-- CreateEnum
CREATE TYPE "SalaryItemType" AS ENUM ('earning', 'deduction');

-- CreateEnum
CREATE TYPE "PayslipStatus" AS ENUM ('draft', 'issued');

-- CreateTable
CREATE TABLE "salary_items" (
    "id" UUID NOT NULL,
    "name" TEXT NOT NULL,
    "item_type" "SalaryItemType" NOT NULL,
    "sort_order" INTEGER NOT NULL,
    "enabled" BOOLEAN NOT NULL DEFAULT true,
    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "created_by" UUID,
    "updated_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updated_by" UUID,

    CONSTRAINT "salary_items_pkey" PRIMARY KEY ("id")
);

-- CreateTable
CREATE TABLE "employee_salaries" (
    "id" UUID NOT NULL,
    "employee_id" UUID NOT NULL,
    "salary_item_id" UUID NOT NULL,
    "monthly_amount" DECIMAL(12,2) NOT NULL,
    "effective_date" DATE NOT NULL,
    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "created_by" UUID,
    "updated_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updated_by" UUID,

    CONSTRAINT "employee_salaries_pkey" PRIMARY KEY ("id")
);

-- CreateTable
CREATE TABLE "payslips" (
    "id" UUID NOT NULL,
    "employee_id" UUID NOT NULL,
    "pay_month" DATE NOT NULL,
    "status" "PayslipStatus" NOT NULL DEFAULT 'draft',
    "gross_amount" DECIMAL(12,2) NOT NULL DEFAULT 0,
    "deduction_amount" DECIMAL(12,2) NOT NULL DEFAULT 0,
    "net_amount" DECIMAL(12,2) NOT NULL DEFAULT 0,
    "issued_at" TIMESTAMP(3),
    "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "created_by" UUID,
    "updated_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
    "updated_by" UUID,

    CONSTRAINT "payslips_pkey" PRIMARY KEY ("id")
);

-- CreateTable
CREATE TABLE "payslip_items" (
    "id" UUID NOT NULL,
    "payslip_id" UUID NOT NULL,
    "salary_item_id" UUID NOT NULL,
    "amount" DECIMAL(12,2) NOT NULL DEFAULT 0,

    CONSTRAINT "payslip_items_pkey" PRIMARY KEY ("id")
);

-- CreateIndex
CREATE UNIQUE INDEX "salary_items_name_key" ON "salary_items"("name");

-- CreateIndex
CREATE INDEX "idx_salary_items_enabled_sort" ON "salary_items"("enabled", "sort_order");

-- CreateIndex
CREATE UNIQUE INDEX "employee_salaries_employee_item_effective_ux" ON "employee_salaries"("employee_id", "salary_item_id", "effective_date");

-- CreateIndex
CREATE INDEX "idx_employee_salaries_employee_effective" ON "employee_salaries"("employee_id", "effective_date");

-- CreateIndex
CREATE INDEX "idx_employee_salaries_salary_item" ON "employee_salaries"("salary_item_id");

-- CreateIndex
CREATE UNIQUE INDEX "payslips_employee_month_ux" ON "payslips"("employee_id", "pay_month");

-- CreateIndex
CREATE INDEX "idx_payslips_month_status" ON "payslips"("pay_month", "status");

-- CreateIndex
CREATE INDEX "idx_payslips_employee_month" ON "payslips"("employee_id", "pay_month");

-- CreateIndex
CREATE UNIQUE INDEX "payslip_items_payslip_salary_item_ux" ON "payslip_items"("payslip_id", "salary_item_id");

-- CreateIndex
CREATE INDEX "idx_payslip_items_salary_item" ON "payslip_items"("salary_item_id");

-- AddForeignKey
ALTER TABLE "employee_salaries" ADD CONSTRAINT "employee_salaries_employee_id_fkey" FOREIGN KEY ("employee_id") REFERENCES "employees"("id") ON DELETE CASCADE ON UPDATE CASCADE;

-- AddForeignKey
ALTER TABLE "employee_salaries" ADD CONSTRAINT "employee_salaries_salary_item_id_fkey" FOREIGN KEY ("salary_item_id") REFERENCES "salary_items"("id") ON DELETE RESTRICT ON UPDATE CASCADE;

-- AddForeignKey
ALTER TABLE "payslips" ADD CONSTRAINT "payslips_employee_id_fkey" FOREIGN KEY ("employee_id") REFERENCES "employees"("id") ON DELETE CASCADE ON UPDATE CASCADE;

-- AddForeignKey
ALTER TABLE "payslip_items" ADD CONSTRAINT "payslip_items_payslip_id_fkey" FOREIGN KEY ("payslip_id") REFERENCES "payslips"("id") ON DELETE CASCADE ON UPDATE CASCADE;

-- AddForeignKey
ALTER TABLE "payslip_items" ADD CONSTRAINT "payslip_items_salary_item_id_fkey" FOREIGN KEY ("salary_item_id") REFERENCES "salary_items"("id") ON DELETE RESTRICT ON UPDATE CASCADE;