package service

import (
	"database/sql"
	"encoding/json/v2"
	"errors"
	"log/slog"
	"net/http"

	"code.chimeric.al/chimerical/odidere/internal/db"
)

func (svc *Service) listExecutions(w http.ResponseWriter, r *http.Request) {
	var (
		ctx = r.Context()
		log = ctx.Value(logKey).(*slog.Logger)
	)

	rows, err := svc.dbr.SelectPendingExecutions(ctx)
	if err != nil {
		log.ErrorContext(
			ctx, "failed to list pending executions",
			slog.Any("error", err),
		)
		http.Error(
			w,
			http.StatusText(http.StatusInternalServerError),
			http.StatusInternalServerError,
		)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	if err := json.MarshalWrite(w, rows); err != nil {
		log.ErrorContext(
			ctx, "failed to encode executions response",
			slog.Any("error", err),
		)
	}
}

func (svc *Service) updateExecution(w http.ResponseWriter, r *http.Request) {
	var (
		ctx = r.Context()
		log = ctx.Value(logKey).(*slog.Logger)
		req struct {
			Status db.ExecutionStatus `json:"status"`
		}
	)

	r.Body = http.MaxBytesReader(w, r.Body, 32<<20)
	if err := json.UnmarshalRead(r.Body, &req); err != nil {
		log.ErrorContext(
			ctx, "failed to decode request",
			slog.Any("error", err),
		)
		http.Error(w, "invalid request", http.StatusBadRequest)
		return
	}
	if req.Status != db.ExecutionStatusApproved &&
		req.Status != db.ExecutionStatusDenied {
		http.Error(w, "invalid status", http.StatusBadRequest)
		return
	}

	tx, err := svc.db.Writer.BeginTx(ctx, nil)
	if err != nil {
		log.ErrorContext(
			ctx, "failed to begin execution transaction",
			slog.Any("error", err),
		)
		http.Error(
			w,
			http.StatusText(http.StatusInternalServerError),
			http.StatusInternalServerError,
		)
		return
	}
	defer tx.Rollback()

	qtx := svc.dbw.WithTx(tx)
	execution, err := qtx.SelectExecutionId(ctx, r.PathValue("id"))
	if errors.Is(err, sql.ErrNoRows) {
		http.NotFound(w, r)
		return
	}
	if err != nil {
		log.ErrorContext(
			ctx, "failed to load execution",
			slog.Any("error", err),
		)
		http.Error(
			w,
			http.StatusText(http.StatusInternalServerError),
			http.StatusInternalServerError,
		)
		return
	}
	if execution.Status != db.ExecutionStatusPending {
		http.Error(w, "execution is not pending", http.StatusConflict)
		return
	}
	if err := qtx.UpdateExecutionStatus(ctx, db.UpdateExecutionStatusParams{
		Id:     execution.Id,
		Status: req.Status,
	}); err != nil {
		log.ErrorContext(
			ctx, "failed to update execution status",
			slog.Any("error", err),
		)
		http.Error(
			w,
			http.StatusText(http.StatusInternalServerError),
			http.StatusInternalServerError,
		)
		return
	}
	if err := tx.Commit(); err != nil {
		log.ErrorContext(
			ctx, "failed to commit execution transaction",
			slog.Any("error", err),
		)
		http.Error(
			w,
			http.StatusText(http.StatusInternalServerError),
			http.StatusInternalServerError,
		)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}