package main

import (
	"database/sql"
	"fmt"
)

func ensureSchema(db *sql.DB) error {
	stmts := []string{
		`CREATE TABLE IF NOT EXISTS settings(
			id TINYINT PRIMARY KEY,
			days_per_month INT NOT NULL DEFAULT 2,
			current_month TINYINT NOT NULL DEFAULT 1,
			current_day TINYINT NOT NULL DEFAULT 1
		)`,
		`ALTER TABLE settings ADD COLUMN IF NOT EXISTS current_month TINYINT NOT NULL DEFAULT 1`,
		`ALTER TABLE settings ADD COLUMN IF NOT EXISTS current_day TINYINT NOT NULL DEFAULT 1`,
		`INSERT INTO settings(id,days_per_month,current_month,current_day) VALUES (1,2,1,1) ON DUPLICATE KEY UPDATE id=id`,
		`UPDATE settings SET current_month=1 WHERE current_month < 1 OR current_month > 12`,
		`UPDATE settings SET current_day=1 WHERE current_day < 1`,

		`CREATE TABLE IF NOT EXISTS fields(
			id BIGINT AUTO_INCREMENT PRIMARY KEY,
			number INT NOT NULL UNIQUE,
			name VARCHAR(120) NOT NULL DEFAULT '',
			owned TINYINT(1) NOT NULL DEFAULT 0,
			group_key VARCHAR(64) NOT NULL DEFAULT '',
			group_name VARCHAR(120) NOT NULL DEFAULT '',
			created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
		)`,
		`ALTER TABLE fields ADD COLUMN IF NOT EXISTS owned TINYINT(1) NOT NULL DEFAULT 0`,
		`ALTER TABLE fields ADD COLUMN IF NOT EXISTS group_key VARCHAR(64) NOT NULL DEFAULT ''`,
		`ALTER TABLE fields ADD COLUMN IF NOT EXISTS group_name VARCHAR(120) NOT NULL DEFAULT ''`,

		`CREATE TABLE IF NOT EXISTS crops(
			id BIGINT AUTO_INCREMENT PRIMARY KEY,
			name VARCHAR(80) NOT NULL UNIQUE,
			sow_start_month TINYINT NOT NULL,
			sow_end_month TINYINT NOT NULL,
			grow_months TINYINT NOT NULL
		)`,

		`CREATE TABLE IF NOT EXISTS plans(
			id BIGINT AUTO_INCREMENT PRIMARY KEY,
			field_id BIGINT NULL,
			target_ref VARCHAR(80) NOT NULL DEFAULT '',
			target_name VARCHAR(140) NOT NULL DEFAULT '',
			crop_id BIGINT NOT NULL,
			start_month TINYINT NOT NULL,
			start_day TINYINT NOT NULL,
			harvest_month TINYINT NOT NULL,
			harvest_day TINYINT NOT NULL,
			notes VARCHAR(255) NOT NULL DEFAULT '',
			created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
			CONSTRAINT fk_plans_fields FOREIGN KEY(field_id) REFERENCES fields(id) ON DELETE CASCADE,
			CONSTRAINT fk_plans_crops FOREIGN KEY(crop_id) REFERENCES crops(id) ON DELETE RESTRICT
		)`,
		`ALTER TABLE plans MODIFY COLUMN field_id BIGINT NULL`,
		`ALTER TABLE plans ADD COLUMN IF NOT EXISTS target_ref VARCHAR(80) NOT NULL DEFAULT '' AFTER field_id`,
		`ALTER TABLE plans ADD COLUMN IF NOT EXISTS target_name VARCHAR(140) NOT NULL DEFAULT '' AFTER target_ref`,
	}
	for _, stmt := range stmts {
		if _, err := db.Exec(stmt); err != nil {
			return err
		}
	}
	return seedCrops(db)
}

func (a *App) getSettings() (Settings, error) {
	var s Settings
	err := a.db.QueryRow(`SELECT days_per_month,current_month,current_day FROM settings WHERE id=1`).
		Scan(&s.DaysPerMonth, &s.CurrentMonth, &s.CurrentDay)
	return s, err
}

func (a *App) listFields() ([]Field, error) {
	rows, err := a.db.Query(`SELECT id,number,name,owned,COALESCE(group_key,''),COALESCE(group_name,'') FROM fields ORDER BY number`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []Field
	for rows.Next() {
		var f Field
		if err := rows.Scan(&f.ID, &f.Number, &f.Name, &f.Owned, &f.GroupKey, &f.GroupName); err != nil {
			return nil, err
		}
		out = append(out, f)
	}
	return out, rows.Err()
}

func (a *App) getFieldsByIDs(ids []int64) ([]Field, error) {
	args := make([]any, 0, len(ids))
	for _, id := range ids {
		args = append(args, id)
	}
	q := fmt.Sprintf(`SELECT id,number,name,owned,COALESCE(group_key,''),COALESCE(group_name,'') FROM fields WHERE id IN (%s)`, placeholders(len(ids)))
	rows, err := a.db.Query(q, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []Field
	for rows.Next() {
		var f Field
		if err := rows.Scan(&f.ID, &f.Number, &f.Name, &f.Owned, &f.GroupKey, &f.GroupName); err != nil {
			return nil, err
		}
		out = append(out, f)
	}
	return out, rows.Err()
}

func (a *App) listCrops() ([]Crop, error) {
	rows, err := a.db.Query(`SELECT id,name,sow_start_month,sow_end_month,grow_months FROM crops ORDER BY name`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []Crop
	for rows.Next() {
		var c Crop
		if err := rows.Scan(&c.ID, &c.Name, &c.SowStartMonth, &c.SowEndMonth, &c.GrowMonths); err != nil {
			return nil, err
		}
		out = append(out, c)
	}
	return out, rows.Err()
}

func (a *App) listPlans() ([]Plan, error) {
	rows, err := a.db.Query(`
		SELECT p.id,p.field_id,COALESCE(p.target_ref,''),COALESCE(p.target_name,''),p.crop_id,COALESCE(c.name,''),p.start_month,p.start_day,p.harvest_month,p.harvest_day,COALESCE(p.notes,'')
		FROM plans p
		JOIN crops c ON c.id=p.crop_id
		ORDER BY p.start_month,p.start_day,p.id DESC`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []Plan
	for rows.Next() {
		var p Plan
		if err := rows.Scan(&p.ID, &p.FieldID, &p.TargetRef, &p.TargetName, &p.CropID, &p.CropName, &p.StartMonth, &p.StartDay, &p.HarvestMonth, &p.HarvestDay, &p.Notes); err != nil {
			return nil, err
		}
		out = append(out, p)
	}
	return out, rows.Err()
}

func seedCrops(db *sql.DB) error {
	items := []Crop{
		{Name: "Weizen", SowStartMonth: 9, SowEndMonth: 11, GrowMonths: 10},
		{Name: "Gerste", SowStartMonth: 9, SowEndMonth: 10, GrowMonths: 9},
		{Name: "Hafer", SowStartMonth: 3, SowEndMonth: 4, GrowMonths: 4},
		{Name: "Raps", SowStartMonth: 8, SowEndMonth: 9, GrowMonths: 11},
		{Name: "Mais", SowStartMonth: 4, SowEndMonth: 5, GrowMonths: 6},
		{Name: "Sorghum", SowStartMonth: 4, SowEndMonth: 5, GrowMonths: 5},
		{Name: "Sojabohnen", SowStartMonth: 4, SowEndMonth: 5, GrowMonths: 5},
		{Name: "Sonnenblumen", SowStartMonth: 4, SowEndMonth: 5, GrowMonths: 5},
		{Name: "Kartoffeln", SowStartMonth: 3, SowEndMonth: 4, GrowMonths: 7},
		{Name: "Zuckerrueben", SowStartMonth: 3, SowEndMonth: 4, GrowMonths: 8},
		{Name: "Baumwolle", SowStartMonth: 2, SowEndMonth: 3, GrowMonths: 8},
	}
	for _, c := range items {
		if _, err := db.Exec(`INSERT INTO crops(name,sow_start_month,sow_end_month,grow_months) VALUES (?,?,?,?) ON DUPLICATE KEY UPDATE sow_start_month=VALUES(sow_start_month),sow_end_month=VALUES(sow_end_month),grow_months=VALUES(grow_months)`, c.Name, c.SowStartMonth, c.SowEndMonth, c.GrowMonths); err != nil {
			return err
		}
	}
	return nil
}