package lifecycle

import (
	"fmt"
	"sort"
	"strings"

	"git.5iot.com/iotlcm-public/iotlcm-worker-svr/internal/model/entity"
	lifecycle "git.5iot.com/iotlcm-public/iotlcm-worker-svr/internal/service/lifecycle"
)

// batchFailureSummary 生成中文失败汇总，替代原先的英文「N SIM cards failed」。
// 形如：共50张，成功28张，失败22张；主要失败原因：当前卡状态不支持该操作
func batchFailureSummary(total, success, fail int, reasons []string) string {
	var builder strings.Builder
	fmt.Fprintf(&builder, "共%d张，成功%d张，失败%d张", total, success, fail)
	if reason := dominantReason(reasons); reason != "" {
		builder.WriteString("；主要失败原因：")
		builder.WriteString(reason)
	}
	return builder.String()
}

// dominantReason 取出现次数最多的失败原因；次数相同时按字典序，保证结果稳定可测。
func dominantReason(reasons []string) string {
	counts := make(map[string]int, len(reasons))
	for _, reason := range reasons {
		trimmed := strings.TrimSpace(reason)
		if trimmed == "" {
			continue
		}
		counts[trimmed]++
	}
	if len(counts) == 0 {
		return ""
	}
	keys := make([]string, 0, len(counts))
	for key := range counts {
		keys = append(keys, key)
	}
	sort.Slice(keys, func(i, j int) bool {
		if counts[keys[i]] != counts[keys[j]] {
			return counts[keys[i]] > counts[keys[j]]
		}
		return keys[i] < keys[j]
	})
	return keys[0]
}

// lifecycleFailureSummary 依据内存中的任务明细生成汇总。
func lifecycleFailureSummary(details []*lifecycle.Detail, success, fail int) string {
	reasons := make([]string, 0, fail)
	for _, detail := range details {
		if detail != nil && strings.TrimSpace(detail.Reason) != "" {
			reasons = append(reasons, detail.Reason)
		}
	}
	return batchFailureSummary(len(details), success, fail, reasons)
}

// storedFailureSummary 依据已落库的批次明细生成汇总（重启批次的复机阶段使用）。
func storedFailureSummary(details []*entity.BatchDetail, success, fail int) string {
	reasons := make([]string, 0, fail)
	for _, detail := range details {
		if detail != nil && strings.TrimSpace(detail.ErrorReason) != "" {
			reasons = append(reasons, detail.ErrorReason)
		}
	}
	return batchFailureSummary(len(details), success, fail, reasons)
}