package scale

import (
	"context"
	"encoding/json"
	"errors"

	"github.com/google/uuid"

	sc "github.com/yuxingu/digital-psychology/apps/api/internal/scale"
	"github.com/yuxingu/digital-psychology/apps/api/internal/scalebank"
	"github.com/yuxingu/digital-psychology/apps/api/internal/repository"
)

// ErrMembershipRequired when full MBTI requires growth membership.
var ErrMembershipRequired = errors.New("membership required")

// MembershipChecker reports whether成长会员 is active.
type MembershipChecker interface {
	IsActive(ctx context.Context, userID uuid.UUID) (bool, error)
}

// Service serves 探索测试.
type Service struct {
	Repo       *repository.ScaleRepo
	Profiles   *repository.ProfileRepo
	Membership MembershipChecker
}

// List returns published scales.
func (s *Service) List(ctx context.Context) ([]repository.ScaleListItem, error) {
	return s.Repo.ListPublished(ctx)
}

// Get returns scale detail; bank slugs served from curated embed; mbti-full may be locked.
func (s *Service) Get(ctx context.Context, userID uuid.UUID, slug string) (*repository.ScaleDetail, error) {
	if bank, err := scalebank.Get(slug); err == nil {
		if _, err := s.Repo.EnsurePublished(ctx, bank.Slug, bank.Title, bank.Description); err != nil {
			return nil, errors.New("scale not found")
		}
		d := &repository.ScaleDetail{
			Slug: bank.Slug, Title: bank.Title, Description: bank.Description, Access: "free",
		}
		for i, q := range bank.Questions {
			body, _ := json.Marshal(map[string]any{
				"prompt": q.Prompt, "options": q.Options,
			})
			d.Questions = append(d.Questions, repository.ScaleQuestion{
				ID: scalebank.QuestionID(slug, i), Sort: i + 1, Body: body,
			})
		}
		return d, nil
	}
	d, err := s.Repo.GetBySlug(ctx, slug)
	if err != nil {
		return nil, errors.New("scale not found")
	}
	if slug == "mbti-full" {
		d.Access = "membership"
		ok := false
		if s.Membership != nil && userID != uuid.Nil {
			ok, _ = s.Membership.IsActive(ctx, userID)
		}
		if !ok {
			d.Locked = true
			d.Questions = nil
		}
	} else {
		d.Access = "free"
	}
	return d, nil
}

// SubmitInput answers map question_id -> option key.
type SubmitInput struct {
	ProfileID uuid.UUID
	Answers   map[string]string
}

// SubmitResult is exploration result.
type SubmitResult struct {
	ID     uuid.UUID              `json:"id"`
	Result map[string]interface{} `json:"result"`
}

// Submit scores answers and stores result.
func (s *Service) Submit(ctx context.Context, userID uuid.UUID, slug string, in SubmitInput) (*SubmitResult, error) {
	if _, err := s.Profiles.GetForUser(ctx, userID, in.ProfileID); err != nil {
		return nil, errors.New("profile not found")
	}
	if slug == "mbti-full" {
		ok := false
		if s.Membership != nil {
			ok, _ = s.Membership.IsActive(ctx, userID)
		}
		if !ok {
			return nil, ErrMembershipRequired
		}
	}

	var result map[string]interface{}
	var scaleID uuid.UUID

	if bank, err := scalebank.Get(slug); err == nil {
		scaleID, err = s.Repo.EnsurePublished(ctx, bank.Slug, bank.Title, bank.Description)
		if err != nil {
			return nil, errors.New("scale not found")
		}
		key, label, _, _ := scalebank.ScoreSum(in.Answers, bank.QuestionCount)
		result = sc.BuildResult(slug, key, label)
		result["disclaimer"] = bank.Disclaimer
	} else {
		detail, err := s.Repo.GetBySlug(ctx, slug)
		if err != nil {
			return nil, errors.New("scale not found")
		}
		scaleID, err = s.Repo.ScaleIDBySlug(ctx, slug)
		if err != nil {
			return nil, errors.New("scale not found")
		}
		if slug == "mbti-lite" || slug == "mbti-full" {
			meta := map[string]sc.JungianQuestionMeta{}
			for _, q := range detail.Questions {
				meta[q.ID.String()] = sc.ParseJungianMeta(q.Body)
			}
			perDim := 8
			if slug == "mbti-full" {
				perDim = 15
			}
			code, _, pct := sc.ScoreJungian(in.Answers, meta, perDim)
			result = sc.BuildJungianResult(code, pct)
		} else {
			labels, _, _ := labelsForSlug(slug)
			key, label := sc.ScoreMajority(in.Answers, labels, "平衡探索型")
			result = sc.BuildResult(slug, key, label)
		}
	}
	ansJSON, _ := json.Marshal(in.Answers)
	resJSON, _ := json.Marshal(result)
	id, err := s.Repo.SaveResult(ctx, userID, scaleID, in.ProfileID, ansJSON, resJSON)
	if err != nil {
		return nil, err
	}
	return &SubmitResult{ID: id, Result: result}, nil
}

// LatestResult returns the newest stored result for this user + slug.
func (s *Service) LatestResult(ctx context.Context, userID uuid.UUID, slug string) (*SubmitResult, error) {
	if scalebank.Has(slug) {
		bank, err := scalebank.Get(slug)
		if err != nil {
			return nil, errors.New("scale not found")
		}
		if _, err := s.Repo.EnsurePublished(ctx, bank.Slug, bank.Title, bank.Description); err != nil {
			return nil, errors.New("scale not found")
		}
	} else if _, err := s.Repo.ScaleIDBySlug(ctx, slug); err != nil {
		return nil, errors.New("scale not found")
	}
	row, err := s.Repo.LatestResult(ctx, userID, slug)
	if err != nil {
		return nil, err
	}
	var result map[string]interface{}
	if err := json.Unmarshal(row.Result, &result); err != nil {
		return nil, errors.New("invalid result")
	}
	return &SubmitResult{ID: row.ID, Result: result}, nil
}

func labelsForSlug(slug string) (labels map[string]string, sharePrefix, summary string) {
	switch slug {
	case "emotion-pattern":
		return sc.EmotionLabels(),
			"我的情感模式：",
			"这是你当前情绪调节偏好的探索结果，可用于自我了解与日常调整，不是固定标签。"
	case "enneagram-lite":
		return map[string]string{"A": "尽责驱动型", "B": "联结驱动型", "C": "独立驱动型"},
			"我的动机模式：", "内在动机轻量探索，用于自我觉察。"
	case "bigfive-lite":
		return map[string]string{"O": "开放探索型", "C": "条理稳健型", "E": "主动外展型", "A": "温和协作型", "N": "细腻敏感型"},
			"我的性格五维：", "稳定特质速览，可随情境变化。"
	case "love-style":
		return map[string]string{"A": "稳定陪伴型", "B": "深度共鸣型", "C": "空间尊重型"},
			"我的亲密互动：", "亲密关系偏好探索，不是关系定论。"
	case "eq-lite":
		return map[string]string{"A": "觉察表达型", "B": "行动调节型", "C": "缓慢识别型"},
			"我的情绪觉察：", "情绪习惯探索，可用于日常调节。"
	case "stress-index":
		return map[string]string{"A": "节奏稳定型", "B": "波动调节型", "C": "高负荷需休息型"},
			"我的压力负荷：", "近期压力与恢复偏好，不是诊断。"
	case "career-interest":
		return map[string]string{"A": "创造表达型", "B": "助人支持型", "C": "分析解决型"},
			"我的职业兴趣：", "工作动力偏好探索，可作方向参考。"
	default:
		return sc.CommunicationLabels(),
			"我的沟通方式：",
			"这是你当前沟通偏好的探索结果，可用于自我了解与关系理解，不是固定标签。"
	}
}

// BankCatalog returns curated exploration bank tiles + categories.
func (s *Service) BankCatalog() (*scalebank.CatalogOut, error) {
	return scalebank.Catalog()
}

// BankCategory lists scales in a curated category.
func (s *Service) BankCategory(key string) (*scalebank.CategoryCard, []scalebank.ScaleListItem, error) {
	return scalebank.CategoryScales(key)
}