package web

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
	"strings"

	"daili/internal/domain"
	"daili/internal/store"
)

type screenDay struct {
	Date    string
	Day     int
	InMonth bool
	IsToday bool
	IsPast  bool
	Count   int
	Done    int
	Urgent  int
	Heat    int
	// Strip 打手色竖条（去重）
	Strip []string
}

type screenTask struct {
	TaskRow
}

type screenData struct {
	Stats        *store.Stats
	MonthTitle   string
	Year, Month  int
	Weeks        [][]screenDay
	Weekdays     []string
	Top          []SubView
	DueToday     []SubView
	TodayList    []screenTask
	Recent       []store.Adjustment
	TodayTasks   int
	TodayDone    int
	TodayUrgent  int
	Refresh      int
	Version      string
	AssetVersion string

	HeatMode    string // task = 每日待完成；due = 到期
	Tag         string
	HeatTotal   int
	Tabs        []PkgTab
	PkgID       int64
	HasTabs     bool
	FilterQuery string
	Theme       string
}

// screenCalSubs 读取大屏日历区间内的订阅，并带上暂停/打卡/加急。
func (s *Server) screenCalSubs(from, to string, pkgID int64, tag string) ([]calSub, map[int64]map[string]store.Checkin, map[int64]map[string]bool, error) {
	subs, pauses, checkins, urgent, err := s.loadCalendarSubs(from, to, pkgID, tag)
	if err != nil {
		return nil, nil, nil, err
	}
	today := domain.Today()
	warn := s.warnDays()
	list := make([]calSub, 0, len(subs))
	for _, sub := range subs {
		cs := calSub{sub: sub, pauses: pauses[sub.ID], checkins: checkins[sub.ID], eval: sub.Eval(today, warn)}
		if sub.EndDate != "" {
			cs.hasEnd = true
			cs.end = domain.ParseDateOr(sub.EndDate, today)
		}
		list = append(list, cs)
	}
	return list, checkins, urgent, nil
}

func (s *Server) handleScreen(w http.ResponseWriter, r *http.Request) {
	today := domain.Today()
	warn := s.warnDays()
	pkgID := int64(s.queryInt(r, "pkg", 0))
	tag := strings.TrimSpace(r.URL.Query().Get("tag"))
	heatMode := r.URL.Query().Get("heat")
	if heatMode != "due" {
		heatMode = "task"
	}

	stats, err := s.db.ScreenStats(today, warn)
	if err != nil {
		http.Error(w, "读取大屏数据失败", http.StatusInternalServerError)
		return
	}
	data := &screenData{
		Stats:        stats,
		MonthTitle:   fmt.Sprintf("%d 年 %d 月", today.Year(), int(today.Month())),
		Year:         today.Year(),
		Month:        int(today.Month()),
		Weekdays:     []string{"一", "二", "三", "四", "五", "六", "日"},
		Top:          subViews(stats.Top, today, warn),
		Refresh:      s.screenRefresh(),
		Version:      s.cfg.Version,
		AssetVersion: s.assetVersion,
		HeatMode:     heatMode,
		PkgID:        pkgID,
		Tag:          tag,
		FilterQuery:  "pkg=" + itoa(pkgID),
	}

	// 今日到期（可按套餐过滤）
	dueToday := []store.Subscription{}
	for _, sub := range stats.DueTodaySubs {
		if pkgID > 0 && sub.PackageID != pkgID {
			continue
		}
		dueToday = append(dueToday, sub)
	}
	data.DueToday = subViews(dueToday, today, warn)

	// 本月热力：默认统计“每日待完成的单子”，可切换到“到期”
	monthStart := domain.MonthStart(today.Year(), today.Month())
	monthEnd := domain.MonthEnd(today.Year(), today.Month())
	gridStart := domain.AddDays(monthStart, -domain.WeekdayIndex(monthStart))
	weeks := (domain.WeekdayIndex(monthStart) + monthEnd.Day() + 6) / 7
	gridEnd := domain.AddDays(gridStart, weeks*7-1)

	list, checkins, urgent, err := s.screenCalSubs(domain.Date(gridStart), domain.Date(gridEnd), pkgID, tag)
	if err != nil {
		http.Error(w, "读取大屏日历失败", http.StatusInternalServerError)
		return
	}

	for wi := 0; wi < weeks; wi++ {
		week := make([]screenDay, 0, 7)
		for di := 0; di < 7; di++ {
			d := domain.AddDays(gridStart, wi*7+di)
			ds := domain.Date(d)
			count, doneN, urgentN := 0, 0, 0
			strip := []string{}
			seenColor := map[string]bool{}
			for _, cs := range list {
				if heatMode == "due" {
					if cs.sub.EndDate == ds {
						count++
					}
					continue
				}
				// 通行证 / 深渊是整段型，不计入「每日待完成」热力
				if cs.isBlock() {
					continue
				}
				if !cs.covers(ds) {
					continue
				}
				ci, has := checkins[cs.sub.ID][ds]
				if has && (ci.Status == "done" || ci.Status == "skipped") {
					doneN++
					continue // “待完成”热力只统计还没处理的
				}
				count++
				if urgent[cs.sub.ID][ds] {
					urgentN++
				}
				color := cs.sub.AssigneeColor
				if color == "" {
					color = "#8A8F98"
				}
				if !seenColor[color] {
					seenColor[color] = true
					strip = append(strip, color)
				}
			}
			if d.Month() == today.Month() {
				data.HeatTotal += count
			}
			week = append(week, screenDay{
				Date:    ds,
				Day:     d.Day(),
				InMonth: d.Month() == today.Month(),
				IsToday: ds == domain.Date(today),
				IsPast:  d.Before(today),
				Count:   count + doneN,
				Done:    doneN,
				Urgent:  urgentN,
				Heat:    heatLevel(count),
				Strip:   strip,
			})
		}
		data.Weeks = append(data.Weeks, week)
	}

	// 今日待打（加急置顶）
	rows, err := s.pendingTasks(domain.Date(today), nil, pkgID, tag)
	if err == nil {
		for _, row := range rows {
			if row.Done || row.Skipped {
				continue
			}
			data.TodayList = append(data.TodayList, screenTask{TaskRow: row})
			if row.Urgent {
				data.TodayUrgent++
			}
		}
	}
	data.TodayTasks = len(data.TodayList)
	for _, row := range rows {
		if row.Done {
			data.TodayDone++
		}
	}

	// 最近追加（底部细条）
	if adj, err := s.db.RecentAdjustments(6); err == nil {
		data.Recent = adj
	}

	// 页签：按标签合并 + 独立显示另开；通行证/深渊不计每日热力，不放大屏页签
	pkgs, _ := s.db.ListPackages(true)
	screenPkgs := make([]store.Package, 0, len(pkgs))
	for _, p := range pkgs {
		if p.Season || p.Abyss {
			continue
		}
		screenPkgs = append(screenPkgs, p)
	}
	data.Tabs, data.HasTabs = buildCalendarTabs(screenPkgs, nil, 0)
	for i := range data.Tabs {
		t := &data.Tabs[i]
		href := "/screen?heat=" + heatMode
		if t.Tag != "" {
			href += "&tag=" + url.QueryEscape(t.Tag)
			t.Active = t.Tag == tag
		} else if t.ID > 0 {
			href += "&pkg=" + itoa(t.ID)
			t.Active = t.ID == pkgID
		} else {
			t.Active = tag == "" && pkgID == 0
		}
		t.Href = href
	}

	if tag != "" {
		data.FilterQuery = "tag=" + url.QueryEscape(tag)
	}
	data.Theme = themeFromRequest(r)
	p := s.newPage(r, "大屏", "screen")
	p.Theme = data.Theme
	p.D = data
	s.render(w, r, "screen", p)
}

// handleScreenDay 返回某天的待办明细，供大屏悬停浮层使用。
func (s *Server) handleScreenDay(w http.ResponseWriter, r *http.Request) {
	date := r.URL.Query().Get("date")
	if _, err := domain.ParseDate(date); err != nil {
		http.Error(w, "日期不正确", http.StatusBadRequest)
		return
	}
	pkgID := int64(s.queryInt(r, "pkg", 0))
	rows, err := s.pendingTasks(date, nil, pkgID, strings.TrimSpace(r.URL.Query().Get("tag")))
	if err != nil {
		http.Error(w, "读取失败", http.StatusInternalServerError)
		return
	}
	type item struct {
		Tail   string `json:"tail"`
		Name   string `json:"name"`
		Pkg    string `json:"pkg"`
		Color  string `json:"color"`
		Remain string `json:"remain"`
		Urgent bool   `json:"urgent"`
		Done   bool   `json:"done"`
		Who    string `json:"who"`
		WhoCol string `json:"who_color"`
	}
	out := struct {
		Date   string `json:"date"`
		Total  int    `json:"total"`
		Done   int    `json:"done"`
		Urgent int    `json:"urgent"`
		More   int    `json:"more"`
		Items  []item `json:"items"`
	}{Date: date}

	const limit = 60
	for _, row := range rows {
		out.Total++
		if row.Done || row.Skipped {
			out.Done++
		}
		if row.Urgent {
			out.Urgent++
		}
		if len(out.Items) >= limit {
			out.More++
			continue
		}
		out.Items = append(out.Items, item{
			Tail:   row.CustomerTail,
			Name:   row.CustomerName,
			Pkg:    row.PackageName,
			Color:  row.PackageColor,
			Remain: row.RemainText,
			Urgent: row.Urgent,
			Done:   row.Done || row.Skipped,
			Who:    row.AssigneeLabel(),
			WhoCol: row.AssigneeHex(),
		})
	}
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.Header().Set("Cache-Control", "no-store")
	_ = json.NewEncoder(w).Encode(out)
}