package services

import (
	"context"

	"git.golem15.com/golem15/sm-golem-plugin/models"
	"gorm.io/gorm"
)

// The functions below port the WinterCMS plugin's Settings model over the
// golem15_golem_models rows (in sort_order, then id order). Every config
// they return is an operator's model: Trusted is set. A nil db means no
// model is configured.

// Models is Settings::getModels: the enabled models, in order. Each keeps
// its Position among all models, enabled or not, as PHP's array_filter
// keeps the repeater keys.
func Models(ctx context.Context, db *gorm.DB) ([]*ModelConfig, error) {
	if db == nil {
		return nil, nil
	}
	var rows []models.AiModel
	if err := db.WithContext(ctx).Order("sort_order, id").Find(&rows).Error; err != nil {
		return nil, err
	}
	var out []*ModelConfig
	for i := range rows {
		if !rows[i].IsEnabled {
			continue
		}
		c := modelConfigFrom(&rows[i])
		c.Position = i
		out = append(out, c)
	}
	return out, nil
}

// DefaultModel is Settings::getDefaultModel: the first enabled model
// marked default, else the model at position 0 when it is enabled. PHP's
// `$models[0] ?? null` reads the filtered array by key, so a disabled
// first model means no default even when later models are enabled.
func DefaultModel(ctx context.Context, db *gorm.DB) (*ModelConfig, error) {
	all, err := Models(ctx, db)
	if err != nil {
		return nil, err
	}
	for _, m := range all {
		if m.isDefault {
			return m, nil
		}
	}
	for _, m := range all {
		if m.Position == 0 {
			return m, nil
		}
	}
	return nil, nil
}

// VisionModel is Settings::getVisionModel: the first enabled model that
// accepts images.
func VisionModel(ctx context.Context, db *gorm.DB) (*ModelConfig, error) {
	return firstModel(ctx, db, func(m *ModelConfig) bool { return m.AcceptsImages })
}

// ImageModel is Settings::getImageModel: the first enabled model that
// generates images.
func ImageModel(ctx context.Context, db *gorm.DB) (*ModelConfig, error) {
	return firstModel(ctx, db, func(m *ModelConfig) bool { return m.GeneratesImages })
}

// FileModel is Settings::getFileModel: the first enabled model with a
// files endpoint.
func FileModel(ctx context.Context, db *gorm.DB) (*ModelConfig, error) {
	return firstModel(ctx, db, func(m *ModelConfig) bool { return m.HasFilesEndpoint })
}

// ModelByName is Settings::getModelByName: the first enabled model named
// name.
func ModelByName(ctx context.Context, db *gorm.DB, name string) (*ModelConfig, error) {
	return firstModel(ctx, db, func(m *ModelConfig) bool { return m.Name == name })
}

func firstModel(ctx context.Context, db *gorm.DB, match func(*ModelConfig) bool) (*ModelConfig, error) {
	all, err := Models(ctx, db)
	if err != nil {
		return nil, err
	}
	for _, m := range all {
		if match(m) {
			return m, nil
		}
	}
	return nil, nil
}

func modelConfigFrom(row *models.AiModel) *ModelConfig {
	c := &ModelConfig{
		Name:             row.Name,
		Adapter:          row.Adapter,
		APIKey:           row.APIKey.Reveal(),
		Model:            row.Model,
		HasFilesEndpoint: row.HasFilesEndpoint,
		AcceptsImages:    row.AcceptsImages,
		GeneratesImages:  row.GeneratesImages,
		Trusted:          true,
		isDefault:        row.IsDefault,
	}
	if row.BaseURL != nil {
		c.BaseURL = *row.BaseURL
	}
	if row.SystemPrompt != nil {
		c.SystemPrompt = *row.SystemPrompt
	}
	if row.MaxCompletionTokens != nil {
		c.MaxCompletionTokens = *row.MaxCompletionTokens
	}
	return c
}