package httpapi_test

import (
	"encoding/json"
	"io"
	"net/http"
	"strings"
	"testing"
)

// decodeRaw 解析 doRaw 返回的完整响应体（{ok,data} 信封）。
func decodeRaw[T any](t *testing.T, raw []byte) T {
	t.Helper()
	var env envelope
	if err := json.Unmarshal(raw, &env); err != nil {
		t.Fatalf("解析响应: %v (%s)", err, raw)
	}
	return decodeData[T](t, env)
}

// exportRulesYAML 取当前规则包（导出与导入共用同一序列化，保证往返可解析）。
func (e *testEnv) exportRulesYAML(t *testing.T, client *http.Client) string {
	t.Helper()
	resp, err := client.Get(e.server.URL + "/api/rules/export")
	if err != nil {
		t.Fatalf("导出规则包: %v", err)
	}
	defer func() { _ = resp.Body.Close() }()
	body, err := io.ReadAll(resp.Body)
	if err != nil || resp.StatusCode != http.StatusOK {
		t.Fatalf("导出规则包失败 status=%d err=%v", resp.StatusCode, err)
	}
	return string(body)
}

// publishTwoResults 录入两条成绩并发布，返回两条流水的分值（按单位）。
func (e *testEnv) publishTwoResults(t *testing.T, client *http.Client, ids seedIDs) {
	t.Helper()
	status, env2 := e.do(client, http.MethodPut, "/api/results/draft", map[string]any{
		"eventId":   ids.event,
		"requestId": "draft-rules-1",
		"results": []map[string]any{
			{"entryId": ids.entryA, "resultValue": 11.58, "resultText": "11.58", "unit": "s", "status": "ok"},
			{"entryId": ids.entryB, "resultValue": 11.92, "resultText": "11.92", "unit": "s", "status": "ok"},
		},
	}, true)
	if status != http.StatusOK || !env2.OK {
		t.Fatalf("保存草稿应 200，得到 %d %+v", status, env2.Error)
	}
	status, env2 = e.do(client, http.MethodPost, "/api/results/publish", map[string]any{
		"eventId":   ids.event,
		"requestId": "publish-rules-1",
	}, true)
	if status != http.StatusOK || !env2.OK {
		t.Fatalf("发布应 200，得到 %d %+v", status, env2.Error)
	}
}

// ledgerPointsByTeam 读取当前有效流水的「单位 → 分值」。
func (e *testEnv) ledgerPointsByTeam(t *testing.T) map[int64]float64 {
	t.Helper()
	rows, err := e.ev.Query(`SELECT team_id, points FROM score_ledger WHERE voided = 0 AND source_type = 'result'`)
	if err != nil {
		t.Fatalf("查询流水: %v", err)
	}
	defer func() { _ = rows.Close() }()
	out := map[int64]float64{}
	for rows.Next() {
		var team int64
		var points float64
		if err := rows.Scan(&team, &points); err != nil {
			t.Fatalf("扫描流水: %v", err)
		}
		out[team] = points
	}
	return out
}

// 规则导入后必须回写名次：分值一变，results.rank 也要跟着新规则重算（P0-5）。
func TestRulesImportRewritesRanks(t *testing.T) {
	env := newTestEnv(t)
	ids := env.seed(t)
	env.createUser("admin", "admin-pass", "admin")
	client, _ := env.client()
	env.login(client, "admin", "admin-pass")
	env.publishTwoResults(t, client, ids)

	// 模拟名次过期/写坏，导入规则包后应被重算覆盖。
	env.exec(t, `UPDATE results SET rank = 99 WHERE event_id = ?`, ids.event)

	pack := env.exportRulesYAML(t, client)
	status, raw := env.doRaw(client, http.MethodPost, "/api/rules/import", []byte(pack), "application/yaml", true)
	if status != http.StatusOK {
		t.Fatalf("导入规则包应 200，得到 %d %s", status, raw)
	}

	rows, err := env.ev.Query(`SELECT entry_id, rank FROM results WHERE event_id = ? ORDER BY entry_id`, ids.event)
	if err != nil {
		t.Fatalf("查询名次: %v", err)
	}
	defer func() { _ = rows.Close() }()
	ranks := map[int64]int64{}
	for rows.Next() {
		var entryID, rank int64
		if err := rows.Scan(&entryID, &rank); err != nil {
			t.Fatalf("扫描名次: %v", err)
		}
		ranks[entryID] = rank
	}
	if ranks[ids.entryA] != 1 || ranks[ids.entryB] != 2 {
		t.Fatalf("导入后名次应重算为 A=1 B=2，得到 %+v", ranks)
	}
}

// 预览与落地响应必须带上 compatible / affectedEventCount / recalculatedLedgerRows（P1-11）。
func TestRulesImportReturnsContractFields(t *testing.T) {
	env := newTestEnv(t)
	ids := env.seed(t)
	env.createUser("admin", "admin-pass", "admin")
	client, _ := env.client()
	env.login(client, "admin", "admin-pass")
	env.publishTwoResults(t, client, ids)

	// 把 M100 的计分通道换成团队模板：制造一个「影响 1 个小项」的差异。
	pack := env.exportRulesYAML(t, client)
	changed := strings.Replace(pack, "profile: individual_top6", "profile: team_top6", 1)
	if changed == pack {
		t.Fatalf("规则包里没有可替换的计分通道，导出内容:\n%s", pack)
	}

	// 只改模板分值：引用了该模板的小项同样算「被影响」。
	pointsChanged := strings.Replace(pack, "points: 10", "points: 11", 1)
	if pointsChanged == pack {
		t.Fatalf("规则包里没有可替换的分值，导出内容:\n%s", pack)
	}
	status, raw := env.doRaw(client, http.MethodPost, "/api/rules/import?preview=1", []byte(pointsChanged), "application/yaml", true)
	if status != http.StatusOK {
		t.Fatalf("预览应 200，得到 %d %s", status, raw)
	}
	pointsPreview := decodeRaw[map[string]any](t, raw)
	if count, _ := pointsPreview["affectedEventCount"].(float64); count != 1 {
		t.Fatalf("只改模板分值时 affectedEventCount 应为 1，得到 %+v", pointsPreview["affectedEventCount"])
	}

	status, raw = env.doRaw(client, http.MethodPost, "/api/rules/import?preview=1", []byte(changed), "application/yaml", true)
	if status != http.StatusOK {
		t.Fatalf("预览应 200，得到 %d %s", status, raw)
	}
	preview := decodeRaw[map[string]any](t, raw)
	if preview["compatible"] != true {
		t.Fatalf("预览 compatible 应为 true，得到 %+v", preview["compatible"])
	}
	if count, _ := preview["affectedEventCount"].(float64); count != 1 {
		t.Fatalf("预览 affectedEventCount 应为 1，得到 %+v", preview["affectedEventCount"])
	}
	if channels, _ := preview["channels"].([]any); len(channels) != 1 {
		t.Fatalf("预览 channels 应含 1 个小项，得到 %+v", preview["channels"])
	}

	status, raw = env.doRaw(client, http.MethodPost, "/api/rules/import", []byte(changed), "application/yaml", true)
	if status != http.StatusOK {
		t.Fatalf("导入应 200，得到 %d %s", status, raw)
	}
	applied := decodeRaw[map[string]any](t, raw)
	if applied["compatible"] != true {
		t.Fatalf("导入结果 compatible 应为 true，得到 %+v", applied["compatible"])
	}
	if count, _ := applied["affectedEventCount"].(float64); count != 1 {
		t.Fatalf("导入结果 affectedEventCount 应为 1，得到 %+v", applied["affectedEventCount"])
	}
	if rows, _ := applied["recalculatedLedgerRows"].(float64); rows != 2 {
		t.Fatalf("导入结果 recalculatedLedgerRows 应为 2，得到 %+v", applied["recalculatedLedgerRows"])
	}
	// 落地响应也要带差异明细，否则前端会把预览覆盖成「无差异」。
	if channels, _ := applied["channels"].([]any); len(channels) != 1 {
		t.Fatalf("导入结果 channels 应含 1 个小项，得到 %+v", applied["channels"])
	}

	// 换成团队模板后分值应变成 15/10，证明重算确实落库。
	points := env.ledgerPointsByTeam(t)
	if points[ids.teamA] != 15 || points[ids.teamB] != 10 {
		t.Fatalf("导入后流水分值应为 A=15 B=10，得到 %+v", points)
	}
}

// 重算失败必须显式报错，且整个重算在同一事务里回滚，不能留下「新规则 + 部分新积分」（P1-12）。
func TestRulesImportRecomputeFailureRollsBackAndReports(t *testing.T) {
	env := newTestEnv(t)
	ids := env.seed(t)
	env.createUser("admin", "admin-pass", "admin")
	client, _ := env.client()
	env.login(client, "admin", "admin-pass")
	env.publishTwoResults(t, client, ids)

	var profileID int64
	if err := env.ev.QueryRow(`SELECT id FROM scoring_profiles WHERE code = 'individual_top6'`).Scan(&profileID); err != nil {
		t.Fatalf("读取积分模板: %v", err)
	}
	// 第二个项目 compare=none 却配了 basis=result 通道，重算到这里必然报错。
	// 项目编码排在 M100 之后，保证替换到的第一个通道属于 M100。
	broken := env.insert(t,
		`INSERT INTO events (sport_id, code, name, event_type, result_mode, result_type, compare, scored, multiplier, status)
		 VALUES (?, 'Z_BROKEN', '损坏项目', 'individual', 'auto', 'time', 'none', 1, 1, 'ongoing')`, ids.sport)
	brokenCat := env.insert(t,
		`INSERT INTO event_categories (event_id, name, multiplier, sort_order) VALUES (?, '男子', 1, 0)`, broken)
	env.exec(t, `INSERT INTO event_score_channels (event_id, scope, basis, profile_id, sort_order)
	             VALUES (?, 'athlete', 'result', ?, 0)`, broken, profileID)
	brokenEntry := env.insert(t,
		`INSERT INTO entries (event_id, category_id, team_id, athlete_id, status)
		 VALUES (?, ?, ?, ?, 'registered')`, broken, brokenCat, ids.teamA, ids.athleteA)
	env.insert(t, `INSERT INTO results (event_id, entry_id, result_value, result_text, unit, status, state, rank)
	               VALUES (?, ?, 11.0, '11.00', 's', 'ok', 'published', 1)`, broken, brokenEntry)

	before := env.ledgerPointsByTeam(t)
	pack := env.exportRulesYAML(t, client)
	changed := strings.Replace(pack, "profile: individual_top6", "profile: team_top6", 1)
	if changed == pack {
		t.Fatalf("规则包里没有可替换的计分通道")
	}

	status, raw := env.doRaw(client, http.MethodPost, "/api/rules/import", []byte(changed), "application/yaml", true)
	if status != http.StatusInternalServerError {
		t.Fatalf("重算失败应 500，得到 %d %s", status, raw)
	}
	if !strings.Contains(string(raw), "积分重算失败") {
		t.Fatalf("错误信息应说明重算失败，得到 %s", raw)
	}

	// 规则本身已经落库（Apply 先提交），但第一个项目的重算必须随第二个项目一起回滚。
	var code string
	if err := env.ev.QueryRow(`SELECT p.code FROM event_score_channels c
	                             JOIN scoring_profiles p ON p.id = c.profile_id
	                            WHERE c.event_id = ?`, ids.event).Scan(&code); err != nil {
		t.Fatalf("查询导入后的计分通道: %v", err)
	}
	if code != "team_top6" {
		t.Fatalf("规则应已落库（通道改为 team_top6），得到 %q", code)
	}
	after := env.ledgerPointsByTeam(t)
	if after[ids.teamA] != before[ids.teamA] || after[ids.teamB] != before[ids.teamB] {
		t.Fatalf("重算失败应整体回滚，流水不应变化：before=%+v after=%+v", before, after)
	}
}