using Fengling.AuthService.Data;
using Fengling.AuthService.Models;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using System.Security.Claims;
using System.Text.Json;

namespace Fengling.AuthService.Controllers;

[ApiController]
[Route("api/[controller]")]
[Authorize]
public class TenantsController : ControllerBase
{
    private readonly ApplicationDbContext _context;
    private readonly UserManager<ApplicationUser> _userManager;
    private readonly ILogger<TenantsController> _logger;

    public TenantsController(
        ApplicationDbContext context,
        UserManager<ApplicationUser> userManager,
        ILogger<TenantsController> logger)
    {
        _context = context;
        _userManager = userManager;
        _logger = logger;
    }

    [HttpGet]
    public async Task<ActionResult<object>> GetTenants(
        [FromQuery] int page = 1,
        [FromQuery] int pageSize = 10,
        [FromQuery] string? name = null,
        [FromQuery] string? tenantId = null,
        [FromQuery] string? status = null)
    {
        var query = _context.Tenants.AsQueryable();

        if (!string.IsNullOrEmpty(name))
        {
            query = query.Where(t => t.Name.Contains(name));
        }

        if (!string.IsNullOrEmpty(tenantId))
        {
            query = query.Where(t => t.TenantId.Contains(tenantId));
        }

        if (!string.IsNullOrEmpty(status))
        {
            query = query.Where(t => t.Status == status);
        }

        var totalCount = await query.CountAsync();
        var tenants = await query
            .OrderByDescending(t => t.CreatedAt)
            .Skip((page - 1) * pageSize)
            .Take(pageSize)
            .ToListAsync();

        var result = new List<object>();

        foreach (var tenant in tenants)
        {
            var userCount = await _context.Users.CountAsync(u => u.TenantId == tenant.Id && !u.IsDeleted);
            result.Add(new
            {
                id = tenant.Id,
                tenantId = tenant.TenantId,
                name = tenant.Name,
                contactName = tenant.ContactName,
                contactEmail = tenant.ContactEmail,
                contactPhone = tenant.ContactPhone,
                maxUsers = tenant.MaxUsers,
                userCount,
                status = tenant.Status,
                expiresAt = tenant.ExpiresAt,
                description = tenant.Description,
                createdAt = tenant.CreatedAt,
            });
        }

        return Ok(new
        {
            items = result,
            totalCount,
            page,
            pageSize
        });
    }

    [HttpGet("{id}")]
    public async Task<ActionResult<Tenant>> GetTenant(long id)
    {
        var tenant = await _context.Tenants.FindAsync(id);
        if (tenant == null)
        {
            return NotFound();
        }

        return Ok(new
        {
            id = tenant.Id,
            tenantId = tenant.TenantId,
            name = tenant.Name,
            contactName = tenant.ContactName,
            contactEmail = tenant.ContactEmail,
            contactPhone = tenant.ContactPhone,
            maxUsers = tenant.MaxUsers,
            status = tenant.Status,
            expiresAt = tenant.ExpiresAt,
            description = tenant.Description,
            createdAt = tenant.CreatedAt,
            updatedAt = tenant.UpdatedAt,
        });
    }

    [HttpGet("{tenantId}/users")]
    public async Task<ActionResult<List<object>>> GetTenantUsers(string tenantId)
    {
        var tenant = await _context.Tenants.FirstOrDefaultAsync(t => t.TenantId == tenantId);
        if (tenant == null)
        {
            return NotFound();
        }

        var users = await _context.Users
            .Where(u => u.TenantId == tenant.Id && !u.IsDeleted)
            .ToListAsync();

        var result = users.Select(async u => new
        {
            id = u.Id,
            userName = u.UserName,
            email = u.Email,
            realName = u.RealName,
            tenantId = u.TenantId,
            roles = await _userManager.GetRolesAsync(u),
            isActive = !u.LockoutEnabled || u.LockoutEnd == null || u.LockoutEnd < DateTimeOffset.UtcNow,
            createdAt = u.CreatedTime,
        });

        return Ok(await Task.WhenAll(result));
    }

    [HttpGet("{tenantId}/roles")]
    public async Task<ActionResult<List<object>>> GetTenantRoles(string tenantId)
    {
        var tenant = await _context.Tenants.FirstOrDefaultAsync(t => t.TenantId == tenantId);
        if (tenant == null)
        {
            return NotFound();
        }

        var roles = await _context.Roles
            .Where(r => r.TenantId == tenant.Id)
            .ToListAsync();

        var result = roles.Select(r => new
        {
            id = r.Id,
            name = r.Name,
            displayName = r.DisplayName,
        });

        return Ok(result);
    }

    [HttpGet("{tenantId}/settings")]
    public async Task<ActionResult<TenantSettings>> GetTenantSettings(string tenantId)
    {
        var tenant = await _context.Tenants.FirstOrDefaultAsync(t => t.TenantId == tenantId);
        if (tenant == null)
        {
            return NotFound();
        }

        var settings = new TenantSettings
        {
            AllowRegistration = false,
            AllowedEmailDomains = "",
            DefaultRoleId = null,
            PasswordPolicy = new List<string> { "requireNumber", "requireLowercase" },
            MinPasswordLength = 8,
            SessionTimeout = 120,
        };

        return Ok(settings);
    }

    [HttpPut("{tenantId}/settings")]
    public async Task<IActionResult> UpdateTenantSettings(string tenantId, TenantSettings settings)
    {
        var tenant = await _context.Tenants.FirstOrDefaultAsync(t => t.TenantId == tenantId);
        if (tenant == null)
        {
            return NotFound();
        }

        await CreateAuditLog("tenant", "update", "TenantSettings", tenant.Id, tenant.TenantId, null, JsonSerializer.Serialize(settings));

        return NoContent();
    }

    [HttpPost]
    public async Task<ActionResult<Tenant>> CreateTenant(CreateTenantDto dto)
    {
        var tenant = new Tenant
        {
            TenantId = dto.TenantId,
            Name = dto.Name,
            ContactName = dto.ContactName,
            ContactEmail = dto.ContactEmail,
            ContactPhone = dto.ContactPhone,
            MaxUsers = dto.MaxUsers,
            Description = dto.Description,
            Status = dto.Status,
            ExpiresAt = dto.ExpiresAt,
            CreatedAt = DateTime.UtcNow,
        };

        _context.Tenants.Add(tenant);
        await _context.SaveChangesAsync();

        await CreateAuditLog("tenant", "create", "Tenant", tenant.Id, tenant.TenantId, null, JsonSerializer.Serialize(dto));

        return CreatedAtAction(nameof(GetTenant), new { id = tenant.Id }, tenant);
    }

    [HttpPut("{id}")]
    public async Task<IActionResult> UpdateTenant(long id, UpdateTenantDto dto)
    {
        var tenant = await _context.Tenants.FindAsync(id);
        if (tenant == null)
        {
            return NotFound();
        }

        var oldValue = JsonSerializer.Serialize(tenant);

        tenant.Name = dto.Name;
        tenant.ContactName = dto.ContactName;
        tenant.ContactEmail = dto.ContactEmail;
        tenant.ContactPhone = dto.ContactPhone;
        tenant.MaxUsers = dto.MaxUsers;
        tenant.Description = dto.Description;
        tenant.Status = dto.Status;
        tenant.ExpiresAt = dto.ExpiresAt;
        tenant.UpdatedAt = DateTime.UtcNow;

        await _context.SaveChangesAsync();

        await CreateAuditLog("tenant", "update", "Tenant", tenant.Id, tenant.TenantId, oldValue, JsonSerializer.Serialize(tenant));

        return NoContent();
    }

    [HttpDelete("{id}")]
    public async Task<IActionResult> DeleteTenant(long id)
    {
        var tenant = await _context.Tenants.FindAsync(id);
        if (tenant == null)
        {
            return NotFound();
        }

        var oldValue = JsonSerializer.Serialize(tenant);

        var users = await _context.Users.Where(u => u.TenantId == tenant.Id).ToListAsync();
        foreach (var user in users)
        {
            user.IsDeleted = true;
            user.UpdatedTime = DateTime.UtcNow;
        }

        tenant.IsDeleted = true;
        await _context.SaveChangesAsync();

        await CreateAuditLog("tenant", "delete", "Tenant", tenant.Id, tenant.TenantId, oldValue);

        return NoContent();
    }

    private async Task CreateAuditLog(string operation, string action, string targetType, long? targetId, string? targetName, string? oldValue = null, string? newValue = null)
    {
        var userName = User.FindFirstValue(ClaimTypes.NameIdentifier) ?? User.Identity?.Name ?? "system";
        var tenantId = User.FindFirstValue("TenantId");

        var log = new AuditLog
        {
            Operator = userName,
            TenantId = tenantId,
            Operation = operation,
            Action = action,
            TargetType = targetType,
            TargetId = targetId,
            TargetName = targetName,
            IpAddress = HttpContext.Connection.RemoteIpAddress?.ToString() ?? "unknown",
            Status = "success",
            OldValue = oldValue,
            NewValue = newValue,
        };

        _context.AuditLogs.Add(log);
        await _context.SaveChangesAsync();
    }
}

public class CreateTenantDto
{
    public string TenantId { get; set; } = string.Empty;
    public string Name { get; set; } = string.Empty;
    public string ContactName { get; set; } = string.Empty;
    public string ContactEmail { get; set; } = string.Empty;
    public string? ContactPhone { get; set; }
    public int? MaxUsers { get; set; }
    public string? Description { get; set; }
    public string Status { get; set; } = "active";
    public DateTime? ExpiresAt { get; set; }
}

public class UpdateTenantDto
{
    public string Name { get; set; } = string.Empty;
    public string ContactName { get; set; } = string.Empty;
    public string ContactEmail { get; set; } = string.Empty;
    public string? ContactPhone { get; set; }
    public int? MaxUsers { get; set; }
    public string? Description { get; set; }
    public string Status { get; set; } = "active";
    public DateTime? ExpiresAt { get; set; }
}

public class TenantSettings
{
    public bool AllowRegistration { get; set; }
    public string AllowedEmailDomains { get; set; } = string.Empty;
    public long? DefaultRoleId { get; set; }
    public List<string> PasswordPolicy { get; set; } = new();
    public int MinPasswordLength { get; set; } = 8;
    public int SessionTimeout { get; set; } = 120;
}