package grils

import (
	"fmt"
	"log"
	"net/http"
	"regexp"
	"strconv"
    "time"
	"strings"

	"fagott.pw/charakterin"
	"fagott.pw/grilist/frontend"
	"fagott.pw/grilist/grilist"
    "fagott.pw/grilist/cache"

	"github.com/julienschmidt/httprouter"
)

type CachedGril struct {
    Created time.Time
    Gril *Gril
}

var (
	pgArrayReg = regexp.MustCompile(`(((?P<value>(([^",\\{}\s(NULL)])+|"([^"\\]|\\"|\\\\)*")))(,)?)`)
	pgValueIdx int
)

func findIdx() {
	for i, subexp := range pgArrayReg.SubexpNames() {
		if subexp == "value" {
			pgValueIdx = i
			break
		}
	}
}

type GrilsModule struct {
	g *grilist.Grilist
    c *cache.Cache
}

func (m *GrilsModule) Name() string {
	return "Grils"
}

func (m *GrilsModule) Init(g *grilist.Grilist) {
	findIdx()
	m.g = g
	m.g.Router.GET("/gril/:id", m.viewGril)
	m.g.Router.GET("/gril/:id/*rest", m.viewGril)
    
    m.c = cache.New()
}

func (m *GrilsModule) getGrils(whereClause string, params ...interface{}) ([]*Gril, error) {
	var grils []*Gril

	rows, err := m.g.DB.Query(fmt.Sprintf(`SELECT id, kanji_name, romaji_name, other_names, updated_at, age, birthday, tags FROM grilist.grils_flattened WHERE %s`, whereClause), params...)
	if err != nil {
		return nil, err
	}

	defer rows.Close()
	for rows.Next() {
		gril := &Gril{}
		var tags []byte
		var otherNames []byte
		err = rows.Scan(&gril.ID, &gril.KanjiName, &gril.RomajiName, &otherNames, &gril.UpdatedAt, &gril.Age, &gril.Birthday, &tags)
		if err != nil {
			log.Println(gril.ID)
			log.Println("error scanning in getGrils:", err)
			continue
		}

		gril.Tags = pgArray(tags)
		gril.OtherNames = pgArray(otherNames)

		grils = append(grils, gril)
	}

	return grils, nil
}

func (m *GrilsModule) GetListsOfGril(gril *Gril) error {
	rows, err := m.g.DB.Query(`SELECT list_id FROM grilist.lists_grils WHERE gril_id = $1`, gril.ID)
	if err != nil {
		return err
	}

	defer rows.Close()
	for rows.Next() {
		var listID int
		if err := rows.Scan(&listID); err != nil {
			log.Println(err)
			continue
		}

		gril.Lists = append(gril.Lists, listID)
	}

	return nil
}

func (m *GrilsModule) ProvideDashboardData(user *charakterin.User) []grilist.DashboardCategory {
	var categories []grilist.DashboardCategory

	t1 := time.Now()
	rows, err := m.g.DB.Query(`SELECT id FROM grilist.grils ORDER BY updated_at DESC LIMIT 5`)
	if err != nil {
		log.Println(err)
		return categories
	}
	defer rows.Close()
	log.Printf("get_newest_grils: %dms", time.Since(t1).Nanoseconds()/1000000)

	cat := grilist.DashboardCategory{
		Title: "Neue Grils",
	}

	for rows.Next() {
		var id int
		if err := rows.Scan(&id); err != nil {
			log.Println(err)
			continue
		}

		t2 := time.Now()
		gril, err := m.FromID(id)
		if err != nil {
			log.Println(err)
			continue
		}
		log.Printf("get_gril_from_id_in_newest_grils: %dms", time.Since(t2).Nanoseconds()/1000000)

		cat.Cards = append(cat.Cards, frontend.Card{
			Title:       gril.RomajiName,
			Description: gril.KanjiName,
			Size:        "medium",
			Actions: []frontend.Action{
				frontend.Action{
					Name: "anguckieren",
					Link: "/gril/" + gril.Slug(),
				},
			},
		})
	}
	categories = append(categories, cat)
	log.Printf("get_newest_grils_overall: %dms", time.Since(t1).Nanoseconds()/1000000)
	return categories
}

func (m *GrilsModule) FromID(id int) (*Gril, error) {
    if g, ok := m.c.Get(id); ok {
        return g.(*Gril), nil
    }
    
	gril := &Gril{
		ID: id,
	}
	var tags []byte
	var otherNames []byte
	err := m.g.DB.QueryRow(`SELECT kanji_name, romaji_name, other_names, updated_at, age, birthday, tags FROM grilist.grils_flattened WHERE id = $1`, id).Scan(&gril.KanjiName, &gril.RomajiName, &otherNames, &gril.UpdatedAt, &gril.Age, &gril.Birthday, &tags)

	gril.Tags = pgArray(tags)
	gril.OtherNames = pgArray(otherNames)
	if err != nil {
		return nil, err
	}
    m.c.Insert(id, gril)
	return gril, nil
}

func (m *GrilsModule) FromIDs(ids []int) ([]*Gril, error) {
	if len(ids) == 0 {
		return make([]*Gril, 0), nil
	}

	idList := "("
	first := true
	for _, v := range ids {
		if first {
			first = false
		} else {
			idList += ","
		}
		idList += strconv.Itoa(v)
	}
	idList += ")"
	grils, err := m.getGrils("id IN " + idList)
	return grils, err
}

func (m *GrilsModule) viewGril(w http.ResponseWriter, r *http.Request, p httprouter.Params) {
	user, _ := m.g.Charakterin.GetUserFromRequest(r)
	sid := p.ByName("id")

	id, err := strconv.Atoi(sid)
	if err != nil {
		http.Redirect(w, r, "/", 302)
		return
	}

	gril, err := m.FromID(id)
	if err != nil {
		http.Redirect(w, r, "/", 302)
		return
	}

	if err := m.GetListsOfGril(gril); err != nil {
		log.Println(err)
	}

	data := m.g.Renderer.DefaultData()
	data["user"] = user
	data["gril"] = gril

	// ähnliche grils holen
	rows, err := m.g.DB.Query(`SELECT gril_id FROM (
	SELECT DISTINCT gril_id FROM gril_appearance WHERE appearance_id IN (SELECT appearance_id FROM gril_appearance WHERE gril_id = $1)
	) as t
    ORDER BY RANDOM()
    LIMIT 4;`, id)
	if err != nil {
		log.Println("could not get similar grils:", err)
		http.Error(w, "500", http.StatusInternalServerError)
		return
	}

	defer rows.Close()
	var similar []*Gril
	for rows.Next() {
		var id int
		if err := rows.Scan(&id); err != nil {
			log.Println("error scanning for similar gril:", err)
			continue
		}

		g, err := m.FromID(id)
		if err != nil {
			log.Println("invalid similar gril:", err)
			continue
		}
		similar = append(similar, g)
	}
	data["SimilarGrils"] = similar

	m.g.Renderer.RenderPage("gril", w, data)
}

func pgArray(array []byte) []string {
	var results []string
	matches := pgArrayReg.FindAllStringSubmatch(string(array), -1)
	for _, match := range matches {
		s := match[pgValueIdx]
		s = strings.Trim(s, "\"")
		results = append(results, s)
	}
	return results
}

func New() *GrilsModule {
	return &GrilsModule{}
}