package utils

import (
	"errors"
	"regexp"
)

// HandleRegexp handles a regex with named capture groups.
// If the given regexp does not have any named capture group, or if no match is found, an error is returned
// Matches are returned as a map which keys are the capture groups names
func HandleRegexp(dat string, pattern regexp.Regexp) (res []map[string]string, err error) {
	namedGroups := 0
	for _, n := range pattern.SubexpNames() {
		if n != "" {
			namedGroups++
		}
	}
	if namedGroups == 0 {
		return nil, errors.New("no named subgroup in pattern")
	}

	matches := pattern.FindAllStringSubmatch(dat, -1)
	if matches == nil {
		return nil, errors.New("no match found")
	}
	res = make([]map[string]string, 0)

	for _, line := range matches {
		subMatchMap := make(map[string]string)
		for i, name := range pattern.SubexpNames() {
			if i != 0 {
				subMatchMap[name] = string(line[i])
			}
		}
		res = append(res, subMatchMap)
	}
	return
}

// HandleKeyValRegexRes merges a list of maps containing result as a key/value format
//
// Input maps all have the following format:
//
//	{
//		"key": "some_key",
//		"value": "some_val",
//	}
//
// Final result will have the format
//
//	{
//		"some_key": "some_val",
//	}
func HandleKeyValRegexRes(rawMatches []map[string]string) map[string]string {
	matchedMap := make(map[string]string)
	for _, m := range rawMatches {
		currKey := ""
		currVal := ""
		for k, v := range m {
			if k == "key" {
				currKey = v
			} else if k == "value" {
				currVal = v
			}
			// All other keys are ignored
			// Should not happen given the given regexp
		}
		if currKey != "" && currVal != "" {
			matchedMap[currKey] = currVal
		}
	}
	return matchedMap
}