package pis

import (
	"fmt"
	"sort"
	"strings"

	"git.fjla.uk/owlboard/go-types/pkg/database"
	"git.fjla.uk/owlboard/timetable-mgr/dbAccess"
	"git.fjla.uk/owlboard/timetable-mgr/log"
	"go.uber.org/zap"
	"gopkg.in/yaml.v3"
)

// Process the YAML data to a struct
func processYaml(yamlStr string) (*[]database.PIS, error) {
	var pis []PisData

	// Unmarshal the YAML data into a slice of PisData
	err := yaml.Unmarshal([]byte(yamlStr), &pis)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal YAML: %v", err)
	}

	// Perform deduplication on the entire pis slice
	err = deduplicateCodes(&pis)
	if err != nil {
		return nil, err
	}

	documents, err := convertPisForDatabase(&pis)

	return documents, nil
}

// Deduplicate data in place and return error if failed
func deduplicateCodes(pis *[]PisData) error {
	uniqueStops := make(map[string]bool)
	var dedupedPis []PisData

	for _, data := range *pis {
		stopsKey := stopsToString(data.Stops)

		// If stopsKey does not exist, add to map
		if _, exists := uniqueStops[stopsKey]; !exists {
			uniqueStops[stopsKey] = true
			dedupedPis = append(dedupedPis, data)
		}
	}

	*pis = dedupedPis
	return nil
}

// Join slice elements to a string for comparison
func stopsToString(stops []string) string {
	sort.Strings(stops)
	return strings.Join(stops, ",")
}

// Convert PisData to database.PIS
func convertPisForDatabase(in *[]PisData) (*[]database.PIS, error) {
	var out []database.PIS

	for _, code := range *in {
		var document database.PIS
		document.Code = code.Code
		document.Operator = code.Operator
		document.Stops = code.Stops
		document.Tiplocs = GetTiplocsFromCrs(code.Stops)

		out = append(out, document)
	}

	return &out, nil
}

// Return a list of TIPLOCS from a list of CRS using Database Lookups
func GetTiplocsFromCrs(crsList []string) (TiplocList []string) {
	for _, crs := range crsList {
		alpha := strings.ToUpper(crs)
		tiploc, err := dbAccess.GetTiplocFromCrs(alpha)

		if err != nil {
			log.Warn("Unable to find matching TIPLOC for 3ALPHA", zap.String("3ALPHA", alpha), zap.Error(err))
			return
		}

		TiplocList = append(TiplocList, strings.ToUpper(tiploc))
	}

	return
}