package projectinstance

import (
	"fmt"

	"chat-agent-system/internal/workflowdef"
)

func validatePlan(plan WorkflowPlan, version *workflowdef.Version) workflowdef.ValidationResult {
	issues := make([]workflowdef.ValidationIssue, 0)
	if version == nil {
		return workflowdef.ValidationResult{
			Valid: false,
			Issues: []workflowdef.ValidationIssue{{
				Code: "WORKFLOW_VERSION_NOT_FOUND", Message: "工作流版本不存在或未发布",
			}},
		}
	}
	if version.Status != workflowdef.StatusPublished {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "WORKFLOW_NOT_PUBLISHED", Message: "只能绑定已发布的工作流版本",
		})
	}
	if !workflowdef.IsOfficialWorkflowKey(plan.WorkflowDefinitionKey) {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "WORKFLOW_NOT_SELECTABLE", Field: "workflow_definition_key",
			Message: "仅允许选择正式三工作流",
		})
	}
	if plan.WorkflowDefinitionKey != version.WorkflowKey {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "WORKFLOW_KEY_MISMATCH", Field: "workflow_definition_key",
			Message: fmt.Sprintf("规划 key %s 与版本 %s 不一致", plan.WorkflowDefinitionKey, version.WorkflowKey),
		})
	}
	if plan.WorkflowVersion != version.Version {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "WORKFLOW_VERSION_MISMATCH", Field: "workflow_version",
			Message: fmt.Sprintf("规划版本 %d 与已发布版本 %d 不一致", plan.WorkflowVersion, version.Version),
		})
	}

	stageDefMap := make(map[string]workflowdef.StageDef, len(version.Definition.Stages))
	for _, st := range version.Definition.Stages {
		stageDefMap[st.Key] = st
	}
	seenStage := map[string]bool{}
	for _, st := range plan.Stages {
		if seenStage[st.StageKey] {
			issues = append(issues, workflowdef.ValidationIssue{
				Code: "DUPLICATE_STAGE", Field: st.StageKey, Message: "阶段 key 重复",
			})
			continue
		}
		seenStage[st.StageKey] = true
		def, ok := stageDefMap[st.StageKey]
		if !ok {
			issues = append(issues, workflowdef.ValidationIssue{
				Code: "UNKNOWN_STAGE", Field: st.StageKey, Message: "阶段不在工作流定义中",
			})
			continue
		}
		if !def.Optional && !st.Enabled {
			issues = append(issues, workflowdef.ValidationIssue{
				Code: "REQUIRED_STAGE_DISABLED", Field: st.StageKey, Message: "必需阶段不能关闭",
			})
		}
		taskDefMap := make(map[string]workflowdef.DocTaskDef, len(def.DocTasks))
		for _, dt := range def.DocTasks {
			taskDefMap[dt.Key] = dt
		}
		seenTask := map[string]bool{}
		for _, dt := range st.DocTasks {
			if seenTask[dt.TaskKey] {
				issues = append(issues, workflowdef.ValidationIssue{
					Code: "DUPLICATE_DOC_TASK", Field: dt.TaskKey, Message: "文档任务 key 重复",
				})
				continue
			}
			seenTask[dt.TaskKey] = true
			td, ok := taskDefMap[dt.TaskKey]
			if !ok {
				issues = append(issues, workflowdef.ValidationIssue{
					Code: "UNKNOWN_DOC_TASK", Field: dt.TaskKey, Message: "文档任务不在阶段定义中",
				})
				continue
			}
			if !dt.Enabled && !td.IsCreatorConfigurable() {
				issues = append(issues, workflowdef.ValidationIssue{
					Code: "REQUIRED_DOC_DISABLED", Field: dt.TaskKey, Message: "该文档任务不可由创建者关闭",
				})
			}
			if dt.Enabled {
				issues = append(issues, validateDuties(dt.Duties, dt.TaskKey)...)
			}
		}
	}

	enabledStages := 0
	for _, st := range plan.Stages {
		if st.Enabled {
			enabledStages++
		}
	}
	if enabledStages == 0 {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "NO_ENABLED_STAGE", Message: "至少启用一个阶段",
		})
	}

	return workflowdef.ValidationResult{Valid: len(issues) == 0, Issues: issues}
}

func validateActivationPlan(plan WorkflowPlan, version *workflowdef.Version) workflowdef.ValidationResult {
	base := validatePlan(plan, version)
	if !base.Valid {
		return base
	}
	if countEnabledDocTasks(plan) == 0 {
		base.Valid = false
		base.Issues = append(base.Issues, workflowdef.ValidationIssue{
			Code: "EMPTY_WORKFLOW", Message: "至少启用一个文档任务才能激活工作流",
		})
	}
	return base
}

func countEnabledDocTasks(plan WorkflowPlan) int {
	n := 0
	for _, st := range plan.Stages {
		if !st.Enabled {
			continue
		}
		for _, dt := range st.DocTasks {
			if dt.Enabled {
				n++
			}
		}
	}
	return n
}

func validateDuties(d DocDuty, taskKey string) []workflowdef.ValidationIssue {
	issues := make([]workflowdef.ValidationIssue, 0)
	if d.AuthorUserID <= 0 {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "DUTY_AUTHOR_REQUIRED", Field: taskKey + ".author",
			Message: "启用的文档任务必须指定作者",
		})
	}
	if d.ReviewerUserID <= 0 {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "DUTY_REVIEWER_REQUIRED", Field: taskKey + ".reviewer",
			Message: "启用的文档任务必须指定审核人",
		})
	}
	if d.ApproverUserID <= 0 {
		issues = append(issues, workflowdef.ValidationIssue{
			Code: "DUTY_APPROVER_REQUIRED", Field: taskKey + ".approver",
			Message: "启用的文档任务必须指定批准人",
		})
	}
	ids := []int64{d.AuthorUserID, d.ReviewerUserID, d.ApproverUserID}
	for i := 0; i < len(ids); i++ {
		if ids[i] <= 0 {
			continue
		}
		for j := i + 1; j < len(ids); j++ {
			if ids[j] > 0 && ids[i] == ids[j] {
				issues = append(issues, workflowdef.ValidationIssue{
					Code: "SEPARATION_OF_DUTY_VIOLATION", Field: taskKey,
					Message: "作者、审核人、批准人必须分离",
				})
				return issues
			}
		}
	}
	return issues
}

func buildDefaultPlan(version *workflowdef.Version) WorkflowPlan {
	plan := WorkflowPlan{
		WorkflowDefinitionKey: version.WorkflowKey,
		WorkflowVersion:       version.Version,
		WorkflowVersionID:     version.ID,
		Stages:                make([]StagePlan, 0, len(version.Definition.Stages)),
	}
	for _, st := range version.Definition.Stages {
		sp := StagePlan{
			StageKey:  st.Key,
			StageName: st.Name,
			Enabled:   !st.Optional,
			DocTasks:  make([]DocTaskPlan, 0, len(st.DocTasks)),
		}
		for _, dt := range st.DocTasks {
			sp.DocTasks = append(sp.DocTasks, DocTaskPlan{
				TaskKey:   dt.Key,
				TaskTitle: dt.Title,
				Enabled:   dt.DefaultEnabled,
			})
		}
		plan.Stages = append(plan.Stages, sp)
	}
	return plan
}

// applyDefinitionLabels 使用已发布定义覆盖展示名称，避免客户端把自定义文本写入冻结快照。
func applyDefinitionLabels(plan *WorkflowPlan, version *workflowdef.Version) {
	if plan == nil || version == nil {
		return
	}
	stageDefs := make(map[string]workflowdef.StageDef, len(version.Definition.Stages))
	for _, stage := range version.Definition.Stages {
		stageDefs[stage.Key] = stage
	}
	for stageIdx := range plan.Stages {
		stage := &plan.Stages[stageIdx]
		stageDef, ok := stageDefs[stage.StageKey]
		if !ok {
			continue
		}
		stage.StageName = stageDef.Name
		taskDefs := make(map[string]workflowdef.DocTaskDef, len(stageDef.DocTasks))
		for _, task := range stageDef.DocTasks {
			taskDefs[task.Key] = task
		}
		for taskIdx := range stage.DocTasks {
			task := &stage.DocTasks[taskIdx]
			if taskDef, exists := taskDefs[task.TaskKey]; exists {
				task.TaskTitle = taskDef.Title
			}
		}
	}
}

func previewSummary(plan WorkflowPlan, version *workflowdef.Version) PreviewSummary {
	sum := PreviewSummary{
		WorkflowVersion: plan.WorkflowVersion,
	}
	if version != nil {
		sum.WorkflowName = version.WorkflowName
		if sum.WorkflowName == "" {
			sum.WorkflowName = version.WorkflowKey
		}
	}
	for _, st := range plan.Stages {
		if !st.Enabled {
			continue
		}
		sum.EnabledStages++
		if sum.FirstStageKey == "" {
			sum.FirstStageKey = st.StageKey
			if version != nil {
				for _, sd := range version.Definition.Stages {
					if sd.Key == st.StageKey {
						sum.FirstStageName = sd.Name
						break
					}
				}
			}
		}
		for _, dt := range st.DocTasks {
			if !dt.Enabled {
				continue
			}
			sum.EnabledDocTasks++
			if dt.Duties.AuthorUserID > 0 {
				sum.AssignedDuties++
			}
			if dt.Duties.ReviewerUserID > 0 {
				sum.AssignedDuties++
			}
			if dt.Duties.ApproverUserID > 0 {
				sum.AssignedDuties++
			}
		}
	}
	return sum
}