package db

import (
	"context"
	"time"

	"github.com/pkg/errors"
	"github.com/uptrace/bun"
)

type FixtureResult struct {
	bun.BaseModel `bun:"table:fixture_results,alias:fr"`

	ID                int    `bun:"id,pk,autoincrement"`
	FixtureID         int    `bun:",notnull,unique"`
	Winner            string `bun:",notnull"`
	HomeScore         int    `bun:",notnull"`
	AwayScore         int    `bun:",notnull"`
	MatchType         string
	Arena             string
	EndReason         string
	PeriodsEnabled    bool
	CustomMercyRule   int
	MatchLength       int
	CreatedAt         int64 `bun:",notnull"`
	UpdatedAt         *int64
	UploadedByUserID  int  `bun:",notnull"`
	Finalized         bool `bun:",default:false"`
	TamperingDetected bool `bun:",default:false"`
	TamperingReason   *string

	Fixture     *Fixture                    `bun:"rel:belongs-to,join:fixture_id=id"`
	UploadedBy  *User                       `bun:"rel:belongs-to,join:uploaded_by_user_id=id"`
	PlayerStats []*FixtureResultPlayerStats `bun:"rel:has-many,join:id=fixture_result_id"`
}

type FixtureResultPlayerStats struct {
	bun.BaseModel `bun:"table:fixture_result_player_stats,alias:frps"`

	ID               int    `bun:"id,pk,autoincrement"`
	FixtureResultID  int    `bun:",notnull"`
	PeriodNum        int    `bun:",notnull"`
	PlayerID         *int   // NULL for unmapped/free agents
	PlayerGameUserID string `bun:",notnull"`
	PlayerUsername   string `bun:",notnull"`
	TeamID           *int   // NULL for unmapped
	Team             string `bun:",notnull"` // 'home' or 'away'

	// All stats as INT (nullable)
	Goals             *int
	Assists           *int
	PrimaryAssists    *int
	SecondaryAssists  *int
	Saves             *int
	Blocks            *int
	Shots             *int
	Turnovers         *int
	Takeaways         *int
	Passes            *int
	PossessionTimeSec *int
	FaceoffsWon       *int
	FaceoffsLost      *int
	PostHits          *int
	OvertimeGoals     *int
	GameWinningGoals  *int
	Score             *int
	ContributedGoals  *int
	ConcededGoals     *int
	GamesPlayed       *int
	Wins              *int
	Losses            *int
	OvertimeWins      *int
	OvertimeLosses    *int
	Ties              *int
	Shutouts          *int
	ShutoutsAgainst   *int
	HasMercyRuled     *int
	WasMercyRuled     *int
	PeriodsPlayed     *int

	FixtureResult *FixtureResult `bun:"rel:belongs-to,join:fixture_result_id=id"`
	Player        *Player        `bun:"rel:belongs-to,join:player_id=id"`
	TeamRel       *Team          `bun:"rel:belongs-to,join:team_id=id"`
}

// PlayerWithPlayStatus is a helper struct for overview display
type PlayerWithPlayStatus struct {
	Player    *Player
	Played    bool
	IsManager bool
	Stats     *FixtureResultPlayerStats // Period 3 (final cumulative) stats, nil if no result
}

// InsertFixtureResult stores a new match result with all player stats in a single transaction.
func InsertFixtureResult(
	ctx context.Context,
	tx bun.Tx,
	result *FixtureResult,
	playerStats []*FixtureResultPlayerStats,
	audit *AuditMeta,
) (*FixtureResult, error) {
	if result == nil {
		return nil, errors.New("result cannot be nil")
	}

	result.CreatedAt = time.Now().Unix()

	err := Insert(tx, result).WithAudit(audit, &AuditInfo{
		Action:       "fixture_results.create",
		ResourceType: "fixture_result",
		ResourceID:   nil,
		Details: map[string]any{
			"fixture_id":         result.FixtureID,
			"winner":             result.Winner,
			"home_score":         result.HomeScore,
			"away_score":         result.AwayScore,
			"tampering_detected": result.TamperingDetected,
		},
	}).Exec(ctx)
	if err != nil {
		return nil, errors.Wrap(err, "Insert result")
	}

	// Set the fixture_result_id on all player stats
	for _, ps := range playerStats {
		ps.FixtureResultID = result.ID
	}

	// Insert player stats in bulk
	if len(playerStats) > 0 {
		err = InsertMultiple(tx, playerStats).Exec(ctx)
		if err != nil {
			return nil, errors.Wrap(err, "InsertMultiple player stats")
		}
	}

	return result, nil
}

// GetFixtureResult retrieves a result with all player stats for a fixture.
// Returns nil, nil if no result exists.
func GetFixtureResult(ctx context.Context, tx bun.Tx, fixtureID int) (*FixtureResult, error) {
	result := new(FixtureResult)
	err := tx.NewSelect().
		Model(result).
		Where("fr.fixture_id = ?", fixtureID).
		Relation("Fixture").
		Relation("UploadedBy").
		Relation("PlayerStats", func(q *bun.SelectQuery) *bun.SelectQuery {
			return q.Order("frps.team ASC", "frps.period_num ASC", "frps.player_username ASC")
		}).
		Relation("PlayerStats.Player").
		Scan(ctx)
	if err != nil {
		if err.Error() == "sql: no rows in result set" {
			return nil, nil
		}
		return nil, errors.Wrap(err, "tx.NewSelect")
	}
	return result, nil
}

// GetPendingFixtureResult retrieves a non-finalized result for review/edit.
// Returns nil, nil if no pending result exists.
func GetPendingFixtureResult(ctx context.Context, tx bun.Tx, fixtureID int) (*FixtureResult, error) {
	result := new(FixtureResult)
	err := tx.NewSelect().
		Model(result).
		Where("fr.fixture_id = ?", fixtureID).
		Where("fr.finalized = false").
		Relation("Fixture").
		Relation("UploadedBy").
		Relation("PlayerStats", func(q *bun.SelectQuery) *bun.SelectQuery {
			return q.Order("frps.team ASC", "frps.period_num ASC", "frps.player_username ASC")
		}).
		Relation("PlayerStats.Player").
		Scan(ctx)
	if err != nil {
		if err.Error() == "sql: no rows in result set" {
			return nil, nil
		}
		return nil, errors.Wrap(err, "tx.NewSelect")
	}
	return result, nil
}

// FinalizeFixtureResult marks a pending result as finalized.
func FinalizeFixtureResult(
	ctx context.Context,
	tx bun.Tx,
	fixtureID int,
	audit *AuditMeta,
) error {
	result, err := GetPendingFixtureResult(ctx, tx, fixtureID)
	if err != nil {
		return errors.Wrap(err, "GetPendingFixtureResult")
	}
	if result == nil {
		return BadRequest("no pending result to finalize")
	}

	now := time.Now().Unix()
	result.Finalized = true
	result.UpdatedAt = &now

	err = UpdateByID(tx, result.ID, result).
		Column("finalized", "updated_at").
		WithAudit(audit, &AuditInfo{
			Action:       "fixture_results.finalize",
			ResourceType: "fixture_result",
			ResourceID:   result.ID,
			Details: map[string]any{
				"fixture_id": fixtureID,
			},
		}).Exec(ctx)
	if err != nil {
		return errors.Wrap(err, "UpdateByID")
	}
	return nil
}

// DeleteFixtureResult removes a pending result and all associated player stats (CASCADE).
func DeleteFixtureResult(
	ctx context.Context,
	tx bun.Tx,
	fixtureID int,
	audit *AuditMeta,
) error {
	result, err := GetPendingFixtureResult(ctx, tx, fixtureID)
	if err != nil {
		return errors.Wrap(err, "GetPendingFixtureResult")
	}
	if result == nil {
		return BadRequest("no pending result to discard")
	}

	err = DeleteByID[FixtureResult](tx, result.ID).
		WithAudit(audit, &AuditInfo{
			Action:       "fixture_results.discard",
			ResourceType: "fixture_result",
			ResourceID:   result.ID,
			Details: map[string]any{
				"fixture_id": fixtureID,
			},
		}).Delete(ctx)
	if err != nil {
		return errors.Wrap(err, "DeleteByID")
	}
	return nil
}

// GetFinalizedResultsForFixtures returns finalized results for a list of fixture IDs.
// Returns a map of fixtureID -> *FixtureResult (without player stats for efficiency).
func GetFinalizedResultsForFixtures(ctx context.Context, tx bun.Tx, fixtureIDs []int) (map[int]*FixtureResult, error) {
	if len(fixtureIDs) == 0 {
		return map[int]*FixtureResult{}, nil
	}
	results, err := GetList[FixtureResult](tx).
		Where("fixture_id IN (?)", bun.In(fixtureIDs)).
		Where("finalized = true").
		GetAll(ctx)
	if err != nil {
		return nil, errors.Wrap(err, "GetList")
	}
	resultMap := make(map[int]*FixtureResult, len(results))
	for _, r := range results {
		resultMap[r.FixtureID] = r
	}
	return resultMap, nil
}

// GetFixtureTeamRosters returns all team players with participation status for a fixture.
// Returns: map["home"|"away"] -> []*PlayerWithPlayStatus
func GetFixtureTeamRosters(
	ctx context.Context,
	tx bun.Tx,
	fixture *Fixture,
	result *FixtureResult,
) (map[string][]*PlayerWithPlayStatus, error) {
	if fixture == nil {
		return nil, errors.New("fixture cannot be nil")
	}

	rosters := map[string][]*PlayerWithPlayStatus{}

	// Get home team roster
	homeRosters := []*TeamRoster{}
	err := tx.NewSelect().
		Model(&homeRosters).
		Where("tr.team_id = ?", fixture.HomeTeamID).
		Where("tr.season_id = ?", fixture.SeasonID).
		Where("tr.league_id = ?", fixture.LeagueID).
		Relation("Player", func(q *bun.SelectQuery) *bun.SelectQuery {
			return q.Relation("User")
		}).
		Scan(ctx)
	if err != nil {
		return nil, errors.Wrap(err, "tx.NewSelect home roster")
	}

	// Get away team roster
	awayRosters := []*TeamRoster{}
	err = tx.NewSelect().
		Model(&awayRosters).
		Where("tr.team_id = ?", fixture.AwayTeamID).
		Where("tr.season_id = ?", fixture.SeasonID).
		Where("tr.league_id = ?", fixture.LeagueID).
		Relation("Player", func(q *bun.SelectQuery) *bun.SelectQuery {
			return q.Relation("User")
		}).
		Scan(ctx)
	if err != nil {
		return nil, errors.Wrap(err, "tx.NewSelect away roster")
	}

	// Build maps of player IDs that played and their period 3 stats
	playedPlayerIDs := map[int]bool{}
	playerStatsByID := map[int]*FixtureResultPlayerStats{}
	if result != nil {
		for _, ps := range result.PlayerStats {
			if ps.PlayerID != nil {
				playedPlayerIDs[*ps.PlayerID] = true
				if ps.PeriodNum == 3 {
					playerStatsByID[*ps.PlayerID] = ps
				}
			}
		}
	}

	// Build home roster with play status and stats
	for _, r := range homeRosters {
		played := false
		var stats *FixtureResultPlayerStats
		if result != nil && r.Player != nil {
			played = playedPlayerIDs[r.Player.ID]
			stats = playerStatsByID[r.Player.ID]
		}
		rosters["home"] = append(rosters["home"], &PlayerWithPlayStatus{
			Player:    r.Player,
			Played:    played,
			IsManager: r.IsManager,
			Stats:     stats,
		})
	}

	// Build away roster with play status and stats
	for _, r := range awayRosters {
		played := false
		var stats *FixtureResultPlayerStats
		if result != nil && r.Player != nil {
			played = playedPlayerIDs[r.Player.ID]
			stats = playerStatsByID[r.Player.ID]
		}
		rosters["away"] = append(rosters["away"], &PlayerWithPlayStatus{
			Player:    r.Player,
			Played:    played,
			IsManager: r.IsManager,
			Stats:     stats,
		})
	}

	return rosters, nil
}