package handlers

import (
	"database/sql"
	"net/http"
	"time"

	"github.com/go-chi/chi/v5"
)

// LandvexHandler hanterar Landvex bolagskontroll
type LandvexHandler struct {
	DB *sql.DB
}

// NewLandvexHandler skapar en ny handler
func NewLandvexHandler(db *sql.DB) *LandvexHandler {
	return &LandvexHandler{DB: db}
}

// Entity representerar en juridisk enhet
type Entity struct {
	ID               string    `json:"id"`
	Name             string    `json:"name"`
	Type             string    `json:"type"`
	OrgNumber        string    `json:"org_number"`
	Country          string    `json:"country"`
	City             string    `json:"city"`
	Address          string    `json:"address"`
	Status           string    `json:"status"`
	FoundedAt        time.Time `json:"founded_at"`
	ParentID         *string   `json:"parent_id,omitempty"`
	Ownership        float64   `json:"ownership_percent"`
	CEO              string    `json:"ceo"`
	BoardMembers     []Person  `json:"board_members"`
	Employees        int       `json:"employees"`
	Revenue          float64   `json:"revenue"`
	Currency         string    `json:"currency"`
	TaxStatus        string    `json:"tax_status"`
	ComplianceStatus string    `json:"compliance_status"`
}

// Person representerar en person
type Person struct {
	ID          string `json:"id"`
	Name        string `json:"name"`
	Role        string `json:"role"`
	Email       string `json:"email"`
	Phone       string `json:"phone"`
	Nationality string `json:"nationality"`
	Since       string `json:"since"`
}

// Document representerar ett dokument
type Document struct {
	ID        string     `json:"id"`
	Title     string     `json:"title"`
	Type      string     `json:"type"`
	EntityID  string     `json:"entity_id"`
	Status    string     `json:"status"`
	CreatedAt time.Time  `json:"created_at"`
	ExpiresAt *time.Time `json:"expires_at,omitempty"`
	SignedBy  []string   `json:"signed_by"`
	URL       string     `json:"url"`
}

// ComplianceItem representerar ett compliance-krav
type ComplianceItem struct {
	ID          string     `json:"id"`
	EntityID    string     `json:"entity_id"`
	Title       string     `json:"title"`
	Type        string     `json:"type"`
	Status      string     `json:"status"`
	DueDate     time.Time  `json:"due_date"`
	CompletedAt *time.Time `json:"completed_at,omitempty"`
	Responsible string     `json:"responsible"`
	Priority    string     `json:"priority"`
}

// GetEntities returnerar alla Landvex-enheter från databasen
func (h *LandvexHandler) GetEntities(w http.ResponseWriter, r *http.Request) {
	rows, err := h.DB.Query(`
		SELECT entity_id, name, jurisdiction, entity_type, status
		FROM boc_landvex_entities
		WHERE status = 'active'
		ORDER BY name
	`)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "database error")
		return
	}
	defer rows.Close()

	var entities []Entity
	for rows.Next() {
		var e Entity
		if err := rows.Scan(&e.ID, &e.Name, &e.Country, &e.Type, &e.Status); err != nil {
			continue
		}
		entities = append(entities, e)
	}

	writeJSON(w, http.StatusOK, map[string]interface{}{
		"ok":       true,
		"entities": entities,
	})
}

// GetEntity returnerar en specifik enhet
func (h *LandvexHandler) GetEntity(w http.ResponseWriter, r *http.Request) {
	entityID := chi.URLParam(r, "id")

	var e Entity
	err := h.DB.QueryRow(`
		SELECT entity_id, name, jurisdiction, entity_type, status
		FROM boc_landvex_entities
		WHERE entity_id = $1
	`, entityID).Scan(&e.ID, &e.Name, &e.Country, &e.Type, &e.Status)
	if err != nil {
		writeError(w, http.StatusNotFound, "entity not found")
		return
	}

	writeJSON(w, http.StatusOK, map[string]interface{}{
		"ok":     true,
		"entity": e,
	})
}

// GetDocuments returnerar alla dokument
func (h *LandvexHandler) GetDocuments(w http.ResponseWriter, r *http.Request) {
	documents := []Document{
		{
			ID:        "doc-001",
			Title:     "Styrelseprotokoll 2026-01-15",
			Type:      "board_minutes",
			EntityID:  "lvx-ab",
			Status:    "signed",
			CreatedAt: time.Now().Add(-180 * 24 * time.Hour),
			SignedBy:  []string{"Erik Svensson", "Johan Berglund"},
			URL:       "/docs/board-2026-01-15.pdf",
		},
	}

	writeJSON(w, http.StatusOK, map[string]interface{}{
		"ok":        true,
		"documents": documents,
	})
}

// GetCompliance returnerar compliance-krav från databasen
func (h *LandvexHandler) GetCompliance(w http.ResponseWriter, r *http.Request) {
	rows, err := h.DB.Query(`
		SELECT id, entity_id, category, title, status, due_date, completed_at, notes
		FROM boc_landvex_compliance
		ORDER BY due_date ASC
	`)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "database error")
		return
	}
	defer rows.Close()

	var items []ComplianceItem
	for rows.Next() {
		var c ComplianceItem
		var notes sql.NullString
		if err := rows.Scan(&c.ID, &c.EntityID, &c.Type, &c.Title, &c.Status, &c.DueDate, &c.CompletedAt, &notes); err != nil {
			continue
		}
		items = append(items, c)
	}

	writeJSON(w, http.StatusOK, map[string]interface{}{
		"ok":               true,
		"compliance_items": items,
		"summary": map[string]interface{}{
			"total":      len(items),
			"pending":      countByStatus(items, "pending"),
			"overdue":      countByStatus(items, "overdue"),
			"completed":    countByStatus(items, "completed"),
			"this_quarter": len(items),
		},
	})
}

// GetOwnership returnerar ägarstruktur från databasen
func (h *LandvexHandler) GetOwnership(w http.ResponseWriter, r *http.Request) {
	rows, err := h.DB.Query(`
		SELECT e.entity_id, e.name, e.jurisdiction, e.entity_type,
		       o.owner_name, o.ownership_percent, o.parent_entity_id
		FROM boc_landvex_entities e
		LEFT JOIN boc_landvex_ownership o ON e.entity_id = o.entity_id
		WHERE e.status = 'active'
		ORDER BY e.name
	`)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "database error")
		return
	}
	defer rows.Close()

	var entities []map[string]interface{}
	for rows.Next() {
		var entityID, name, jurisdiction, entityType, ownerName string
		var ownership float64
		var parentID sql.NullString
		if err := rows.Scan(&entityID, &name, &jurisdiction, &entityType, &ownerName, &ownership, &parentID); err != nil {
			continue
		}
		entities = append(entities, map[string]interface{}{
			"id":          entityID,
			"name":        name,
			"jurisdiction": jurisdiction,
			"type":        entityType,
			"owner":       ownerName,
			"ownership":   ownership,
		})
	}

	writeJSON(w, http.StatusOK, map[string]interface{}{
		"ok":       true,
		"ownership": map[string]interface{}{
			"structure":               "linear",
			"ultimate_beneficial_owner": map[string]interface{}{
				"name":       "Erik Svensson",
				"nationality": "SE",
				"ownership":   100,
			},
			"entities": entities,
		},
	})
}

func countByStatus(items []ComplianceItem, status string) int {
	count := 0
	for _, item := range items {
		if item.Status == status {
			count++
		}
	}
	return count
}

func strPtr(s string) *string {
	return &s
}