package bizdev

import (
	"context"
	"strings"

	"chat-agent-system/internal/docduty"
	"chat-agent-system/internal/docgov"

	"github.com/jackc/pgx/v5/pgxpool"
)

func resolveTaskDocumentDuties(ctx context.Context, pool *pgxpool.Pool, req TaskRunRequest, instanceDuty InstanceDutySource) (docduty.Binding, string, bool) {
	if instanceDuty != nil && req.ProjectID > 0 && strings.TrimSpace(req.TaskKey) != "" {
		authorID, reviewerID, approverID, dutyPolicy, governed, err := instanceDuty.ResolveGovernedDuty(ctx, req.ProjectID, req.TaskKey)
		if err == nil && governed {
			bound := docduty.Binding{
				Author:   docduty.Holder{UserID: authorID},
				Reviewer: docduty.Holder{UserID: reviewerID},
				Approver: docduty.Holder{UserID: approverID},
			}
			if pool != nil {
				if members, creator, loadErr := docduty.LoadProjectMembers(ctx, pool, req.ProjectID); loadErr == nil {
					bound.Author.Name = holderName(members, creator, authorID, req.AuthorName)
					bound.Reviewer.Name = holderName(members, creator, reviewerID, req.ReviewerName)
					bound.Approver.Name = holderName(members, creator, approverID, req.ApproverName)
				}
			}
			if bound.Author.Name == "" {
				bound.Author.Name = strings.TrimSpace(req.AuthorName)
			}
			if bound.Reviewer.Name == "" {
				bound.Reviewer.Name = strings.TrimSpace(req.ReviewerName)
			}
			if bound.Approver.Name == "" {
				bound.Approver.Name = strings.TrimSpace(req.ApproverName)
			}
			return bound, dutyPolicy, true
		}
	}

	reqDuties := docduty.RequestDuties{
		AuthorID: req.AuthorID, AuthorName: req.AuthorName,
		ReviewerID: req.ReviewerID, ReviewerName: req.ReviewerName,
		ApproverID: req.ApproverID, ApproverName: req.ApproverName,
	}
	if reqDuties.AuthorID == 0 {
		reqDuties.AuthorID = req.UserID
	}
	if pool != nil && req.ProjectID > 0 {
		if bound, err := docduty.ResolveProject(ctx, pool, req.ProjectID, reqDuties); err == nil {
			if bound.Author.UserID == 0 && req.UserID > 0 {
				bound.Author = docduty.Holder{UserID: req.UserID, Name: strings.TrimSpace(req.AuthorName)}
			}
			return bound, "", false
		}
	}
	creator := docduty.Holder{UserID: req.UserID, Name: strings.TrimSpace(req.AuthorName)}
	return docduty.Resolve(nil, creator, reqDuties), "", false
}

func holderName(members []docduty.Member, creator docduty.Holder, userID int64, fallback string) string {
	if userID <= 0 {
		return strings.TrimSpace(fallback)
	}
	if creator.UserID == userID && strings.TrimSpace(creator.Name) != "" {
		return strings.TrimSpace(creator.Name)
	}
	for _, m := range members {
		if m.UserID == userID && strings.TrimSpace(m.Name) != "" {
			return strings.TrimSpace(m.Name)
		}
	}
	return strings.TrimSpace(fallback)
}

func lineageVersion(doc *docgov.DocumentRecord) int {
	if doc != nil && doc.Version > 0 {
		return doc.Version
	}
	return 1
}

func bindingFromDoc(doc *docgov.DocumentRecord) docduty.Binding {
	if doc == nil {
		return docduty.Binding{}
	}
	return docduty.Binding{
		Author:   docduty.Holder{UserID: doc.AuthorID, Name: doc.AuthorName},
		Reviewer: docduty.Holder{UserID: doc.ReviewerID, Name: doc.ReviewerName},
		Approver: docduty.Holder{UserID: doc.ApproverID, Name: doc.ApproverName},
	}
}

func writeBindingToDoc(doc *docgov.DocumentRecord, bound docduty.Binding) {
	if doc == nil {
		return
	}
	doc.AuthorID, doc.AuthorName = bound.Author.UserID, bound.Author.Name
	doc.ReviewerID, doc.ReviewerName = bound.Reviewer.UserID, bound.Reviewer.Name
	doc.ApproverID, doc.ApproverName = bound.Approver.UserID, bound.Approver.Name
}