package teachingassets

import (
	"context"
	"encoding/json"
	"fmt"

	"github.com/jackc/pgx/v5/pgxpool"
)

type PostgresStore struct {
	pool *pgxpool.Pool
}

func NewPostgresStore(pool *pgxpool.Pool) *PostgresStore {
	return &PostgresStore{pool: pool}
}

func toJSON(v any) string {
	b, _ := json.Marshal(v)
	return string(b)
}

func (s *PostgresStore) SavePrompt(prompt PromptCandidate) (PromptCandidate, error) {
	_, err := s.pool.Exec(context.Background(),
		`INSERT INTO teaching_asset_prompts (id, concept_id, asset_type, prompt, model_key, review_state, requires_model_id_verification, source_evidence, created_at)
		 VALUES ($1, $2, $3, $4, $5, $6, $7, $8::jsonb, $9)`,
		prompt.ID, prompt.Concept.ID, string(prompt.AssetType), prompt.Prompt,
		prompt.ModelKey, string(prompt.ReviewState), prompt.RequiresModelIDVerification,
		toJSON(prompt.SourceEvidence), prompt.CreatedAt,
	)
	if err != nil {
		return PromptCandidate{}, fmt.Errorf("insert prompt: %w", err)
	}
	return prompt, nil
}

func (s *PostgresStore) Snapshot() Snapshot {
	rows, _ := s.pool.Query(context.Background(),
		`SELECT id, concept_id, asset_type, prompt, model_key, review_state, requires_model_id_verification, source_evidence, created_at FROM teaching_asset_prompts`)
	defer rows.Close()

	var prompts []PromptCandidate
	for rows.Next() {
		var p PromptCandidate
		var evidenceJSON string
		rows.Scan(&p.ID, &p.Concept.ID, &p.AssetType, &p.Prompt, &p.ModelKey,
			&p.ReviewState, &p.RequiresModelIDVerification, &evidenceJSON, &p.CreatedAt)
		json.Unmarshal([]byte(evidenceJSON), &p.SourceEvidence)
		prompts = append(prompts, p)
	}
	return Snapshot{Prompts: prompts}
}