package models

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

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

type Campaign struct {
	ID           string          `json:"id"`
	RepositoryID string          `json:"repository_id"`
	Name         string          `json:"name"`
	Type         string          `json:"type"`
	Status       string          `json:"status"`
	StartedAt    time.Time       `json:"started_at"`
	FinishedAt   *time.Time      `json:"finished_at,omitempty"`
	Tags         json.RawMessage `json:"tags,omitempty"`
	Metadata     json.RawMessage `json:"metadata,omitempty"`
	CreatedAt    time.Time       `json:"created_at"`

	// Joined fields.
	RepoName      string `json:"repo_name,omitempty"`
	ArtifactCount int    `json:"artifact_count,omitempty"`
}

type CreateCampaignParams struct {
	RepositoryID string
	Name         string
	Type         string
	Tags         json.RawMessage
	Metadata     json.RawMessage
}

func CreateCampaign(ctx context.Context, pool *pgxpool.Pool, p CreateCampaignParams) (*Campaign, error) {
	if p.Tags == nil {
		p.Tags = json.RawMessage("{}")
	}
	if p.Metadata == nil {
		p.Metadata = json.RawMessage("{}")
	}

	c := &Campaign{}
	err := pool.QueryRow(ctx, `
		INSERT INTO campaigns (repository_id, name, type, tags, metadata)
		VALUES ($1, $2, $3, $4, $5)
		RETURNING id, repository_id, name, type, status, started_at, finished_at, tags, metadata, created_at
	`, p.RepositoryID, p.Name, p.Type, p.Tags, p.Metadata).Scan(
		&c.ID, &c.RepositoryID, &c.Name, &c.Type, &c.Status,
		&c.StartedAt, &c.FinishedAt, &c.Tags, &c.Metadata, &c.CreatedAt,
	)
	if err != nil {
		return nil, fmt.Errorf("creating campaign: %w", err)
	}
	return c, nil
}

func FinishCampaign(ctx context.Context, pool *pgxpool.Pool, id string) error {
	_, err := pool.Exec(ctx, `
		UPDATE campaigns SET status = 'finished', finished_at = NOW() WHERE id = $1
	`, id)
	if err != nil {
		return fmt.Errorf("finishing campaign: %w", err)
	}
	return nil
}

func GetCampaign(ctx context.Context, pool *pgxpool.Pool, id string) (*Campaign, error) {
	c := &Campaign{}
	err := pool.QueryRow(ctx, `
		SELECT c.id, c.repository_id, c.name, c.type, c.status, c.started_at, c.finished_at,
		       c.tags, c.metadata, c.created_at,
		       r.name,
		       (SELECT COUNT(*) FROM artifacts a WHERE a.campaign_id = c.id)
		FROM campaigns c
		JOIN repositories r ON r.id = c.repository_id
		WHERE c.id = $1
	`, id).Scan(
		&c.ID, &c.RepositoryID, &c.Name, &c.Type, &c.Status,
		&c.StartedAt, &c.FinishedAt, &c.Tags, &c.Metadata, &c.CreatedAt,
		&c.RepoName, &c.ArtifactCount,
	)
	if err != nil {
		return nil, fmt.Errorf("getting campaign: %w", err)
	}
	return c, nil
}

func ListCampaigns(ctx context.Context, pool *pgxpool.Pool, repoID string, limit, offset int) ([]Campaign, int, error) {
	if limit <= 0 {
		limit = 50
	}

	baseQuery := `
		FROM campaigns c
		JOIN repositories r ON r.id = c.repository_id
		WHERE 1=1
	`
	args := []any{}
	argN := 1

	if repoID != "" {
		baseQuery += fmt.Sprintf(" AND c.repository_id = $%d", argN)
		args = append(args, repoID)
		argN++
	}

	var total int
	err := pool.QueryRow(ctx, "SELECT COUNT(*) "+baseQuery, args...).Scan(&total)
	if err != nil {
		return nil, 0, fmt.Errorf("counting campaigns: %w", err)
	}

	selectQuery := fmt.Sprintf(`
		SELECT c.id, c.repository_id, c.name, c.type, c.status, c.started_at, c.finished_at,
		       c.tags, c.metadata, c.created_at,
		       r.name,
		       (SELECT COUNT(*) FROM artifacts a WHERE a.campaign_id = c.id)
		%s
		ORDER BY c.created_at DESC
		LIMIT $%d OFFSET $%d
	`, baseQuery, argN, argN+1)
	args = append(args, limit, offset)

	rows, err := pool.Query(ctx, selectQuery, args...)
	if err != nil {
		return nil, 0, fmt.Errorf("listing campaigns: %w", err)
	}
	defer rows.Close()

	var campaigns []Campaign
	for rows.Next() {
		var c Campaign
		if err := rows.Scan(
			&c.ID, &c.RepositoryID, &c.Name, &c.Type, &c.Status,
			&c.StartedAt, &c.FinishedAt, &c.Tags, &c.Metadata, &c.CreatedAt,
			&c.RepoName, &c.ArtifactCount,
		); err != nil {
			return nil, 0, fmt.Errorf("scanning campaign: %w", err)
		}
		campaigns = append(campaigns, c)
	}
	return campaigns, total, nil
}