and unmarshal to the correct type
		for key, value := range obj {
			switch key {
			case "JsonTimetableV1":
				var timetable upstreamApi.JsonTimetableV1
				if err := json.Unmarshal(value, &timetable); err != nil {
					log.Msg.Error("Unable to parse JSON Timetable", zap.Error(err), zap.String("line", string(value)))
					continue
				}
				parsed.header = timetable
			case "JsonAssociationV1":
				var association upstreamApi.JsonAssociationV1
				if err := json.Unmarshal(value, &association); err != nil {
					log.Msg.Error("Error decoding JSON Association", zap.Error(err))
					continue
				}
				parsed.assoc = append(parsed.assoc, association)
			case "JsonScheduleV1":
				var schedule upstreamApi.JsonScheduleV1
				if err := json.Unmarshal(value, &schedule); err != nil {
					log.Msg.Error("Error decoding JSON Schedule", zap.Error(err))
					continue
				}
				parsed.sched = append(parsed.sched, schedule)
			}
		}
	}
	return &parsed, nil
}