// Package outlook synthesizes daily/weekly/monthly/yearly/lifetime scores and transits.
package outlook

import (
	"fmt"
	"math"
	"time"

	"github.com/yuxingu/digital-psychology/apps/api/internal/star/natal"
)

// Period is one fortune block.
type Period struct {
	Key     string         `json:"key"`
	Title   string         `json:"title"`
	Score   int            `json:"score"`
	Label   string         `json:"label"`
	Dims    map[string]int `json:"dims"`
	Tip     string         `json:"tip"`
	Lucky   string         `json:"lucky"`
	Caution string         `json:"caution"`
	Focus   string         `json:"focus"`
}

// Transit is a simplified day transit tip relative to natal.
type Transit struct {
	Key    string `json:"key"`
	Title  string `json:"title"`
	Aspect string `json:"aspect"`
	Tip    string `json:"tip"`
}

// Bundle holds all periods plus lifetime and transits.
type Bundle struct {
	Daily    Period    `json:"daily"`
	Weekly   Period    `json:"weekly"`
	Monthly  Period    `json:"monthly"`
	Yearly   Period    `json:"yearly"`
	Lifetime Period    `json:"lifetime"`
	Transits []Transit `json:"transits"`
}

// Build returns fortune for natal chart as of asOf (date matters).
func Build(chart natal.Chart, asOf time.Time) Bundle {
	if asOf.IsZero() {
		asOf = time.Now()
	}
	sun := chart.Sun.Lon
	moon := chart.Moon.Lon
	daySeed := asOf.Year()*1000 + asOf.YearDay() + int(sun) + int(moon)

	daily := period("daily", "今日运势", daySeed, sun, moon, chart,
		[]string{"行动", "沟通", "情绪", "财运", "桃花"},
		[]string{
			fmt.Sprintf("发挥太阳「%s」的主动性，先完成一件小事。", chart.Sun.Sign),
			fmt.Sprintf("照顾月亮「%s」的情绪需要，给自己缓冲。", chart.Moon.Sign),
			"适合推进沟通：先复述再提方案。",
			"宜整理待办与开销，给节奏一点秩序。",
			"轻社交或独处充电均可，按电量选择。",
		})

	weekSeed := asOf.Year()*100 + isoWeek(asOf) + int(sun)/3
	weekly := period("weekly", "本周运势", weekSeed, sun, moon, chart,
		[]string{"事业", "关系", "学习", "休息", "决策"},
		[]string{
			"本周适合定一个可交付的小目标并公开承诺。",
			"关系上主动约一次轻松同步，不谈对错。",
			"学习/复盘：把灵感写成三条行动。",
			"安排半日空档恢复精力。",
			"重大决定用「可逆/不可逆」分类后再选速度。",
		})

	monthSeed := asOf.Year()*12 + int(asOf.Month()) + int(moon)/5
	monthly := period("monthly", "本月运势", monthSeed, sun, moon, chart,
		[]string{"感情", "事业", "财务", "健康节奏", "人际"},
		[]string{
			fmt.Sprintf("本月主题贴近「%s」：把热情落成节奏。", chart.Sun.Sign),
			"感情上说清需要，比猜测更有效。",
			"财务宜做一次月度复盘，砍掉低价值开销。",
			"作息与运动选可持续的小剂量。",
			"拓展一个人际弱连接，可能带来信息增益。",
		})

	yearSeed := asOf.Year() + int(sun) + int(chart.Rise.Lon)/10
	yearly := period("yearly", "今年运势", yearSeed, sun, moon, chart,
		[]string{"成长主线", "关系课题", "事业方向", "财富节奏", "身心"},
		[]string{
			fmt.Sprintf("今年宜强化太阳「%s」优势，并补月亮「%s」的安全感建设。", chart.Sun.Sign, chart.Moon.Sign),
			"关系课题：边界与亲密并重，写成说明书。",
			"事业上选择能看到里程碑的路径。",
			"财富：先稳现金流，再谈进取配置。",
			"身心：季度体检式复盘情绪与睡眠。",
		})

	life := lifetime(chart)
	tr := transits(chart, asOf)

	return Bundle{
		Daily: daily, Weekly: weekly, Monthly: monthly, Yearly: yearly,
		Lifetime: life, Transits: tr,
	}
}

func lifetime(chart natal.Chart) Period {
	sat := bodyLon(chart, "saturn")
	seed := int(chart.Sun.Lon) + int(sat)/2 + int(chart.Moon.Lon)/3
	score := 62 + seed%28
	stages := []string{
		fmt.Sprintf("成长主线贴近太阳「%s」：用可见行动定义自我。", chart.Sun.Sign),
		fmt.Sprintf("情感底色来自月亮「%s」：安全感与表达节奏需要长期经营。", chart.Moon.Sign),
		fmt.Sprintf("对外姿态偏上升「%s」：第一印象可以主动校准。", chart.Rise.Sign),
	}
	tip := stages[seed%len(stages)] + " 人生阶段不必一次做完，按十年课题拆解更稳。"
	return Period{
		Key: "lifetime", Title: "一生运势摘要", Score: score, Label: scoreLabel(score),
		Dims: map[string]int{
			"love": 50 + seed%40, "career": 52 + (seed*3)%40,
			"money": 48 + (seed*5)%42, "mood": 55 + (seed*7)%35,
		},
		Tip: tip, Focus: "人生阶段",
		Lucky:   "长期复盘 · 边界清晰",
		Caution: "避免把阶段标签当成宿命；可调整节奏与选择。",
	}
}

func transits(chart natal.Chart, asOf time.Time) []Transit {
	// Approximate "transit" sun/moon using same ephemeris at asOf noon CST.
	loc := time.FixedZone("CST", 8*3600)
	local := time.Date(asOf.Year(), asOf.Month(), asOf.Day(), 12, 0, 0, 0, loc)
	tChart, err := natal.Compute(local, strPtr("12:00"), placePtr(chart.PlaceLabel))
	if err != nil {
		return nil
	}
	tSun, tMoon := tChart.Sun.Lon, tChart.Moon.Lon

	out := []Transit{}
	out = append(out, transitHit("transit_sun_natal_sun", "行运太阳×本命太阳", tSun, chart.Sun.Lon,
		"适合主动推进与自我表达相关的事。",
		"宜复盘目标，不急着扩张战线。",
		"注意沟通语气，先对齐再行动。"))
	out = append(out, transitHit("transit_moon_natal_moon", "行运月亮×本命月亮", tMoon, chart.Moon.Lon,
		"情绪敏感日，给自己更多缓冲。",
		"适合温柔连结与休息充电。",
		"避免情绪化决策，先写下来再说。"))
	out = append(out, transitHit("transit_sun_natal_moon", "行运太阳×本命月亮", tSun, chart.Moon.Lon,
		"外在节奏触动内在需求，适合说清感受。",
		"工作与情绪平衡日，留一点空白。",
		"别硬撑社交，按电量选择场合。"))
	return out
}

func transitHit(key, title string, a, b float64, conj, soft, hard string) Transit {
	diff := natal.AngleDiff(a, b)
	aspect, tip := "弱互动", "节奏平常，按计划推进即可。"
	switch {
	case near(diff, 0, 8):
		aspect, tip = "合相", conj
	case near(diff, 60, 6) || near(diff, 120, 7):
		aspect, tip = "和谐相位", soft
	case near(diff, 90, 7) || near(diff, 180, 8):
		aspect, tip = "张力相位", hard
	}
	return Transit{Key: key, Title: title, Aspect: aspect, Tip: tip}
}

func near(diff, target, orb float64) bool {
	return math.Abs(diff-target) <= orb
}

func bodyLon(c natal.Chart, key string) float64 {
	for _, p := range c.Planets {
		if p.Key == key {
			return p.Lon
		}
	}
	return 0
}

func strPtr(s string) *string { return &s }
func placePtr(s string) *string {
	if s == "" || s == "默认（未填出生地）" {
		return nil
	}
	return &s
}

func period(key, title string, seed int, sun, moon float64, chart natal.Chart, focuses, tips []string) Period {
	score := 55 + (seed*7+int(sun)+int(moon))%41 // 55–95
	love := 50 + (seed*3+int(moon))%46
	career := 50 + (seed*5+int(sun))%46
	money := 48 + (seed*11+int(chart.Rise.Lon))%47
	mood := 52 + (seed*13+int(moon)/2)%45
	i := seed % len(tips)
	return Period{
		Key: key, Title: title, Score: score, Label: scoreLabel(score),
		Dims: map[string]int{
			"love": love, "career": career, "money": money, "mood": mood,
		},
		Tip: tips[i], Focus: focuses[i%len(focuses)],
		Lucky:   luckyFrom(seed),
		Caution: cautionFrom(seed, chart),
	}
}

func scoreLabel(s int) string {
	switch {
	case s >= 85:
		return "大吉"
	case s >= 75:
		return "吉"
	case s >= 65:
		return "中平偏吉"
	case s >= 55:
		return "平稳"
	default:
		return "需谨慎"
	}
}

func luckyFrom(seed int) string {
	colors := []string{"红色", "金色", "蓝色", "绿色", "紫色", "白色"}
	nums := []string{"3", "6", "7", "8", "9"}
	return colors[seed%len(colors)] + " · 数字 " + nums[seed%len(nums)]
}

func cautionFrom(seed int, chart natal.Chart) string {
	cautions := []string{
		"避免冲动承诺，尤其财务相关。",
		fmt.Sprintf("「%s」能量过强时易急躁，先深呼吸再回复。", chart.Sun.Sign),
		"少开多线任务，完成比完美重要。",
		"情绪波动时先写下来，再找人聊。",
	}
	return cautions[seed%len(cautions)]
}

func isoWeek(t time.Time) int {
	_, w := t.ISOWeek()
	return w
}

// AsMap for JSON embedding.
func (b Bundle) AsMap() map[string]any {
	tr := make([]map[string]any, 0, len(b.Transits))
	for _, t := range b.Transits {
		tr = append(tr, map[string]any{
			"key": t.Key, "title": t.Title, "aspect": t.Aspect, "tip": t.Tip,
		})
	}
	return map[string]any{
		"daily": periodMap(b.Daily), "weekly": periodMap(b.Weekly),
		"monthly": periodMap(b.Monthly), "yearly": periodMap(b.Yearly),
		"lifetime": periodMap(b.Lifetime), "transits": tr,
	}
}

func periodMap(p Period) map[string]any {
	return map[string]any{
		"key": p.Key, "title": p.Title, "score": p.Score, "label": p.Label,
		"dims": p.Dims, "tip": p.Tip, "lucky": p.Lucky, "caution": p.Caution, "focus": p.Focus,
	}
}