# Hearth Minimal Infrastructure
# Single EC2 + k3s for ~1 user
# Cost: ~$7.50/month

terraform {
  required_version = ">= 1.5.0"

  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.30"
    }
  }

  backend "s3" {
    bucket         = "hearth-terraform-state-181640953119"
    key            = "hearth-minimal/terraform.tfstate"
    region         = "us-east-1"
    dynamodb_table = "hearth-terraform-locks"
    encrypt        = true
    profile        = "hearth"
  }
}

provider "aws" {
  region  = var.aws_region
  profile = "hearth"

  default_tags {
    tags = {
      Project     = "hearth"
      Environment = "minimal"
      ManagedBy   = "terraform"
    }
  }
}

# -----------------------------------------------------------------------------
# Data Sources
# -----------------------------------------------------------------------------

data "aws_availability_zones" "available" {
  state = "available"
}

data "aws_caller_identity" "current" {}

# Amazon Linux 2023 ARM64 (for t4g instances)
data "aws_ami" "al2023" {
  most_recent = true
  owners      = ["amazon"]

  filter {
    name   = "name"
    values = ["al2023-ami-*-arm64"]
  }

  filter {
    name   = "virtualization-type"
    values = ["hvm"]
  }
}

# -----------------------------------------------------------------------------
# VPC - Minimal single public subnet
# -----------------------------------------------------------------------------

resource "aws_vpc" "main" {
  cidr_block           = "10.0.0.0/16"
  enable_dns_hostnames = true
  enable_dns_support   = true

  tags = {
    Name = "hearth-minimal"
  }
}

resource "aws_internet_gateway" "main" {
  vpc_id = aws_vpc.main.id

  tags = {
    Name = "hearth-minimal"
  }
}

resource "aws_subnet" "public" {
  vpc_id                  = aws_vpc.main.id
  cidr_block              = "10.0.1.0/24"
  availability_zone       = data.aws_availability_zones.available.names[0]
  map_public_ip_on_launch = true

  tags = {
    Name = "hearth-minimal-public"
  }
}

resource "aws_route_table" "public" {
  vpc_id = aws_vpc.main.id

  route {
    cidr_block = "0.0.0.0/0"
    gateway_id = aws_internet_gateway.main.id
  }

  tags = {
    Name = "hearth-minimal-public"
  }
}

resource "aws_route_table_association" "public" {
  subnet_id      = aws_subnet.public.id
  route_table_id = aws_route_table.public.id
}

# -----------------------------------------------------------------------------
# Security Group
# -----------------------------------------------------------------------------

resource "aws_security_group" "forgejo" {
  name        = "hearth-forgejo"
  description = "Security group for Forgejo server"
  vpc_id      = aws_vpc.main.id

  # SSH for Git (Forgejo)
  ingress {
    description = "Git SSH"
    from_port   = 22
    to_port     = 22
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  # HTTP (redirect to HTTPS)
  ingress {
    description = "HTTP"
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  # HTTPS
  ingress {
    description = "HTTPS"
    from_port   = 443
    to_port     = 443
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  # Admin SSH (restricted - update with your IP)
  ingress {
    description = "Admin SSH"
    from_port   = 2222
    to_port     = 2222
    protocol    = "tcp"
    cidr_blocks = var.admin_cidr_blocks
  }

  # Kubernetes API (for local kubectl, restricted)
  ingress {
    description = "Kubernetes API"
    from_port   = 6443
    to_port     = 6443
    protocol    = "tcp"
    cidr_blocks = var.admin_cidr_blocks
  }

  # DNS (UDP) - PowerDNS authoritative server
  ingress {
    description = "DNS UDP"
    from_port   = 53
    to_port     = 53
    protocol    = "udp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  # DNS (TCP) - PowerDNS authoritative server
  ingress {
    description = "DNS TCP"
    from_port   = 53
    to_port     = 53
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }

  # All outbound
  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }

  tags = {
    Name = "hearth-forgejo"
  }
}

# -----------------------------------------------------------------------------
# IAM Role for EC2 (S3 backup access)
# -----------------------------------------------------------------------------

resource "aws_iam_role" "forgejo" {
  name = "hearth-forgejo"

  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Action = "sts:AssumeRole"
        Effect = "Allow"
        Principal = {
          Service = "ec2.amazonaws.com"
        }
      }
    ]
  })
}

resource "aws_iam_role_policy" "forgejo_backup" {
  name = "forgejo-backup"
  role = aws_iam_role.forgejo.id

  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Effect = "Allow"
        Action = [
          "s3:PutObject",
          "s3:GetObject",
          "s3:ListBucket",
          "s3:DeleteObject"
        ]
        Resource = [
          aws_s3_bucket.backups.arn,
          "${aws_s3_bucket.backups.arn}/*"
        ]
      },
      {
        Effect = "Allow"
        Action = [
          "ec2:CreateSnapshot",
          "ec2:DescribeSnapshots",
          "ec2:DeleteSnapshot"
        ]
        Resource = "*"
      }
    ]
  })
}

resource "aws_iam_instance_profile" "forgejo" {
  name = "hearth-forgejo"
  role = aws_iam_role.forgejo.name
}

# -----------------------------------------------------------------------------
# S3 Bucket for Backups
# -----------------------------------------------------------------------------

resource "aws_s3_bucket" "backups" {
  bucket = "hearth-backups-${data.aws_caller_identity.current.account_id}"

  tags = {
    Name = "hearth-backups"
  }
}

resource "aws_s3_bucket_versioning" "backups" {
  bucket = aws_s3_bucket.backups.id

  versioning_configuration {
    status = "Enabled"
  }
}

resource "aws_s3_bucket_lifecycle_configuration" "backups" {
  bucket = aws_s3_bucket.backups.id

  rule {
    id     = "expire-old-backups"
    status = "Enabled"

    filter {
      prefix = ""
    }

    # Keep 60 days of backups
    expiration {
      days = 60
    }

    # Move to cheaper storage after 30 days (STANDARD_IA minimum)
    transition {
      days          = 30
      storage_class = "STANDARD_IA"
    }
  }
}

resource "aws_s3_bucket_server_side_encryption_configuration" "backups" {
  bucket = aws_s3_bucket.backups.id

  rule {
    apply_server_side_encryption_by_default {
      sse_algorithm = "AES256"
    }
  }
}

# -----------------------------------------------------------------------------
# EC2 Instance
# -----------------------------------------------------------------------------

resource "aws_instance" "forgejo" {
  ami                  = data.aws_ami.al2023.id
  instance_type        = var.instance_type
  subnet_id            = aws_subnet.public.id
  iam_instance_profile = aws_iam_instance_profile.forgejo.name

  vpc_security_group_ids = [aws_security_group.forgejo.id]

  # Use spot instance for cost savings
  instance_market_options {
    market_type = "spot"
    spot_options {
      max_price                      = var.spot_max_price
      spot_instance_type             = "persistent"
      instance_interruption_behavior = "stop"
    }
  }

  root_block_device {
    volume_size           = var.volume_size
    volume_type           = "gp3"
    iops                  = 3000
    throughput            = 125
    delete_on_termination = false  # Preserve data on instance termination
    encrypted             = true

    tags = {
      Name = "hearth-forgejo-root"
    }
  }

  user_data = base64encode(templatefile("${path.module}/user-data.sh", {
    domain            = var.domain
    letsencrypt_email = var.letsencrypt_email
    ssh_port          = var.admin_ssh_port
    s3_bucket         = aws_s3_bucket.backups.id
    ssh_public_key    = var.ssh_public_key
  }))

  tags = {
    Name = "hearth-forgejo"
  }

  lifecycle {
    ignore_changes = [ami, user_data]  # Don't replace on AMI or user-data changes
  }
}

# -----------------------------------------------------------------------------
# Elastic IP (stable DNS)
# -----------------------------------------------------------------------------

resource "aws_eip" "forgejo" {
  instance = aws_instance.forgejo.id
  domain   = "vpc"

  tags = {
    Name = "hearth-forgejo"
  }
}

# -----------------------------------------------------------------------------
# Outputs
# -----------------------------------------------------------------------------

output "instance_id" {
  description = "EC2 instance ID"
  value       = aws_instance.forgejo.id
}

output "public_ip" {
  description = "Elastic IP address"
  value       = aws_eip.forgejo.public_ip
}

output "ssh_command" {
  description = "SSH command for admin access"
  value       = "ssh -p ${var.admin_ssh_port} ec2-user@${aws_eip.forgejo.public_ip}"
}

output "forgejo_url" {
  description = "Forgejo web URL"
  value       = "https://${var.domain}"
}

output "git_clone_url" {
  description = "Git clone URL format"
  value       = "git@${var.domain}:ORG/REPO.git"
}

output "backup_bucket" {
  description = "S3 bucket for backups"
  value       = aws_s3_bucket.backups.id
}

output "dns_record" {
  description = "DNS A record to create"
  value       = "${var.domain} → ${aws_eip.forgejo.public_ip}"
}

output "powerdns_deploy_command" {
  description = "Command to deploy PowerDNS after instance is running"
  value       = <<-EOT
    # Copy and run deployment script:
    scp -P ${var.admin_ssh_port} scripts/deploy-powerdns.sh ec2-user@${aws_eip.forgejo.public_ip}:
    ssh -p ${var.admin_ssh_port} ec2-user@${aws_eip.forgejo.public_ip} 'sudo bash deploy-powerdns.sh ${aws_eip.forgejo.public_ip}'
  EOT
}

output "dns_glue_records" {
  description = "Glue records to configure at GoDaddy after PowerDNS is running"
  value       = <<-EOT
    For each managed domain, set nameservers and glue records:

    Nameservers:
      ns1.<domain>
      ns2.<domain>

    Glue Records:
      ns1 → ${aws_eip.forgejo.public_ip}
      ns2 → ${aws_eip.forgejo.public_ip}

    Domains: superviber.com, muffinlabs.ai, letemcook.com,
             appbasecamp.com, thanksforborrowing.com, alignment.coop
  EOT
}