package blind

import (
	"context"
	"database/sql"
	"os"
	"path/filepath"
	"testing"

	_ "github.com/tursodatabase/go-libsql"
)

// setupTestDB creates a temporary test database with the required schema.
func setupTestDB(t *testing.T) *sql.DB {
	t.Helper()
	tmpDir := t.TempDir()
	dbPath := filepath.Join(tmpDir, "test.db")

	db, err := sql.Open("libsql", "file:"+dbPath)
	if err != nil {
		t.Fatalf("open test db: %v", err)
	}
	t.Cleanup(func() { db.Close() })

	// Create required tables
	stmts := []string{
		`CREATE TABLE chip_sets (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, is_builtin INTEGER NOT NULL DEFAULT 0, created_at INTEGER NOT NULL DEFAULT 0, updated_at INTEGER NOT NULL DEFAULT 0)`,
		`CREATE TABLE chip_denominations (id INTEGER PRIMARY KEY AUTOINCREMENT, chip_set_id INTEGER NOT NULL, value INTEGER NOT NULL, color_hex TEXT NOT NULL DEFAULT '#FFF', label TEXT NOT NULL DEFAULT '', sort_order INTEGER NOT NULL DEFAULT 0)`,
		`CREATE TABLE blind_structures (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, is_builtin INTEGER NOT NULL DEFAULT 0, game_type_default TEXT NOT NULL DEFAULT 'nlhe', notes TEXT NOT NULL DEFAULT '', created_at INTEGER NOT NULL DEFAULT 0, updated_at INTEGER NOT NULL DEFAULT 0)`,
		`CREATE TABLE blind_levels (id INTEGER PRIMARY KEY AUTOINCREMENT, structure_id INTEGER NOT NULL, position INTEGER NOT NULL, level_type TEXT NOT NULL DEFAULT 'round', game_type TEXT NOT NULL DEFAULT 'nlhe', small_blind INTEGER NOT NULL DEFAULT 0, big_blind INTEGER NOT NULL DEFAULT 0, ante INTEGER NOT NULL DEFAULT 0, bb_ante INTEGER NOT NULL DEFAULT 0, duration_seconds INTEGER NOT NULL DEFAULT 900, chip_up_denomination_value INTEGER, notes TEXT NOT NULL DEFAULT '')`,
		`CREATE TABLE tournaments (id TEXT PRIMARY KEY, name TEXT, template_id INTEGER, chip_set_id INTEGER, blind_structure_id INTEGER, payout_structure_id INTEGER, buyin_config_id INTEGER, points_formula_id INTEGER, status TEXT DEFAULT 'created', min_players INTEGER DEFAULT 2, max_players INTEGER, early_signup_bonus_chips INTEGER DEFAULT 0, early_signup_cutoff TEXT, punctuality_bonus_chips INTEGER DEFAULT 0, is_pko INTEGER DEFAULT 0, current_level INTEGER DEFAULT 0, clock_state TEXT DEFAULT 'stopped', clock_remaining_ns INTEGER DEFAULT 0, total_elapsed_ns INTEGER DEFAULT 0, hand_for_hand INTEGER DEFAULT 0, started_at INTEGER, ended_at INTEGER, created_at INTEGER DEFAULT 0, updated_at INTEGER DEFAULT 0)`,
	}
	for _, stmt := range stmts {
		if _, err := db.Exec(stmt); err != nil {
			t.Fatalf("create table: %v", err)
		}
	}

	// Insert standard chip set
	if _, err := db.Exec(`INSERT INTO chip_sets (id, name) VALUES (1, 'Standard')`); err != nil {
		t.Fatalf("insert chip set: %v", err)
	}
	denominations := []struct {
		value    int64
		colorHex string
	}{
		{25, "#FFFFFF"},
		{100, "#FF0000"},
		{500, "#00AA00"},
		{1000, "#000000"},
		{5000, "#0000FF"},
	}
	for _, d := range denominations {
		if _, err := db.Exec(`INSERT INTO chip_denominations (chip_set_id, value, color_hex) VALUES (1, ?, ?)`, d.value, d.colorHex); err != nil {
			t.Fatalf("insert denomination: %v", err)
		}
	}

	return db
}

func TestWizardGenerate_StandardTournament(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	levels, err := ws.Generate(ctx, WizardInput{
		PlayerCount:           20,
		StartingChips:         15000,
		TargetDurationMinutes: 240,
		ChipSetID:             1,
	})
	if err != nil {
		t.Fatalf("generate: %v", err)
	}

	if len(levels) == 0 {
		t.Fatal("expected at least 1 level")
	}

	// Check all levels have valid types
	hasRound := false
	hasBreak := false
	for _, l := range levels {
		if l.LevelType == "round" {
			hasRound = true
		}
		if l.LevelType == "break" {
			hasBreak = true
		}
		if l.LevelType != "round" && l.LevelType != "break" {
			t.Errorf("invalid level type: %s", l.LevelType)
		}
	}
	if !hasRound {
		t.Error("expected at least one round level")
	}
	if !hasBreak {
		t.Error("expected at least one break")
	}

	// Check positions are contiguous
	for i, l := range levels {
		if l.Position != i {
			t.Errorf("level %d: expected position %d, got %d", i, i, l.Position)
		}
	}

	// Check blinds are increasing for round levels
	prevBB := int64(0)
	for _, l := range levels {
		if l.LevelType == "round" {
			if l.BigBlind <= 0 {
				t.Errorf("level %d: big blind must be positive, got %d", l.Position, l.BigBlind)
			}
			if l.BigBlind < prevBB {
				t.Errorf("level %d: big blind %d not increasing from previous %d", l.Position, l.BigBlind, prevBB)
			}
			if l.SmallBlind >= l.BigBlind {
				t.Errorf("level %d: small blind %d >= big blind %d", l.Position, l.SmallBlind, l.BigBlind)
			}
			prevBB = l.BigBlind
		}
	}
}

func TestWizardGenerate_VariousPlayerCounts(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	for _, pc := range []int{10, 20, 40, 80} {
		t.Run(stringFromInt(pc)+"players", func(t *testing.T) {
			levels, err := ws.Generate(ctx, WizardInput{
				PlayerCount:           pc,
				StartingChips:         15000,
				TargetDurationMinutes: 240,
				ChipSetID:             1,
			})
			if err != nil {
				t.Fatalf("generate for %d players: %v", pc, err)
			}
			if len(levels) < 5 {
				t.Errorf("expected at least 5 levels for %d players, got %d", pc, len(levels))
			}

			// Verify structure is increasing
			prevBB := int64(0)
			for _, l := range levels {
				if l.LevelType == "round" && l.BigBlind < prevBB {
					t.Errorf("level %d: big blind %d < previous %d for %d players", l.Position, l.BigBlind, prevBB, pc)
				}
				if l.LevelType == "round" {
					prevBB = l.BigBlind
				}
			}
		})
	}
}

func TestWizardGenerate_BlindsAlignWithDenominations(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	levels, err := ws.Generate(ctx, WizardInput{
		PlayerCount:           20,
		StartingChips:         15000,
		TargetDurationMinutes: 240,
		ChipSetID:             1,
	})
	if err != nil {
		t.Fatalf("generate: %v", err)
	}

	denoms := []int64{25, 100, 500, 1000, 5000}

	for _, l := range levels {
		if l.LevelType != "round" {
			continue
		}
		if !isDenomAligned(l.SmallBlind, denoms) {
			t.Errorf("level %d: SB %d not aligned with denominations", l.Position, l.SmallBlind)
		}
		if !isDenomAligned(l.BigBlind, denoms) {
			t.Errorf("level %d: BB %d not aligned with denominations", l.Position, l.BigBlind)
		}
		if l.Ante > 0 && !isDenomAligned(l.Ante, denoms) {
			t.Errorf("level %d: ante %d not aligned with denominations", l.Position, l.Ante)
		}
	}
}

func TestWizardGenerate_ShortTournament(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	levels, err := ws.Generate(ctx, WizardInput{
		PlayerCount:           10,
		StartingChips:         10000,
		TargetDurationMinutes: 60,
		ChipSetID:             1,
	})
	if err != nil {
		t.Fatalf("generate: %v", err)
	}

	if len(levels) < 3 {
		t.Errorf("expected at least 3 levels for 1hr tournament, got %d", len(levels))
	}
}

func TestWizardGenerate_LongTournament(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	levels, err := ws.Generate(ctx, WizardInput{
		PlayerCount:           20,
		StartingChips:         50000,
		TargetDurationMinutes: 480,
		ChipSetID:             1,
	})
	if err != nil {
		t.Fatalf("generate: %v", err)
	}

	if len(levels) < 5 {
		t.Errorf("expected at least 5 levels for 8hr tournament, got %d", len(levels))
	}

	// Check breaks are present
	breakCount := 0
	for _, l := range levels {
		if l.LevelType == "break" {
			breakCount++
		}
	}
	if breakCount == 0 {
		t.Error("expected at least one break in 8hr tournament")
	}
}

func TestWizardGenerate_InvalidInputs(t *testing.T) {
	if os.Getenv("CGO_ENABLED") == "0" {
		t.Skip("requires CGO for libsql")
	}

	db := setupTestDB(t)
	ws := NewWizardService(db)
	ctx := context.Background()

	tests := []struct {
		name  string
		input WizardInput
	}{
		{"too few players", WizardInput{PlayerCount: 1, StartingChips: 10000, TargetDurationMinutes: 120, ChipSetID: 1}},
		{"zero chips", WizardInput{PlayerCount: 10, StartingChips: 0, TargetDurationMinutes: 120, ChipSetID: 1}},
		{"too short", WizardInput{PlayerCount: 10, StartingChips: 10000, TargetDurationMinutes: 10, ChipSetID: 1}},
		{"missing chip set", WizardInput{PlayerCount: 10, StartingChips: 10000, TargetDurationMinutes: 120, ChipSetID: 999}},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			_, err := ws.Generate(ctx, tc.input)
			if err == nil {
				t.Error("expected error for invalid input")
			}
		})
	}
}

// isDenomAligned checks if a value is a multiple of any denomination.
func isDenomAligned(value int64, denoms []int64) bool {
	for _, d := range denoms {
		if value%d == 0 {
			return true
		}
	}
	return false
}

// stringFromInt converts int to string for test names.
func stringFromInt(n int) string {
	s := ""
	if n == 0 {
		return "0"
	}
	for n > 0 {
		s = string(rune('0'+n%10)) + s
		n /= 10
	}
	return s
}