use crate::AppState;
use rusqlite::params;
use serde::{Deserialize, Serialize};
use tauri::State;

#[derive(Debug, Serialize, Deserialize)]
pub struct Client {
    pub id: Option<i64>,
    pub name: String,
    pub email: Option<String>,
    pub address: Option<String>,
    pub company: Option<String>,
    pub phone: Option<String>,
    pub tax_id: Option<String>,
    pub payment_terms: Option<String>,
    pub notes: Option<String>,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct Project {
    pub id: Option<i64>,
    pub client_id: Option<i64>,
    pub name: String,
    pub hourly_rate: f64,
    pub color: String,
    pub archived: bool,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct Task {
    pub id: Option<i64>,
    pub project_id: i64,
    pub name: String,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct TimeEntry {
    pub id: Option<i64>,
    pub project_id: i64,
    pub task_id: Option<i64>,
    pub description: Option<String>,
    pub start_time: String,
    pub end_time: Option<String>,
    pub duration: i64,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct Invoice {
    pub id: Option<i64>,
    pub client_id: i64,
    pub invoice_number: String,
    pub date: String,
    pub due_date: Option<String>,
    pub subtotal: f64,
    pub tax_rate: f64,
    pub tax_amount: f64,
    pub discount: f64,
    pub total: f64,
    pub notes: Option<String>,
    pub status: String,
}

// Client commands
#[tauri::command]
pub fn get_clients(state: State<AppState>) -> Result<Vec<Client>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let mut stmt = conn.prepare(
        "SELECT id, name, email, address, company, phone, tax_id, payment_terms, notes FROM clients ORDER BY name"
    ).map_err(|e| e.to_string())?;
    let clients = stmt.query_map([], |row| {
        Ok(Client {
            id: Some(row.get(0)?),
            name: row.get(1)?,
            email: row.get(2)?,
            address: row.get(3)?,
            company: row.get(4)?,
            phone: row.get(5)?,
            tax_id: row.get(6)?,
            payment_terms: row.get(7)?,
            notes: row.get(8)?,
        })
    }).map_err(|e| e.to_string())?;
    clients.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())
}

#[tauri::command]
pub fn create_client(state: State<AppState>, client: Client) -> Result<i64, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT INTO clients (name, email, address, company, phone, tax_id, payment_terms, notes) VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8)",
        params![client.name, client.email, client.address, client.company, client.phone, client.tax_id, client.payment_terms, client.notes],
    ).map_err(|e| e.to_string())?;
    Ok(conn.last_insert_rowid())
}

#[tauri::command]
pub fn update_client(state: State<AppState>, client: Client) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "UPDATE clients SET name = ?1, email = ?2, address = ?3, company = ?4, phone = ?5, tax_id = ?6, payment_terms = ?7, notes = ?8 WHERE id = ?9",
        params![client.name, client.email, client.address, client.company, client.phone, client.tax_id, client.payment_terms, client.notes, client.id],
    ).map_err(|e| e.to_string())?;
    Ok(())
}

#[tauri::command]
pub fn delete_client(state: State<AppState>, id: i64) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute("DELETE FROM clients WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
    Ok(())
}

// Project commands
#[tauri::command]
pub fn get_projects(state: State<AppState>) -> Result<Vec<Project>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let mut stmt = conn.prepare("SELECT id, client_id, name, hourly_rate, color, archived FROM projects ORDER BY name").map_err(|e| e.to_string())?;
    let projects = stmt.query_map([], |row| {
        Ok(Project {
            id: Some(row.get(0)?),
            client_id: row.get(1)?,
            name: row.get(2)?,
            hourly_rate: row.get(3)?,
            color: row.get(4)?,
            archived: row.get::<_, i32>(5)? != 0,
        })
    }).map_err(|e| e.to_string())?;
    projects.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())
}

#[tauri::command]
pub fn create_project(state: State<AppState>, project: Project) -> Result<i64, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT INTO projects (client_id, name, hourly_rate, color, archived) VALUES (?1, ?2, ?3, ?4, ?5)",
        params![project.client_id, project.name, project.hourly_rate, project.color, project.archived as i32],
    ).map_err(|e| e.to_string())?;
    Ok(conn.last_insert_rowid())
}

#[tauri::command]
pub fn update_project(state: State<AppState>, project: Project) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "UPDATE projects SET client_id = ?1, name = ?2, hourly_rate = ?3, color = ?4, archived = ?5 WHERE id = ?6",
        params![project.client_id, project.name, project.hourly_rate, project.color, project.archived as i32, project.id],
    ).map_err(|e| e.to_string())?;
    Ok(())
}

#[tauri::command]
pub fn delete_project(state: State<AppState>, id: i64) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute("DELETE FROM projects WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
    Ok(())
}

// Task commands
#[tauri::command]
pub fn get_tasks(state: State<AppState>, project_id: i64) -> Result<Vec<Task>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let mut stmt = conn.prepare("SELECT id, project_id, name FROM tasks WHERE project_id = ?1 ORDER BY name").map_err(|e| e.to_string())?;
    let tasks = stmt.query_map(params![project_id], |row| {
        Ok(Task {
            id: Some(row.get(0)?),
            project_id: row.get(1)?,
            name: row.get(2)?,
        })
    }).map_err(|e| e.to_string())?;
    tasks.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())
}

#[tauri::command]
pub fn create_task(state: State<AppState>, task: Task) -> Result<i64, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT INTO tasks (project_id, name) VALUES (?1, ?2)",
        params![task.project_id, task.name],
    ).map_err(|e| e.to_string())?;
    Ok(conn.last_insert_rowid())
}

#[tauri::command]
pub fn delete_task(state: State<AppState>, id: i64) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute("DELETE FROM tasks WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
    Ok(())
}

// Time entry commands
#[tauri::command]
pub fn get_time_entries(state: State<AppState>, start_date: Option<String>, end_date: Option<String>) -> Result<Vec<TimeEntry>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let query = match (start_date, end_date) {
        (Some(start), Some(end)) => {
            let mut stmt = conn.prepare(
                "SELECT id, project_id, task_id, description, start_time, end_time, duration
                 FROM time_entries
                 WHERE date(start_time) >= date(?1) AND date(start_time) <= date(?2)
                 ORDER BY start_time DESC"
            ).map_err(|e| e.to_string())?;
            let rows = stmt.query_map(params![start, end], |row| {
                Ok(TimeEntry {
                    id: Some(row.get(0)?),
                    project_id: row.get(1)?,
                    task_id: row.get(2)?,
                    description: row.get(3)?,
                    start_time: row.get(4)?,
                    end_time: row.get(5)?,
                    duration: row.get(6)?,
                })
            }).map_err(|e| e.to_string())?;
            rows.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?
        }
        _ => {
            let mut stmt = conn.prepare(
                "SELECT id, project_id, task_id, description, start_time, end_time, duration
                 FROM time_entries ORDER BY start_time DESC LIMIT 100"
            ).map_err(|e| e.to_string())?;
            let rows = stmt.query_map([], |row| {
                Ok(TimeEntry {
                    id: Some(row.get(0)?),
                    project_id: row.get(1)?,
                    task_id: row.get(2)?,
                    description: row.get(3)?,
                    start_time: row.get(4)?,
                    end_time: row.get(5)?,
                    duration: row.get(6)?,
                })
            }).map_err(|e| e.to_string())?;
            rows.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?
        }
    };
    Ok(query)
}

#[tauri::command]
pub fn create_time_entry(state: State<AppState>, entry: TimeEntry) -> Result<i64, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT INTO time_entries (project_id, task_id, description, start_time, end_time, duration)
         VALUES (?1, ?2, ?3, ?4, ?5, ?6)",
        params![entry.project_id, entry.task_id, entry.description, entry.start_time, entry.end_time, entry.duration],
    ).map_err(|e| e.to_string())?;
    Ok(conn.last_insert_rowid())
}

#[tauri::command]
pub fn update_time_entry(state: State<AppState>, entry: TimeEntry) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "UPDATE time_entries SET project_id = ?1, task_id = ?2, description = ?3,
         start_time = ?4, end_time = ?5, duration = ?6 WHERE id = ?7",
        params![entry.project_id, entry.task_id, entry.description, entry.start_time, entry.end_time, entry.duration, entry.id],
    ).map_err(|e| e.to_string())?;
    Ok(())
}

#[tauri::command]
pub fn delete_time_entry(state: State<AppState>, id: i64) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute("DELETE FROM time_entries WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
    Ok(())
}

// Reports
#[tauri::command]
pub fn get_reports(state: State<AppState>, start_date: String, end_date: String) -> Result<serde_json::Value, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;

    // Total hours
    let total: i64 = conn.query_row(
        "SELECT COALESCE(SUM(duration), 0) FROM time_entries
         WHERE date(start_time) >= date(?1) AND date(start_time) <= date(?2)",
        params![start_date, end_date],
        |row| row.get(0),
    ).map_err(|e| e.to_string())?;

    // By project - include project_id so frontend can look up name/color/rate
    let mut stmt = conn.prepare(
        "SELECT p.id, p.name, p.color, SUM(t.duration) as total_duration
         FROM time_entries t
         JOIN projects p ON t.project_id = p.id
         WHERE date(t.start_time) >= date(?1) AND date(t.start_time) <= date(?2)
         GROUP BY p.id
         ORDER BY total_duration DESC"
    ).map_err(|e| e.to_string())?;

    let by_project: Vec<serde_json::Value> = stmt.query_map(params![start_date, end_date], |row| {
        Ok(serde_json::json!({
            "project_id": row.get::<_, i64>(0)?,
            "name": row.get::<_, String>(1)?,
            "color": row.get::<_, String>(2)?,
            "total_seconds": row.get::<_, i64>(3)?
        }))
    }).map_err(|e| e.to_string())?
    .collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?;

    Ok(serde_json::json!({
        "totalSeconds": total,
        "byProject": by_project
    }))
}

// Invoice commands
#[tauri::command]
pub fn create_invoice(state: State<AppState>, invoice: Invoice) -> Result<i64, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT INTO invoices (client_id, invoice_number, date, due_date, subtotal, tax_rate, tax_amount, discount, total, notes, status)
         VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11)",
        params![invoice.client_id, invoice.invoice_number, invoice.date, invoice.due_date,
                invoice.subtotal, invoice.tax_rate, invoice.tax_amount, invoice.discount,
                invoice.total, invoice.notes, invoice.status],
    ).map_err(|e| e.to_string())?;
    Ok(conn.last_insert_rowid())
}

#[tauri::command]
pub fn get_invoices(state: State<AppState>) -> Result<Vec<Invoice>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let mut stmt = conn.prepare(
        "SELECT id, client_id, invoice_number, date, due_date, subtotal, tax_rate, tax_amount, discount, total, notes, status
         FROM invoices ORDER BY date DESC"
    ).map_err(|e| e.to_string())?;
    let invoices = stmt.query_map([], |row| {
        Ok(Invoice {
            id: Some(row.get(0)?),
            client_id: row.get(1)?,
            invoice_number: row.get(2)?,
            date: row.get(3)?,
            due_date: row.get(4)?,
            subtotal: row.get(5)?,
            tax_rate: row.get(6)?,
            tax_amount: row.get(7)?,
            discount: row.get(8)?,
            total: row.get(9)?,
            notes: row.get(10)?,
            status: row.get(11)?,
        })
    }).map_err(|e| e.to_string())?;
    invoices.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())
}

#[tauri::command]
pub fn update_invoice(state: State<AppState>, invoice: Invoice) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "UPDATE invoices SET client_id = ?1, invoice_number = ?2, date = ?3, due_date = ?4,
         subtotal = ?5, tax_rate = ?6, tax_amount = ?7, discount = ?8, total = ?9, notes = ?10, status = ?11
         WHERE id = ?12",
        params![invoice.client_id, invoice.invoice_number, invoice.date, invoice.due_date,
                invoice.subtotal, invoice.tax_rate, invoice.tax_amount, invoice.discount,
                invoice.total, invoice.notes, invoice.status, invoice.id],
    ).map_err(|e| e.to_string())?;
    Ok(())
}

#[tauri::command]
pub fn delete_invoice(state: State<AppState>, id: i64) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute("DELETE FROM invoices WHERE id = ?1", params![id]).map_err(|e| e.to_string())?;
    Ok(())
}

// Settings commands
#[tauri::command]
pub fn get_settings(state: State<AppState>) -> Result<std::collections::HashMap<String, String>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    let mut stmt = conn.prepare("SELECT key, value FROM settings").map_err(|e| e.to_string())?;
    let settings = stmt.query_map([], |row| {
        Ok((row.get::<_, String>(0)?, row.get::<_, String>(1)?))
    }).map_err(|e| e.to_string())?;

    let mut result = std::collections::HashMap::new();
    for setting in settings {
        let (key, value) = setting.map_err(|e| e.to_string())?;
        result.insert(key, value);
    }
    Ok(result)
}

#[tauri::command]
pub fn update_settings(state: State<AppState>, key: String, value: String) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute(
        "INSERT OR REPLACE INTO settings (key, value) VALUES (?1, ?2)",
        params![key, value],
    ).map_err(|e| e.to_string())?;
    Ok(())
}

// Export all data as JSON
#[tauri::command]
pub fn export_data(state: State<AppState>) -> Result<serde_json::Value, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;

    let clients = {
        let mut stmt = conn.prepare("SELECT id, name, email, address, company, phone, tax_id, payment_terms, notes FROM clients").map_err(|e| e.to_string())?;
        let rows: Vec<serde_json::Value> = stmt.query_map([], |row| {
            Ok(serde_json::json!({
                "id": row.get::<_, i64>(0)?,
                "name": row.get::<_, String>(1)?,
                "email": row.get::<_, Option<String>>(2)?,
                "address": row.get::<_, Option<String>>(3)?,
                "company": row.get::<_, Option<String>>(4)?,
                "phone": row.get::<_, Option<String>>(5)?,
                "tax_id": row.get::<_, Option<String>>(6)?,
                "payment_terms": row.get::<_, Option<String>>(7)?,
                "notes": row.get::<_, Option<String>>(8)?
            }))
        }).map_err(|e| e.to_string())?.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?;
        rows
    };

    let projects = {
        let mut stmt = conn.prepare("SELECT id, client_id, name, hourly_rate, color, archived FROM projects").map_err(|e| e.to_string())?;
        let rows: Vec<serde_json::Value> = stmt.query_map([], |row| {
            Ok(serde_json::json!({
                "id": row.get::<_, i64>(0)?,
                "client_id": row.get::<_, Option<i64>>(1)?,
                "name": row.get::<_, String>(2)?,
                "hourly_rate": row.get::<_, f64>(3)?,
                "color": row.get::<_, String>(4)?,
                "archived": row.get::<_, i32>(5)? != 0
            }))
        }).map_err(|e| e.to_string())?.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?;
        rows
    };

    let time_entries = {
        let mut stmt = conn.prepare("SELECT id, project_id, task_id, description, start_time, end_time, duration FROM time_entries").map_err(|e| e.to_string())?;
        let rows: Vec<serde_json::Value> = stmt.query_map([], |row| {
            Ok(serde_json::json!({
                "id": row.get::<_, i64>(0)?,
                "project_id": row.get::<_, i64>(1)?,
                "task_id": row.get::<_, Option<i64>>(2)?,
                "description": row.get::<_, Option<String>>(3)?,
                "start_time": row.get::<_, String>(4)?,
                "end_time": row.get::<_, Option<String>>(5)?,
                "duration": row.get::<_, i64>(6)?
            }))
        }).map_err(|e| e.to_string())?.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?;
        rows
    };

    let invoices = {
        let mut stmt = conn.prepare("SELECT id, client_id, invoice_number, date, due_date, subtotal, tax_rate, tax_amount, discount, total, notes, status FROM invoices").map_err(|e| e.to_string())?;
        let rows: Vec<serde_json::Value> = stmt.query_map([], |row| {
            Ok(serde_json::json!({
                "id": row.get::<_, i64>(0)?,
                "client_id": row.get::<_, i64>(1)?,
                "invoice_number": row.get::<_, String>(2)?,
                "date": row.get::<_, String>(3)?,
                "due_date": row.get::<_, Option<String>>(4)?,
                "subtotal": row.get::<_, f64>(5)?,
                "tax_rate": row.get::<_, f64>(6)?,
                "tax_amount": row.get::<_, f64>(7)?,
                "discount": row.get::<_, f64>(8)?,
                "total": row.get::<_, f64>(9)?,
                "notes": row.get::<_, Option<String>>(10)?,
                "status": row.get::<_, String>(11)?
            }))
        }).map_err(|e| e.to_string())?.collect::<Result<Vec<_>, _>>().map_err(|e| e.to_string())?;
        rows
    };

    Ok(serde_json::json!({
        "clients": clients,
        "projects": projects,
        "time_entries": time_entries,
        "invoices": invoices
    }))
}

// Clear all data
#[tauri::command]
pub fn clear_all_data(state: State<AppState>) -> Result<(), String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    conn.execute_batch(
        "DELETE FROM invoice_items;
         DELETE FROM invoices;
         DELETE FROM time_entries;
         DELETE FROM tasks;
         DELETE FROM projects;
         DELETE FROM clients;"
    ).map_err(|e| e.to_string())?;
    Ok(())
}